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1-1-2008

Product Formulation And Consumer Acceptability Of Processed Cheese Made With Different Types Of Cocoas And Chocolates & Product Formulation And Quantitative Descriptive Analysis Of Aged Cheddar Cheese With Different Types Of Chocolate Inclusions

Vishal Kumar Royyala

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This Graduate Thesis - Open Access is brought to you for free and open access by the Theses and Dissertations at Scholars Junction. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of Scholars Junction. For more information, please contact [email protected]. PRODUCT FORMULATION AND CONSUMER ACCEPTABILITY OF PROCESSED

CHEESE MADE WITH DIFFERENT TYPES OF COCOAS AND CHOCOLATES

&

PRODUCT FORMULATION AND QUANTITATIVE DESCRIPTIVE

ANALYSIS OF AGED CHEDDAR CHEESE

WITH DIFFERENT TYPES OF

CHOCOLATE INCLUSIONS

By

Vishal Kumar Royyala

A Thesis Submitted to the Faculty of Mississippi State University in Partial Fulfillment of the Requirements for the Degree of Master of Science in Food Science and Technology in the Department of Food Science, Nutrition and Health Promotion

Mississippi State, Mississippi

December 2008 Copyright by

Vishal Kumar Royyala

2008 PRODUCT FORMULATION AND CONSUMER ACCEPTABILITY OF PROCESSED

CHEESE MADE WITH DIFFERENT TYPES OF COCOAS AND CHOCOLATES

&

PRODUCT FORMULATION AND QUANTITATIVE DESCRIPTIVE

ANALYSIS OF AGED CHEDDAR CHEESE

WITH DIFFERENT TYPES OF

CHOCOLATE INCLUSIONS

By

Vishal Kumar Royyala

Approved:

______Patti C. Coggins J. Byron Williams Assistant Research Professor Assistant Professor Food Science, Nutrition and Health Promotion Food Science, Nutrition and Health Promotion (Director of Thesis) (Committee Member) (Committee Member)

______James M. Martin Juan L. Silva Assistant Professor Graduate Coordinator, and Professor Food Science, Nutrition and Health Promotion Food Science, Nutrition and Health Promotion (Committee Member)

______Melissa Mixon Interim Vice President, Division of Agriculture, Forestry and Veterinary Medicine, Director, Mississippi Agriculture and Forestry Experiment Station Dean of College of Agriculture and Life Sciences Name: Vishal Kumar Royyala

Date of Degree: December 5, 2008

Institution: Mississippi State University

Major Field: Food Science

Major Professor: Dr. Patti C. Coggins

Title of Study: PRODUCT FORMULATION AND CONSUMER ACCEPTABILITY OF PROCESSED CHEESE MADE WITH DIFFERENT TYPES OF COCOAS AND CHOCOLATES & PRODUCT FORMULATION AND QUANTITATIVE DESCRIPTIVE ANALYSIS OF AGED CHEDDAR CHEESE WITH DIFFERENT TYPES OF CHOCOLATE INCLUSIONS

Pages in Study: 158

Candidate for Degree of Master of Science

The objectives of this research were to compare different types of cocoa and chocolates in the formulation of processed chocolate cheese and aged Cheddar cheese, and to evaluate sensory, physical, chemical and quality parameters of each. Four different varieties of chocolates were utilized along with other ingredients to prepare processed chocolate cheeses and were tested for consumer acceptability for their basic and critical attributes. Chocolate chips of four different types and proportions were incorporated into

Cheddar cheese curd, ripened for 105 days, and a trained panel evaluated the sensory parameters. Results indicated that processed chocolate cheese made with Bordeaux chocolate was preferred the most by consumers, followed by those prepared with

Ghirardelli, German and Dutch chocolates, respectively. This research provides a platform to pioneer the study of the sensory profiles of the processed chocolate cheeses. Development of a lexiconal study for the Cheddar cheeses with chocolate chips is also necessitated.

Keywords: Cheddar cheese, chocolate, processed chocolate cheese, aged Cheddar cheese, chocolate chip inclusions. DEDICATION

I dedicate this manuscript to my beloved father Ashok Royyala, for his constant endeavor to motivate me to pursue higher education and his sacrifices to bring meaning to my life. I would also like to dedicate this work to my loving mother Yashoda Royyala for her understanding and tremendous belief in me and for relentlessly persuading me and telling me “who I am”.

The dedication is also to Ashley N. Pollard, who has been instrumental in shaping my individuality during my Master’s degree, enabling me to be a responsible individual through her remarkable help which drove in me a constant burning desire “to achieve more” and to have an appreciation for my work. I would also like to dedicate this work to my friends Mr. Vinay Thotakura, Mr. Somayajulu Lanka, Mr. Nanda Joginapalli, Mr.

Dileep Godavarthi, and Mr. Chinni Yalamanchili, to whom I will always be indebted for their help to shower concern upon me. Without Dr. Douglas Marshall’s good advice and his amazing ability to transcend to touch my problems I faced as a student, this work could not have been possible and he deserves every bit of my dedication for being a reason for all of my work. The amount of concern that Dr. Patti C. Coggins showed during the tough times that I have been through to finish my thesis and her kind heartedness towards the students makes me feel as if I owe this dedication completely to her.

ii ACKNOWLEDGEMENTS

The author would like to convey his genuine appreciation to various people who assisted and influenced me to successfully accomplish the writing of my Masters’ thesis.

First, I must thank Mr. Joseph Andol whose moral support fueled my enthusiasm to successfully finish my writing and had a significant contribution on my work. His contribution is reflected in the following document. Sir, you motivated me, helped me with the statistics, channeled my energy in the right path, and most notably, you taught me the beauty of organizing my thoughts to be manifested into actions.

I have a higher regard for all of my enthusiastic panelists for participating in the descriptive study; your commitment to go through such rigorous sessions that spanned during the 45 day period was really appreciated. All of my panelists, namely, Dr. Patti C.

Coggins, Dr. Byron Williams, Ms. Julie Wilson, Ms. April Gandy, Ms. Ashley Pollard and Mr. Jovy Duran, put in a great deal of energy to bring life to each and every panel.

Dr. Williams, your suggestions were invaluable and were very thought provoking.

Thanks to April and Ashley, who constantly kept me informed with what was happening during the panels and updated my knowledge on the descriptive sensory language from time to time. I want to especially thank Julie Wilson, Dr. Coggins, and Dr. Williams for leading the panels and taking the initiative whenever possible to run the panels smoothly in an educative way.

iii I sincerely thank Ms. Julie Wilson for enabling me to smoothly proceed through the entire process of the experimental part of my research. Your authority over the subject matter is quite undeniable, and your constructive criticism will definitely help me in the future to be a better researcher and to be an asset to any organization that I might work for.

I owe an exceptional degree of gratitude to my long term friend Samala Aditya

(Sammy) for constantly supporting and morally uplifting me each and every moment.

Sammy, with your funny nature, you charged up the whole environment around you and you kept me on my toes all the time. I also thank our duo friends Jovy Duran and April

Gandy for being very helpful and understanding. Jovy Duran, with his amazing ability to go beyond what is seen and to comprehend the observed, always helped me to notice the much neglected matters. In addition, April Gandy with her awesome communication skills and with her untiring listening skills, provided me with a great deal of common sense to organize my research work. A special mention and a thank you note for Husniye

Imamoglu for being the forerunner in her research work, for being able to help me out with the statistical data and for spending countless hours encouraging me to finish the work. I am very grateful for the moral support that I had received from Kai-Ts’ung Yang.

The significant help that I had received from my other lab mates Rosa Hwang, Ye Tian,

Shweta Kumari, Robert Anderson, Mahitha Paka and Nick Buskens is also very unforgettable and many thanks to each one of you.

I also feel that without Dr. Wes Schilling’s and Dr. Dennis Rowe’s help this thesis would not have taken its present shape, and I am greatly obliged to both of their

iv generosity for extending their help with statistical methods to analyze the experimental data of my work. I sincerely thank Dr. Igathinathane Cannayen and Dr. Lester Pordesimo for all their help to let me pass through the tough situations. My gratitude to Vamshidhar

Battula whose patience articulated the significance of the statistical concepts reflected in this work. My deep gratefulness to Alessandra Pham for her willingness to help me, and I thank Vimal Kamadia, Sovann Kin, and Vijay for their support. I also thank Oleksandr

Tokarskyy for his noticeable help with the microbiological analysis of the samples.

This exciting experience could not have been possible without the help of

Mississippi State University’s Edward W. Custer dairy plant personnel. First of all, I sincerely appreciate the amount of help that I have received from Mark Chapman. Thank you, Mr. David Hall, for letting me utilize the dairy plant facilities. I would like to thank

Tony Gallman, Thomas Tuck and Zane Popwell, each one of them lending a hand whenever I needed help. I want to express a kind and warm heartfelt gratitude towards

Mr. Jimmy Fox for allowing me to use the Ammerman-Hernsberger pilot plant facilities and for all of his help.

I also want to thank Ms. Donna Bland and the Department of Food Science,

Nutrition and Health Promotion for the necessary help with the paper work and for enabling me to better understand how things work. My thanks are also due to Dr. Mike

Martin for being on my committee.

Last, but not the least, I would also like to express my gratitude to Karl Bell,

Patrick Young, Sarah Duffy, Michael Robert, Thomas, Bobby and all IMC staff, Damen

Peterson, Dr. Bradley Brazzeal and thesis and dissertation services; both in the MSU

v Library. I also thank the writing center in the English department for the corrections they did. I am also grateful for the noteworthy assistance that I have received from Mukesh and Sanjay (Dada). I am thoroughly appreciative of the moral support that I have received from my friends, Vijay (Mama), Babi, Parapudi, Abhi, Sega, Sudhir Koduri,

Goli, Phani, Velagapalli, Bolla, Kamireddy, Sandeep Govind, V.K. Garu, Bablu, Hyma,

Toparam, Anji, Sreedhar, Gopal, Gangadhar, Amar Varma, Amar and Srinivas

Damodara. I also enjoyed the constant support provided by my sisters Sravani and

Shailaja. My best friends Damu and Seenu always have a profound influence over my life and the drive for the quest of knowledge. Thank you to each one of you!!

vi TABLE OF CONTENTS

Page

DEDICATION...... ii

ACKNOWLEDGEMENTS...... iii

LIST OF TABLES...... x

LIST OF FIGURES ...... xii

CHAPTER

I. INTRODUCTION ...... 1

II. REVIEW OF LITERATURE ...... 3 Cheddar Cheese ...... 3 History...... 3 Production & Marketing ...... 4 Fat, Moisture and Salt Contents of Cheddar Cheese and Interactions ..... 5 Flavor of Cheddar Cheese...... 10 Texture of Cheddar Cheese...... 11 Descriptive Sensory Language for the Evaluation of Cheddar Cheese ... 12 Aged Cheddar Cheese...... 18 Processed Cheese ...... 19 First Generation………………………...... 21 Second Generation ...... 21 Third Generation ...... 21 Innovations or New Trends in Processed Cheese Technologies ...... 24 Emulsifiers ...... 25 Chocolate ...... 26 Processed Chocolate Cheese ...... 29

III. PRODUCT FORMULATION AND CONSUMER ACCEPTABILITY OF PROCESSED CHEESE MADE WITH DIFFERENT TYPES OF COCOAS AND CHOCOLATES… ...... 31

vii Abstract...... 31 Introduction...... 31 Materials and Methods...... 33 Equipment and Materials ...... 33 Formulations and Laboratory Processing of Chocolate Cheese ...... 33 Consumer Acceptability using Sensory Testing ...... 37 Statistical Analysis ...... 37 Cluster Analysis ...... 38 Results and Discussion ...... 40 Consumer Acceptability...... 40 Cluster Analysis ...... 42 Conclusion ...... 44

IV. PRODUCT FORMULATION AND QUANTITATIVE DESCRIPTIVE ANALYSIS OF AGED CHEDDAR CHEESE WITH DIFFERENT TYPES OF CHOCOLATE INCLUSIONS ...... 46

Abstract...... 46 Introduction...... 46 Materials and Methods...... 49 Formulations ...... 49 Process Description ...... 49 Microbial Analysis of Cheddar Cheeses with Chocolate Chips ...... 50 Sampling ...... 51 Apparatus Needed ...... 51 Procedure ...... 51 Panel Preparation (Training) ...... 52 Panel...... 53 Panelists ...... 53 Panelists’ Training ...... 54 Testing Area ...... 54 Sample Preparation ...... 54 Selection of the Descriptive Terms and Preparation of the Corresponding Standards ...... 56 Statistical Analysis ...... 59 Principal Component Analysis (PCA) ...... 60 Results and Discussion ...... 61 Microbial Analysis ...... 61 Quantitative Descriptive Analysis ...... 61 Descriptive Analysis: Appearance ...... 61 Descriptive Analysis: Basic Taste(s) ...... 63 Descriptive Analysis: Flavor ...... 65 Descriptive Analysis: Texture ...... 68 Interpretation of Interaction Plots between Panelist & Treatment ..... 69

viii Significance of Panelist * Treatment Interactions ...... 73 Principal Component Analysis ...... 73 Correlation Matrix ...... 77 Conclusion ...... 80

V. SUMMARY, IMPLICATIONS AND CONCLUSIONS...... 81

REFERENCES ...... 82

APPENDIX A. INTERACTION PLOTS AND COMPARISON AMONG DIFFERENT TYPES OF CHEDDAR CHEESES WITH CHOCOLATE CHIPS FOR THEIR DESCRIPTIVELY ANALYZED ATTRIBUTES ...... 93

B. SCORESHEETS FOR THE CONSUMER PANELS, INGREDIENT LISTS, AND CONSENT FORMS ...... 137

Processed Chocolate Cheese Ingredients ...... 142 Basic Taste Solutions used for the descriptive panels ...... 144 Products used for the descriptive panel ...... 145 Different Danish Blue cheese dilutions used for the descriptive panels...... 146 Replication 1, Replication 2, Replication 3 ...... 146 Replication 1 formulations for the Cheddar cheeses with chocolate chips ... 147 Replication 2 formulations for the Cheddar cheeses with chocolate chips ... 148 Replication 3 formulations for the Cheddar cheeses with chocolate chips ... 149 Processed Chocolate Cheese Codes for Consumer Panels ...... 150

C. SCORESHEET FOR THE DESCRIPTIVE PANEL ...... 153

ix LIST OF TABLES

TABLE Page

3.1 Final formulation of processed chocolate cheese using German chocolate .. 35

3.2 Final formulation of processed chocolate cheese using Dutch cocoa ...... 36

3.3 Final formulation of processed chocolate cheese using Ghirardelli chocolate ...... 36

3.4 Final formulation of processed chocolate cheese using Bordeaux chocolate ...... 36

3.5 Overall intensity means for all the processed chocolate cheeses for different parameters evaluated using the consumer panels for acceptability ...... 41

3.6 Centroid scores on a 9-point hedonic scale for clusters of consumer segments with varying preferences for processed chocolate cheeses ...... 42

4.1 Appearance attributes for Cheddar cheeses with chocolate chips, as determined by panelists ...... 57

4.2 Basic taste attributes for Cheddar cheeses with chocolate chips, as determined by panelists ...... 57

4.3 Flavor attributes for Cheddar cheeses with chocolate chips, as determined by panelists ...... 58

4.4 Texture attributes (hand evaluated) for Cheddar cheeses with chocolate chips, as determined by panelists ...... 59

x 4.5 Descriptive appearance attribute intensity means for the Cheddar cheeses with chocolate chips and control, as determined by a trained panel (n=6) ...... 63

4.6 Descriptive basic taste attribute intensity means for the Cheddar cheeses with chocolate chips and control, as determined by a trained panel (n=6) ...... 65

4.7 Descriptive flavor attribute intensity means for the Cheddar cheeses with chocolate chips and control, as determined by a trained panel (n=6) ...... 68

4.8 Descriptive texture attribute intensity means for the Cheddar cheeses with chocolate chips and control, as determined by a trained panel (n=6) ..... 69

4.9 Eigen component factors that account for 89% of the total variation in principal component analysis of different attributes of different treatments ...... 75

4.10 Correlation matrix between significantly correlated (P<0.05) descriptive attributes (at correlation r=0.754) used to profile Cheddar cheeses with chocolate chips ...... 79

4.11 Basic taste solution-sweet ...... 144

4.12 Basic taste solution-bitter...... 144

4.13 Basic taste solution-sour ...... 144

4.14 Basic taste solution-salty...... 144

4.15 Basic taste solution-umami ...... 144

4.16 Products used for the descriptive panel ...... 145

4.17 Different Danish blue cheese dilutions used for the descriptive panels ...... 146

4.18 Replication 1 formulations for the Cheddar cheeses with chocolate chips. .. 147

4.19 Replication 2 formulations for the Cheddar cheeses with chocolate chips. .. 148

4.20 Replication 3 formulations for the Cheddar cheeses with chocolate chips. .. 149

xi LIST OF FIGURES

FIGURE Page

3.1 Graphical representation of ranked overall preferences as given by the consumers for consumer acceptability of processed chocolate cheeses made with different types of cocoas and chocolates ...... 41

3.2 Dendrogram for 148 consumers surveyed, truncated at the level of 21 dissimilarity, indicating the six clusters of consumer segmentations for processed chocolate cheese preferences for overall liking...... 43

4.1 Principal component biplot of descriptive analysis for all the significant (P<0.05) attributes of different varieties of Cheddar cheeses with chocolate chips ...... 76

4.2 Interaction among the panelists for “distribution of chocolate and cheese” attribute among different varieties of Cheddar cheeses with chocolate chips ...... 94

4.3 Interaction among the panelists for “evenness of color (cheese only)” attribute among different varieties of Cheddar cheeses with chocolate chips ...... 95

4.4 Interaction among the panelists for basic taste “bitter” among different varieties of Cheddar cheeses with chocolate chips ...... 96

4.5 Interaction among the panelists for basic taste “salty” among different varieties of Cheddar cheeses with chocolate chips ...... 97

4.6 Interaction among the panelists for basic taste “sweet” among different varieties of Cheddar cheeses with chocolate chips ...... 98

4.7 Interaction among the panelists for basic taste “sour” among different varieties of Cheddar cheeses with chocolate chips ...... 99

xii 4.8 Interaction among the panelists for basic taste “umami” among different varieties of Cheddar cheeses with chocolate chips ...... 100

4.9 Interaction among the panelists for “cheese flavor” attribute among different varieties of Cheddar cheeses with chocolate chips ...... 101

4.10 Interaction among the panelists for “cooked flavor” attribute among different varieties of Cheddar cheeses with chocolate chips ...... 102

4.11 Interaction among the panelists for “sulfur flavor” attribute among different varieties of Cheddar cheeses with chocolate chips ...... 103

4.12 Interaction among the panelists for “nutty flavor” attribute among different varieties of Cheddar cheeses with chocolate chips ...... 104

4.13 Interaction among the panelists for “chocolate flavor” attribute among different varieties of Cheddar cheeses with chocolate chips ...... 105

4.14 Interaction among the panelists for texture attribute “firmness” among different varieties of Cheddar cheeses with chocolate chips ...... 106

4.15 Interaction among the panelists for texture attribute “crumbliness” among different varieties of Cheddar cheeses with chocolate chips ...... 107

4.16 Interaction among the panelists for texture attribute “springiness” among different varieties of Cheddar cheeses with chocolate chips ...... 108

4.17 Graphical representation of descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet and bittersweet with chocolate chips ...... 109

4.18 Spider plot for descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet and bittersweet with chocolate chips ...... 109

4.19 Graphical representation of descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet and bittersweet with chocolate chips ...... 110

4.20 Spider plot for descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet and bittersweet with chocolate chips ...... 110

xiii 4.21 Graphical representation of descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet and bittersweet with chocolate chips ...... 111

4.22 Spider plot for descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet and bittersweet with chocolate chips ...... 111

4.23 Graphical representation of descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet and bittersweet chocolate chips .... 112

4.24 Spider plot for descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet and bittersweet with chocolate chips ...... 112

4.25 Graphical representation of descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 20% chocolate chips ...... 113

4.26 Spider plot for descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 20% chocolate chips ...... 113

4.27 Graphical representation of descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 20% chocolate chips ...... 114

4.28 Spider plot for descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 20% chocolate chips ...... 114

4.29 Graphical representation of descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 20% chocolate chips ...... 115

4.30 Spider plot for descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 20% chocolate chips ...... 115

4.31 Graphical representation of descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 20% chocolate chips ...... 116

4.32 Spider plot for descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 20% chocolate chips ..... 116

xiv 4.33 Graphical representation of descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 15% chocolate chips ...... 117

4.34 Spider plot for descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 15% chocolate chips ...... 117

4.35 Graphical representation of descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 15% chocolate chips ...... 118

4.36 Spider plot for descriptive basic taste attributes intensity mean of Cheddar cheeses with semi-sweet 20% and bittersweet 15% chocolate chips ...... 118

4.37 Graphical representation of descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 15% chocolate chips ...... 119

4.38 Spider plot for descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 15% chocolate chips ...... 119

4.39 Graphical representation of descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 15% chocolate chips ...... 120

4.40 Spider plot for descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 15% chocolate chips ...... 120

4.41 Graphical representation of descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips ...... 121

4.42 Spider plot for descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips ...... 121

4.43 Graphical representation of descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips ...... 122

xv 4.44 Spider plot for descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips ...... 122

4.45 Graphical representation of descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips ...... 123

4.46 Spider plot for descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips ...... 123

4.47 Graphical representation of descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips ...... 124

4.48 Spider plot for descriptive texture attributes intensity mean of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips ...... 124

4.49 Graphical representation of descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips ...... 125

4.50 Spider plot for descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips ...... 125

4.51 Graphical representation of descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips ...... 126

4.52 Spider plot for descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips ...... 126

4.53 Graphical representation of descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips ...... 127

4.54 Spider plot for descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips ………………………… ...... 127

xvi 4.55 Graphical representation of descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips ...... 128

4.56 Spider plot for descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips ...... 128

4.57 Graphical representation of descriptive appearance attributes intensity means of cheddar cheeses with bittersweet 15% and bittersweet 20% chocolate chips ...... 129

4.58 Spider plot for descriptive appearance attributes intensity means of cheddar cheeses with bittersweet 15% and bittersweet 20% chocolate chips ...... 129

4.59 Graphical representation of descriptive basic taste attributes intensity means of Cheddar cheeses with bittersweet 15% and bittersweet 20% chocolate chips ...... 130

4.60 Spider plot for descriptive basic taste attributes intensity means of cheddar cheeses with bittersweet 15% and bittersweet 20% chocolate chips ...... 130

4.61 Graphical representation of descriptive flavor attributes intensity means of Cheddar cheeses with bittersweet 15% and bittersweet 20% chocolate chips ...... 131

4.62 Spider plot for descriptive flavor attributes intensity means of Cheddar cheeses with bittersweet 15% and bittersweet 20% chocolate chips ...... 131

4.63 Graphical representation of descriptive texture attributes intensity means of Cheddar cheeses with bittersweet 15% and bittersweet 20% chocolate chips ...... 132

4.64 Spider plot for descriptive texture attributes intensity means of Cheddar cheeses with bittersweet 15% and bittersweet 20% chocolate chips ...... 132

4.65 Graphical representation of descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 20% and semi-sweet 15% chocolate chips ...... 133

xvii 4.66 Spider plot for descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 15% and semi-sweet 20% chocolate chips ...... 133

4.67 Graphical representation of descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet 15% and semi-sweet 20% chocolate chips ...... 134

4.68 Spider plot for descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet 15% and semi-sweet 20% chocolate chips ...... 134

4.69 Graphical representation of descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 15% and semi-sweet 20% chocolate chips ...... 135

4.70 Spider plot for descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 15% and semi-sweet 20% chocolate chips ...... 135

4.71 Graphical representation of descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 15% and semi-sweet 20% chocolate chips ...... 136

4.72 Spider plot for descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 15% and semi-sweet 20% chocolate chips ...... 136

xviii CHAPTER I

INTRODUCTION

Dietary guidelines advocate three servings per day of fat-free or low-fat milk or milk products, such as cheese or yogurt, for children and adolescents of 9 years and older.

A report by Greer and Krebs (2006) entitled “Optimizing Bone Health and Calcium

Intakes of Infants, Children, and Adolescents” provides similar guidance. Calcium, magnesium and potassium are three of the five nutrients that are provided by the three servings of dairy products per day. Seventy-two percent of the calcium of the Dietary

Reference Intakes is supplied by milk and dairy products along with substantial amounts of protein, potassium, phosphorous, riboflavin, vitamin B12, zinc, magnesium, and vitamins A and D. Several studies that were conducted by Matkovic (1995) report that calcium intake during childhood and adolescence influence peak bone mass to help prevent osteoporosis later in life.

The cheese industry in the United States produces various varieties of cheeses to respond to various demographic preferences, with Cheddar cheese representing nearly one-third of the total cheese production (Casapia, 2005). The chocolate industry has countless varieties of chocolates available to consumers. The development and variations in flavor that occur during the maturation process of cheese and the interest in developing innovative products in the food industry has generated the idea of combining chocolate

1 and cheese. The comparison of four varieties of chocolates used in the preparation of corresponding processed chocolate cheese products and subsequent testing for consumer acceptability is one of the objectives of this project. The result shows promising potential growth in the sector of new product development in the future.

The use of a standardized sensory language will play a significant role to establish a reference guide for any food product for research and marketing purposes. Though the flavor lexicons for the aged and processed cheeses exist, it is a challenge to develop a sensory lexicon for the specialty cheeses. This can be achieved by ever expanding the horizons in the area of sensory descriptive terms by including various food and chemical references. Consumer preferences can be best demonstrated by analyzing the prepared products through consumer acceptability tests and descriptive analyses.

2 CHAPTER II

REVIEW OF LITERATURE

Cheddar Cheese

History

Cheese making began around eight to nine thousand years ago and is one of the oldest fermentations known. A museum in Baghdad, Iraq has an artifact showing

Sumerians milking cows about six thousand years ago (Soda, 1995). Salted cheese stored in earthenware pots can be found in the Egyptian tombs of King Horaha of the first dynasty (3200 BC) (Iskander, 1942). Greek and Roman civilizations also have the proofs and legends about cheese and cheese making (Jones, 1976). An Arabian nomad, Kanana, could possibly be the first person to have tasted cheese while traveling in a desert, where he had found his stored milk in a pouch made of animal skin, having been turned into a snowy white curd surrounded by a yellowish green liquid (Soda, 1995).

The town of Cheddar, in Sommerset, England was the origin for the manufacturing of the first Cheddar cheese. Cheddar cheese has different names in the

United States, such as American Cheddar, White Cheddar if it is uncolored, or “Vermont

Cheddar” (Casapia, 2005).

3 Production & Marketing

Nutritionally improved dairy products have often been successful in enhancing sales and distribution through expanding the line of innovative dairy products. New technologies in research are the liaisons to the industry. New dairy technology is necessary to improve the specific attributes like shelf-life, isolation or amplification of specific compounds, altering nutritional profile, and for the development of new functional characteristics. Food industries must analyze needs and desires of the consumer market to predict the most influential food products over the next 20 years. The food and dairy industries must target consumers in specialty niches in order to reach more consumers overall (Barkema, 1993; Senauer, 1990).

Two target groups that have great potential for dairy food marketing are the mature generation that consists of people older than 51 years and the baby boomer generation that consists of people from 34 years to 51 years old. The baby boomers will not grow old gracefully or follow the traditional lifestyle patterns of college, career, and parenthood followed by retirement. The expectations of the baby boomers are an improved quality of life through nutrition and exercise with independence, self- indulgence, and expectations that products will “do more” (Anonymous, 1997). Baby boomers are better educated than the other generations and demand information about all aspects of their lives. They will continue to live the lifestyle adopted in youth until they are impaired by the physiological changes due to aging (Anonymous, 1997). By the year

2040, an estimated 43 million American people will be over 85 years old (Duncan, 1998).

The physical changes in people will effect their attitudes significantly, such as

4 diminishment of smell and taste acuity, difficulty in chewing because of poor dentition, and prevalence of swallowing and digestive problems etc. (Anonymous, 1996; Berner &

Lofgren, 1991). Convenience is the bottom line for these generations and these generations will continue to drive the quest for innovative products to deliver taste, functionality, and value.

The physiological issues associated with the mature generation requires them to use easy-to-handle packages in appropriately smaller sized portions. Safety issues related to processing conditions to extend the shelf-life always remain a challenge. The technologies such as Ultra High Temperature (UHT) processing, modified atmosphere packaging and aseptic packaging open new avenues for extending shelf-life and distribution capabilities for the new generations of dairy products.

The current products that are being provided by the market are projected images of the innovative dairy products that are going to be developed. The greatest influence on this market is going to be by those people who make the recommendations to change it such as, scientists, students etc.

Fat, Moisture and Salt Contents of Cheddar Cheese and Interactions

Fat is a very important quality for sensory evaluation in terms of evaluating food products for flavor, color, texture and mouth feel. It is a precursor for many flavor components. It enhances the capacity of the senses to react with flavor compounds released in the mouth. This effect provided by the fat is unparallel to that of any fat replacer. Texture and flavor of Cheddar cheese are influenced by its total lipid content.

5 Weity, Marshall, Grun, and Ellersieck (2001) found that fat content affects the sensory profiles and the perceived sweeteners. Flavor perception is significantly affected by the presence of fat. Its presence contributes in changing the physical state of the food and facilitates the partitioning among saliva, receptors and head space in the mouth. Fat can interfere with tastants diffusing to receptors or entering the headspace and can also change the rate of regeneration of interfacial surfaces required for tasting (Forss, 1981;

Lim & Kim, 1989; Linch, Liu, Mela & MacFie, 1993; Overbosch, Afterof, & Haring,

1991). Whenever a fat containing substance is consumed, a layer of non-Newtonian semi- solid fluid is formed between the non-fat solid food and the skin. The coating of the tongue with melted fat decreases or prevents the perception of water-soluble flavorants

(Forss, 1981). The chemical composition of milk fat varies with the season, the region, the breed, and the animal feed used (Hawke & Taylor, 1983). The physiochemical properties of milk fat are too variable and a lack of functionality restricts its uses in the food industry (Deffence, 1993). Fractionation of milk fat into liquid and solid fractions, which differ markedly from one another in chemical composition and physical characteristics, facilitates an increased utilization of milk fat in many food applications

(Kaylegian & Lindsay, 1994). Consumers are demanding nutritious, flavorful, low fat foods. Bruhn et al. (1992) found that 90% of women and 75% of men are concerned with what they eat and the way it affects their health.

Also, several undesirable characteristics result with the cooking of cheese if the fat is removed from it. Those characteristics include poor melt, a tough and rubbery texture, translucent color and rapid skin formation. Fat globules normally act as fillers

6 between the protein fibers formed during the hot stretching of the cheese curd and reduce the interactions among proteins within the protein matrix (McMahon & Brown, 1984;

Oberg, McManus & McMahon, 1993; Paquet & Kalab, 1988).

Moisture content is an important factor in ripened cheeses which encourages the proper development of flavor and body, to improve keeping quality and bacteriological safety. Fat protects the protein fibers from dehydration during cooking by adsorbing heat energy (U.S. Patent No. 5,200,216, 1993) and retards the moisture evaporation. Thus, non fat cheeses which have high moisture content retain these characteristics, resulting in better melting characteristics of these cheeses. It has been claimed that melt can be greatly improved when the combined fat and moisture content of Mozzarella cheese is

•70% (Barz & Cremer, 1993). When the fat content of a cheese is reduced, the moisture is usually increased to compensate for the lower fat content (Abd El Rahman, Shalabi,

Hollender & Kilara, 1997). Increased moisture content can help to soften the cheese to avoid a rubbery texture; however, at higher moisture levels, the cheese may become so soft that it cannot be shredded or sliced (Hough, Puglieso, Sanchez & Silva, 1998).

Another pitfall of this method of increasing moisture without giving any consideration for the other parameters, such as water-holding capacity of the proteins, is continued syneresis that would occur after packaging, resulting in whey expulsion in the package

(Weity et al., 2001). There are several lower fat cheeses; namely reduced fat, lowfat, and fat-free cheeses, which demand an increase in the moisture content and a decrease in the fat content.

7 The moisture content of commercial Cheddar cheese may vary from <39% in full fat cheese to >50 % in low fat cheese, depending on the fat content (Mistry & Anderson,

1993). Hence, in lower fat Cheddar cheeses, the salt content in the moisture phase (SM) may be less than the optimum value of approximately 4.5%. It can be as low as 3.5%.

Lawrence, Heap, and Gilles (1984) suggested a SM of 4 to 6% for a premium grade New

Zealand Cheddar cheese. A decrease in SM content in lower fat cheeses facilitates excessive bacterial growth and proteolysis during cheese ripening (Kelly, Fox &

McSweeney, 1996; Thakur, Kirk & Hedrick, 1975), which might result in poor flavor development and flavor defects in these cheeses. Salt percentages in cheeses are important not only for flavor development but also for texture in cheese ripening as influenced by proteolysis (Guinee & Fox., 1993). An increase in the concentration of the salt can potentially decrease the proteolysis and bitterness. As a result, the catabolism of free amino acids produces compounds that directly contribute to the taste and aroma of

Cheddar cheese (Singh, Drake & Cadwallader, 2003). Salt alters the water binding properties of casein within the cheese matrix and helps to influence the physical properties of cheese (Cervantes, Lund & Olson, 1983, Ramkumar, Creamer, Johnston &

Bennett, 1997). Salting of the cheese enhances the water holding properties of the cheese matrix by increasing the hydration of the casein molecules, and it also helps to increase the amount of salt soluble proteins (Guo & Kindstedt, 1995).

The addition of salt to nonfat cheeses increases the interactions between proteins and surrounding water thus reducing the hydrophobic interactions that occur between protein molecules. Protein hydration in the cheese matrix facilitates moisture migration

8 into the small and large voids of the protein matrix. Addition of salt enables the ionic movement around the proteins, helping the various components in the cheese system to rearrange among themselves to attain minimum energy exertion. Cheese moisture content is inversely proportional to the salt content (Guinee & Fox., 1993), as it is observed that increases in whey expulsion takes place when the Cheddar cheese curd is salted

(Sutherland, 1974). Robertson, Dixon, and Nowers (1975) observed that addition of salt to whey before its expulsion from the curd heightened the moisture content of the cheese curd. The pore width of the protein matrix in nonfat curd has been observed (Guinee &

Fox, 1993) to be smaller than that of a cheese curd with higher fat content (Ca. 20% fat).

It reduces the diffusion coefficient by 30% and affects the way in which the cheese curd reacts with salt after adding it. Opacity of the cheese curd is possible when the salt is not added, and there are plenty of pockets of free serum which form an interface with the protein aggregates resulting in scattered light. Similarly, translucency in the salted cheese curd is possible because of the absorption of free-serum into the matrix making it a homogenous mixture, which leaves very few discontinuities for the light to get scattered.

Salting of cheese curd explains the better meltability of cheese as the hydrated protein aggregates dissociate more. Greater moisture content is a function of greater meltability, and this moisture is not the total moisture content in the cheese system, but corresponds to the one in the cheese matrix. Ratios of protein and moisture contents are very important as the moisture migrates into the protein matrix and fills up the voids that are being occupied by the serum pockets. Thus, salt helps to form hydrated protein matrices,

9 whereas the unsalted cheeses have the tendency to form larger protein aggregates with large pockets of serum existing within the protein matrix.

Flavor of Cheddar Cheese

The cheese system is the genesis for a wide range of chemical changes which can be attributed to its complex phenomenon called cheese flavor. Proper blend of taste and aroma are the two most important aspects of flavor. Flavor constitutes a composite of sensations. Mulder (1952) and Kosikowski (1958) suggested a “Component Balance

Theory”, a correct balance and concentration of sapid and aromatic compounds; in

Cheddar cheese to attribute to its flavor. Many volatile and non-volatile compounds are present in Cheddar cheese. According to Maarse and Visscher (1989), there have been more than 200 volatile compounds found in Cheddar cheese. Acetate, diacetyl, acetoin and 2,3-butandiol are the principal flavor compounds produced by the metabolism of citrate (Cogan, 1995).

Background flavor in Cheddar cheese and some off flavors including bitterness are due to the production of peptides and amino acids by the starter culture. Several sulfur-containing compounds such as methanethiol, methional, dimethyl sulfide, dimethyldisulfide, dimethyltrisulfide, dimethyltetrasulfide, carbonyl sulfide, and hydrogen sulfide attribute to the aroma of Cheddar cheese (Urbach, 1995). Off flavors in cheese can be attributed to the presence of high concentrations of acetate (Aston &

Dulley, 1982). Other off flavors can be caused by extensive lipolysis. Compounds such as

10 ethanol and phenylethanol esters, and ƣ and Ƥ lactones produced by the metabolism of fatty acids, play a vital role in flavor development of Cheddar cheese.

Non-cheddar types of cheeses, which undergo some characteristic fermentation, reveal the important relationship between cheese flavor and its parameters. A good flavored eight month old Swiss cheese is relatively high in propionic acid and as well as acetic acid, but it is relatively low in butyric acid content. The ripening of Blue cheese is characterized by considerable lipase action and the presence of intermediate and longer chain free fatty acids. The particular flavor of Provolone cheese can be attributed to the formation of free fatty acids during the lipase action with butyric acid being the characteristic compound of this cheese. Thus, a proper blend of chemical compounds is required to attain a good flavored cheese, suggesting that Provolone gets its characteristic flavor when glutamic acid and butyric acid are at the concentrations of 2 mg/g and 1 mg/g, respectively. Similarly, Swiss cheese obtains its characteristic flavor when the blend of chemical compounds such as proline and propionic acids have reached levels of

2 mg/g and 4 mg/g, respectively (Harper, 1959). A complete understanding of cheese flavor facilitates controlling the uniformity of flavor and helps manufacturers provide consistent quality cheeses to the consuming public.

Texture of Cheddar Cheese

The texture of Cheddar cheese is identified by consumers as one of the most important attributes that determines the quality of cheese (McKwan, Moore & Colwill,

1989; Jack, Paterson & Piggot, 1993). Cheese is a viscoelastic material that is formed by

11 a continuous network of casein in which fat globules and water are interdispersed

(Prentice, 1987). Textural properties of Cheddar cheese constitute geometrical (shape, orientation) and mechanical characteristics (hardness, cohesiveness, elasticity and adhesiveness, brittleness, chewiness, and gumminess).

Cheese texture is mainly related to pH and the intact casein/moisture ratio

(Lawrence et al., 1987). This also serves as an index for the primary proteolysis. The pH of the curd is related to chemical changes in the protein matrix and this affects the cheese texture. The decrease in pH also influences the decrease in the amount of colloidal calcium and the binding capacity of protein. The structural units of the protein network in the cheese at pH 5.2 are the same as that of milk submicelles. The protein assumes compact conformation below pH 4.8, and is near the isoelectric point (Lawrence et al.,

1987).

A language for Cheddar cheese texture has been identified and referenced (Drake,

Gerard & Civille, 1999), however this language for Cheddar cheese was specific and can only be used for product specific scaling, but not for universal scaling. The texture and viscosity of food material influenced the perceived intensity of flavor (de Roos, 1997;

Leland, 1997).

Descriptive Sensory Language for the Evaluation of Cheddar Cheese

Descriptive analysis refers to the characteristics (qualitative aspect) that define a product with different terms (attributes, descriptors, etc.), and the intensities (quantitative aspect) to which those characteristics are perceived (Meilgaard, Civille & Carr, 1991).

12 Arthur D. Little developed a Flavor Profile Method (FPM) in 1950, and it was the first published descriptive sensory technique (Pangborn, 1989). Standards of identity for any food product are pressing demands. The description of a food item in terms of its chemical and physical form is vital. The product definition is incomplete without the sensory profile, an objective description of appearance, smell, aroma, taste and texture.

Sensory profiling is a must in understanding the framework of cheeses. The most widely studied sensory profiles of cheeses are Cheddar, Emmental, Parmigiano Reggiano and Comteƍ cheeses. The substantial variation in sensory profiling methods depends upon a range of factors, such as panel of assessors, a tasting protocol (e.g., defining sample numbers, sample dimensions, order of tasting and degree of repetition), a sensory vocabulary (a list of descriptors) and a user-friendly method of presenting all the results.

To develop a sensory vocabulary, the nature and size of the list of descriptors are taken into account to characterize a particular cheese. The method of profiling is generally quantitative descriptive analysis with the development of vocabulary being the most important factor. The variation in sensory profiling is due to the interpretation of a particular term in different geographical locations. Interpretation of sensory profiling data is often influenced by cultural and linguistic effects (Coggins & Chamul, 2004). For example, fruity in the USA is connected with sugar content, where in Spain and

Switzerland, it is ester content (Daget, 1992).

Any descriptive analysis on cheese should mainly assess the strengths and weaknesses of the different sensory methodologies adopted to analyze the cheese samples. Commonality should exist among the other descriptive analyses of the same

13 product. While analyzing cheeses using descriptive sensory analysis, significant trends in that particular demographic area should be taken into consideration. Cheese types with particular sensory characters all belonging to the same family of cheeses, provide an excellent opportunity to come to a common consensus among the food sensory experts to categorize them accordingly. And, samples which expand the range of sensory stimuli are normally given a pronounced interest.

The ideal methodology being adopted to analyze cheeses includes the following common criterion. Cheese is purchased and the cheese portions are vacuum packed and refrigerated to 2+1°C prior to shipping. Insulated boxes with reusable freeze packs and a sample of water helps in the shipment of cheeses to laboratories for analysis. It is advisable to record the date and time of the arrival as well as the holding temperature.

Typically, cheeses for analysis are served at a temperature of 16±1°C. The size of samples to be served is decided according to the requirement of the test protocol. The laboratory which is carrying out the test is expected to provide information on which order the samples are being served, the kind of neutralizing agent used (water, biscuits, crackers, etc), the number of samples analyzed in each session and the degree of repetition in analyzing the samples. The results that panelists provide may be analogous to those obtained by Quantitative Descriptive Analysis (QDA®). The panelists are asked to evaluate appearance, aroma, and texture using a structured or unstructured scale. The standard layout of the data is desirable if it contains aspects such as repetition (if appropriate), assessor, session, order of presentation within session, sample code and ratings for each attribute (Nielsen et al., 1998). The results of the statistical evaluation of

14 the data determine whether a second trial is required. Although distinct in the approach, all the methods have a commonality as far as whether they are quantitative or qualitative.

Most of the sensory attributes are the same in different approaches. Skilled assessors are employed in most of the panels. All the samples for the test are treated the same with regard to temperature, serving method and storage conditions. However, conducting repeated assessments is optional. To describe the intensity of an attribute, all scales used for rating in quantitative description may not be suitable. There is a considerable degree of uniformity lacking in the use of attributes. The statistical methods employed generally show that the data are divided into three modalities such as appearance, aroma, and texture. Consensus space is determined by using Generalized Procrustes Analysis (GPA)

(Nielsen et al., 1998). Then, Principal Components Analysis (PCA) is used to find the principal sensory dimensions for each modality and are interpreted by correlating the scores with the means for each sensory descriptor. The key words to determine an underlying attribute are selected through Multivariate statistical analysis by GPA, correlating the scores of principal sensory dimensions of each attribute with the means of that attribute, grouping the words by correlation diagrams, listing the words that closely relate in meaning, tabulating the most frequently used words and their synonyms and final selection of the list of attributes and their explanation (Nielsen et al., 1998).

Grading and judging are extensively used by the dairy industry for quality evaluation of all dairy products (Bodyfelt, Tobias & Trout, 1988). The overall quality scores that are given to assess the product are subjective rather than specifically defined

(Bodyfelt, 1981). Description of all the attributes and intensities of flavor attributes in

15 cheese is very useful for niche market identification and for end product application.

Heisserer and Chambers (1993) developed a sensory language for hard cheeses, however that language was not specific for Cheddar cheeses. Several collaborative studies in

Europe (Hirst, Muir & Naes, 1994; Hunter & McEwan, 1998; Nielsen et al., 1998) took place to develop a common sensory lexicon for hard cheeses. Ideally, a descriptive language should be developed from a representative sample set (Meilgaard et al., 1999).

Similarly, standard descriptive languages have been developed for other commodities using a representative sample set and a group of panelists to generate terms (Johnson,

1986; Johnson & Civille, 1986; Johnson, Civille, & Vercellotti, 1987; Janto,

Pipatsattayanuwong, Kruk, Hou & McDaniel, 1998). Analysis of variance with mean separation is used to evaluate panel consistency across replicates of the same cheese sample. To identify redundant terms and to differentiate the different cheeses, principal component analysis and factor analysis using treatment means is used. Individual relationships between terms are identified by using correlation analysis in which statistical significance is adjusted using Bonferroni’s adjustment (Miller, 1980). In

Ireland, Murray and Delahunty (2000a, 2000b) identified references for a Cheddar sensory language. Cross-cultural differences may account for the differences in the terms and their description, the references used to describe the descriptors, and thus a potential area of future research (Risvik, Colwill, McEwan & Lyon, 1992; Hirst et al., 1994).

References for the descriptors may not necessarily be identical to the described flavors, but they should be sufficiently similar to identify a specific term for which the panelists have been trained. Sometimes, it is needed to potentially separate some specific terms

16 and Berodier, Stevenot, and Schlich (1997) explained a similar hierarchy of terms with a lexicon for comte´ cheeses. Heisserer and Chambers (1993) reported fruity and pineapple terms as two distinct flavors in the study of hard cheese flavors. Generally, a basic outline of the terms would be sufficient to explain the attributes of Cheddar cheese. But, sometimes there might be a need for extra attributes which do not conform to the standard outline. For example, descriptors such as fecal, oxidized, rosy/floral, bell pepper, moldy/musty, and prickle/bite are typically not listed in the attributes of Cheddar cheese.

Quantitative Descriptive Analysis (QDA®) and the SpectrumTM methods are more recent applications of sensory analysis. More panelists, about 8-12, are needed in QDA when compared to Flavor Profile Method (FPM). The panel leader in the QDA and

SpectrumTM method facilitates the discussion to generate the flavor attributes and terms, where in FPM this is not done (Stone, 1992).

Principal component analysis (PCA) is carried out basically to identify non- redundant terms that differentiate the cheeses. Principal component analysis determines the high correlations between mouth and hand evaluated attributes such as slippery, etc.

To clarify further the group of attributes, factor analysis with Varimax (SAS. 2006,

V.9.12) rotation is applied to the correlation matrix of cheese attributes. Generally, the young undeveloped flavors in cheese are cooked, whey, diacetyl, and milk fat. Common aged flavors are considered to be fruity, sulfur, free-fatty-acid, brothy, nutty and catty.

Cowy/barny flavors are linked to the chemical component p-cresol in cheese and considered as an undesirable flavor in American Cheddar cheeses (Dunn & Lindsay,

17 1985; Suriyaphan, Drake, Chen & Cadwallader, 2001). Heisserer and Chambers (1993) reported inability to differentiate sweet and sour aromatics from sweet and sour tastes, respectively. The standardized, developed and referenced language was developed for

Cheddar cheese using the SpectrumTM method and scales (Meilgaard et al., 1999).

References for the basic taste intensities are available in Meilgaard and others (1999).

This method uses universal intensity scales.

Aged Cheddar Cheese

The many chemical reactions that take place during the ripening of cheese, (ie glycolytic, lipolytic, and proteolytic reactions) are responsible for the flavor development in cheese (McSweeney & Sousa, 2000). These chemical reactions trigger the degradation of major milk constituents such as lactose, citrate, milk lipids, and casein during ripening

(Singh et al., 2003). The other chemical reactions consist of catabolic changes, including deamination, decarboxylation, and desulfurylation of amino acids, ȕ- oxidation of fatty acids and synthetic changes such as esterification (Fox, 1993). Most cheese varieties require a period of ripening for development of flavor and texture characteristics

(Folkertsma, Fox & McSweeney, 1996). Hydrolysis of triglycerides during ripening produces free fatty acids, di-and monoglycerides and glycerol which attribute to the aroma of cheese.

The considerable inventory cost associated with storage has stimulated interest in accelerated ripening (Folkertsma et al., 1996). The methods followed for this purpose are elevated temperatures, addition of exogenous enzymes, use of genetically modified

18 starters, addition of non-starter lactic acid bacteria as adjunct starters and addition of cheese slurries. Cheese ripening is an important phenomenon from the stand-point that a hard rubbery mass of cheese is being converted into a smooth-bodied and a full-flavored product by the gradual breakdown of carbohydrates, fats, and proteins.

Processed Cheese

Natural cheese is generally considered a commodity product, but processed cheese a value-added product. Natural cheese is more of a living system in which several attributes prove to be quite variable. Processed cheese formulations are custom-designed and are often a specific and constant composition. Blending of two or more natural cheeses, with the addition of an emulsifying agent along with other approved optional ingredients under high temperatures, yields processed cheese with a uniform melt and smoothness without any oiling off.

For shredding or chipping, frozen varieties are excellent, where as for melting and for incorporating into doughs, the refrigerated versions are used. Lipases are blended with natural cheese to produce an enzyme-modified cheese (EMC) with more intensified flavor development. The dicing or shredding or crumbling reduces time for melting cheese. Separation of the fat and denaturation of the protein are caused by subjection to high temperatures for prolonged periods of time. If cheese has to be applied as a topping on a product that needs baking, then the cheese should be covered in the form of crumbs to prevent toughening or hardening. Hard cheeses of Italian-style are better used as an ingredient because they do not form denatured protein threads when heated. The other

19 types of Italian-style cheeses, such as Mozzarella provides string and stretch as the cheese curd is stretched in a hot-water system during manufacturing, which enables the protein structure to elongate. Heat-catalyzed brown pigment is formed on baked/cooked

Mozzarella cheese because of the presence of galactose. Reduced fat products or fat-free products using the cheese can be formed by utilizing a small amount of highly flavored cheese or a mixture of two or more of such cheeses. Lowfat or skim milk, nonfat milk solids or fat replacers such as starches, gums or proteins may be employed in the preparation of reduced fat and fat-free cheeses. These cheeses are higher in moisture and have a firmer texture. Though the shelf life of cheese is greatly improved when stored with a reasonable moisture content (U.S. Patent No. 3,531,297, 1968). Defective free melt can be obtained by cooking at lower temperatures for longer periods of time.

Recently, heat stable cheese fillings are flooding the market. The water activity for such fillings remains in the 0.65 - 0.70 (Aw) range to ensure microbial safety of the product. Shelf stability is about 6 months for such products. The mild or sharp Cheddar fillings can have inclusions of bacon bits, sun-dried tomatoes or dehydrated vegetables.

The product can be accented with a myriad of diverse flavors as well. Snack formulations typically have 30-60% filling and the fillings are firm at room temperature and can be squeezed or pumped since they are soft at 80 °F (26.7°C).

Recently, to boost the calcium intake for chidren, cheese-flavored products are also being introduced. Dairy Management Inc.®, the planning and marketing organization that helps to build demand for U.S. produced dairy products, oversaw the development of a process to create multiple flavored cheeses.

20 There are three generations of cheese products that have been basically developed during the last fifty years.

First Generation

First Generation includes the use of natural cheese which uses fluid milk. It is known as processed cheese category and includes 50% of the total cheese production in the USA. These products have been in the market for the past 50 years.

Second Generation

Second generation includes the products which do not use fluid milk, and the dairy fat has been substituted with vegetable fat. These products constitute 10% of the total cheese production and have been in the market for the past 20 years. These do not contain cholesterol and cost half of the price of natural cheese.

Third Generation

The first product under the third generation was developed through the cooperation of two companies, namely The Cheese Foods International, Ltd. of the USA, and the Palsgaard Industri, A/S. of Denmark.. This group contains the cheeses in which fat and protein of vegetable origin are used. This generation of cheeses is still under the experimental stage. Basically in the third world countries where milk is scarce, these cheeses can be made from ingredients of vegetable origin. Protein is the most difficult thing to incorporate as an ingredient. The available casein protein has reached its

21 maximum output potential with the ever increasing demand of cheese production worldwide. Several combinations of ingredients can be prepared to replicate the functional properties found in the original cheeses. For example, wheat gluten contributes to the stretchability of Mozzarella cheese. Readily available soybean protein, improves the amino acid profile of the other proteins and is a relatively low cost protein.

Developments in this category are underway and many countries are taking several steps to explore this area of research.

Swiss and Italian cheeses use Lactobacillus strains as starter cultures and these play an important role in the ripening process (Wouters & Ayad, 2002). Highly proteolytic bacteria have an important role to play in improving cheese quality, to accelerate cheese ripening, to develop cheese flavor, and to debitter the bitter protein hydrolyzates. In order to develop a starter culture with defined proteolytic properties, it is necessary to learn and understand the complete activities of the Lactobacillus species.

Takafuji, Iwasaki, Sasaki and Tan, (1995), investigated 169 highly proteolytic

Lactobacillus strains of 12 species and they came to a conclusion that the Lb. helveticus

SBT 2171 strain has the highest activity towards most of the peptide substrates tested, has the highest debittering activity, and the proteolytic enzymes that are used by this strain are different than those that are used by Lactococcus.

Global production of Mozzarella cheese has grown dramatically during the period

1985 to 2000 (Rowney, Rupas, Hickey & Everett, 1999), especially in the United States where annual production in 1996 was ~1.03 million tonnes (IDF, 1997). This can be attributed to the fact that Mozzarella is being used extensively due to the popular pizza

22 industry. The use of speciality cheeses in pizza making are mainly due to the properties of flow and stringiness upon baking, especially stretchability. Such cheeses come under the category of the pasta filata group and it includes Mozzarella, Provolone, and

Kashkaval (Fox, Guinee, Cogan & McSweeney, 2000). The manufacturing of these cheeses involves plasticization of the fermented curd (pH 5.1 to 5.4) during which it is scalded (to 57°C), kneaded and stretched in hot water or dilute brine (80°C). The conditions of low pH and high temperature are conducive to limited aggregation of para- casein and the formation of para-casein fibers of relatively high tensile strength (Kimura,

Sagara, Fukushima & Taneya, 1992; Taneya, Izutsu, Kimura & Shioya, 1992). These fibers impart stretchability, stringiness and chewiness to the melted cheese topping when they are cooked on pizza (Fox et al., 2000). Thus, it is a well accepted fact that the pH and Ca concentration influence the ability of cheese curd to plasticize in hot water or dilute brine. During the manufacturing of pasta filata cheeses, the pH of cheese curd is lowered before it is subjected to plasticization, as lactose is converted into lactic acid.

This reduction of pH in the curd before plasticization facilitates several physiochemical changes such as solubilization of micellar calcium phosphate (van Hooydonk, Hagedoorn

& Boerrigter, 1986), an increase in the ratio of soluble to colloidal Ca (Guinee,

Harrington, Corcoran, Mulholland & Mullins, 2000), and an increase in the para-casein hydration (Creamer, 1985). The functional properties of Mozzarella cheese are influenced by many factors including milk pretreatment, processing procedure, composition, and proteolysis (IDF, 1989; McMahon, Oberg & McManus, 1993; Kindstedt, 1995; Madsen

& Qvist, 1998).

23 Innovations or New Trends in Processed Cheese Technologies

According to Jacobs (1951), pasteurized processed cheese is the food prepared by comminuting and mixing, with aid of heat, one or more varieties of cheese with emulsifying agents into a homogeneous plastic mass. The origin of manufacturing processed cheese occured from 1905 to 1911 at the Swiss factory of Gerber & Co. while trying to develop a new method of preserving cheese (Bauertal, 1932). The first processed cheese in America was developed before World War I (Kosikowski, 1966). A key patent was issued in the year 1918 by John Kraft which involves the heating of natural cheese and its emulsification with alkali salts. According to Price and Bush

(1974), the objectives of processing cheese were to extend the keeping quality of cheese and to deliver it to consumers in a convenient form. Originally Swiss and Cheddar cheeses were the only cheeses used for processing (Bauertal, 1932). Later on, several other varieties of hard cheeses were used for processed cheese production.

Processing of cheese improves the water-soluble nitrogen in the cheese

(Templeton and Sommer, 1930). Bauertal (1932) suggested that a variety of spices such as caraway, nutmeg and cloves could be used. Whole milk, condensed whey, cream and other substances could also be included. According to the United States Federal

Standards of Identity, processed cheese should not contain more than 3% emulsifying salts with the moisture and fat contents equal to the natural cheese from which it was derived (Kosikowski, 1966). Pasteurized processed cheese must not contain more than

40% moisture and must not contain less than 50% fat on a dry basis. According to Jacobs

(1951), pasteurized processed cheese must contain not less than 51% cheese, not less than

24 22% fat on a dry basis, and not more than 44% moisture. Lack of acidity, low fat content and excessive moisture are some of the defects of processed cheese (Templeton &

Sommer, 1930). Different parameters such as the age of the natural cheese, common salt, pH, emulsifiers, processing temperature, moisture content and the casein to-fat ratio affects the body and texture of the processed cheese. Gassy fermentation is likely to happen when the cheese has been processed under 60°C (Templeton & Sommer, 1930).

Firmness in the body is consistent between 60°C and 65.5°C, but above this temperature firmness increases significantly. According to Templeton and Sommer (1930) when cheese is processed at temperatures higher than 68.3°C, there is a change in the color.

The texture of processed cheese changes in the cooking kettle (Kosikowski, 1966), and he recommends a cooking temperature of 65.5°C-71.1°C with a holding time of 3 minutes. Kosikowski also mentions that cooking for 5 minutes at a desired temperature and holding it for 3 minutes and then emptying all the contents within this time period protects the cheese flavor. The fat separation is significantly influenced by the velocity of agitation, the moisture content, the acidity and age of cheese (Bauertal, 1932a).

Emulsifiers

The emulsification system is a key factor of restricted-melt cheeses such as processed cheeses. The commonly used emulsifiers in processed cheese manufacture are sodium citrate, di-sodium phosphate, and sodium potassium tartrate (Rochelle salt)

(Bauertal, 1932). Sodium citrate is a better emulsifier when compared to di-sodium phosphate, as it facilitates decreased separation of the fat during the process of heating

25 and provides the cheese with firmer body and preferred flavor (Templeton & Sommer,

1930, 1932, 1937, 1938). Di-sodium phosphate gives a very soft product with very poor fusion. Methyl cellulose as an emulsifier has the combined properties of hot gelation and cold gelation. Methylcellulose immobilizes water at cold temperatures and thickens to reduce the excessive melting at elevated temperatures. The emulsifiers act as surfactants to displace protein at the air-serum interface and create an unstable monolayer with respect to bubble collapse (Dickinson, 1992). For example, the amount of foaming is significantly reduced in cream cheese dressing when polysorbate 80 is added to it.

Defoaming emulsifiers function very effectively in reducing the air incorporation during the processing of cultured dairy products.

Stabilizing ingredients in dairy products interact with milk proteins, water and other stabilizers to immobilize the water and to modify the gel structure. Except for emulsifiers, ingredients in the stabilization system function in the continuous phase or in the serum.

Chocolate

Many confectionary historians site that somewhere in the Indian subcontinent in roughly 500 B.C., the technology to press and crystallize juice from sugarcane first came under human control. Even Hindu texts as old as the Mahabharata and Ramayana, written between 600 B.C. and 200 A.D., describe several pseudo candies (Decker, 2006). Soon,

Ancient Persians spread the cane-boiled sucrose to the Tigris and Euphrates valley where it was used it in confections. During the time when Islam was rising to power during the

26 7th century, Arabs carried sugar and its confections across North Africa, Spain, Sicily and other Southern European outposts. Chocolate’s history is fascinating and unique as it spent its first few millennia of existence as a beverage (Decker, 2006). The author

Harold McGee (2004) writes in “On Food and Cooking: The Science and Lore of the

Kitchen”, that not until 1828 did chocolate become practical as a solid food when

Dutchman Conrad van Houten designed a screw press capable of removing enough excess cocoa butter from ground beans to remix with ordinary cocoa producing a “paste more malleable, smoother, and more tolerant of added sugar” than drinking the cocoa.

Standards of identity for chocolate with cocoa butter and chocolate liquor require preservation by processing to temperatures between 15°C and 17.2°C and a relative humidity below 50% {Boutin, R. study (as cited in Decker, K. J., 2006)}. Cocoa powder consists mostly of fat-free cocoa components and a minor portion of fat (cocoa butter).

The fat-free elements in cocoa powder determine the color of the chocolate, which mainly consists of high amounts of sucrose and cocoa butter.

Chocolates are prepared from the beans of a genus of the Theobroma tree (Matz,

1972). Two revolutionary developments in chocolate making occurred during the nineteenth century {Chocolate manufacturers association (CMA) study (as cited in

Liewkasamesan, 1980)}. The first was the making of a milk chocolate for eating by

Daniel Peter at Veves in 1876 and the second one was the subsequent development of a fondant chocolate. Matz (1972) defines cocoa as chocolate fibers from which a substantial proportion of the fatty material has been removed. Dutch processed cocoa

27 refers to cocoa powder made from nibs and liquor, which has been treated with alkali to neutralize the natural acids present (Gott & Van Houten, 1958).

Chocolate has several significant flavor notes. The balance of the flavor profile is due to reactions and losses of certain flavor components in chocolates. Changing the balance of the flavor profile of chocolate can produce a harsh flavor (Bodyfelt et al.,

1988). Aldehydes, ketones and alcohols contribute significantly to many types of food products. Chocolate flavor has high concentrations of isovaleraldehyde and phenylacetaldehyde, as well as lower concentrations of benzaldehyde, all of which are important to the flavor (Gill, MacLeod & Moreau, 1984; Keeney, 1972). Pyrazines, also important in chocolate flavor, are formed via the Maillard reaction during the roasting process of cocoa production (Arnoldi, Arnoldi, Baldi & Griffini, 1988). The concentration of pyrazines increases as the roasting of the cocoa beans increases. Many of the pyrazines have a nut-like aroma similar to that of peanuts (Keeney, 1972).

Pyrazines lose water solubility as they become more complex and more alkyl-substituted.

Chocolate liquor has 55% cocoa butter fat, where cocoa contains 10 to 25%. Prindiville,

Marshall, and Heymann (1999) found that as fat concentration decreased, the intensity of cocoa flavor, cocoa aftertaste, and chocolate aftertaste increased when tested by a descriptive analysis panel.

More than 500 volatile compounds have been detected in cocoa and they all react differently with milk fats and fat replacers. Pyrazines, aldehydes, ketones, furans, other carbonyls, alcohols and esters are some of the important flavor volatile compounds found in cocoa powder (Prindiville et al., 1999). Cocoa powder also has theobromine, caffeine,

28 and other compounds that give bitter and sour tastes. Cocoa butter and milk fat have a euteric interaction that may affect flavor release during the consumption of chocolate ice cream (Timms, 1980, 1994). Hatchwell (1994) found that chocolate ice cream without milk fat lacked creamy, milky, and chocolate-like flavors and instead was described as dark, woody, fudgy, and reminiscent of a dirty ashtray. For example, chocolate ice creams containing more than 0.5% milk fat are significantly higher in off-flavors though there was no consistent pattern of off-flavors. Hence the decrease in milk fat from 6% to

0.5% heightened the cocoa flavor. However, it is not well documented whether it is due to the abilitiy of milk fat to dissolve the flavor volatiles or due to its ability to modify the physical structure of cocoa making its flavor pronounced.

Processed Chocolate Cheese

Shostak (1929) developed a form of chocolate cheese which required adding an emulsifier to melted cheese. Hedrick (1971) experimented at several pilot plant operations on the manufacturing of a chocolate flavored confection using natural mild cheddar cheese as a base. Sensory testing on these prepared products revealed some strong flavored varieties of cheeses that provided several acceptance problems despite the type of chocolate used. A formula originally developed consisted of 41 pounds of mild- flavored cheeses, 29 pounds of powdered sugar, 13 pounds of non-fat dry milk (NFDM),

12 pounds of salted butter (U.S. Grade A or higher) and 5 pounds of cocoa (Dutch processed) (Liewkasamesan, W., 1980) . Hedrick (1971) suggested the use of vegetable fat in place of the butter fat. Hedrick (1971) suggested two methods to develop the

29 chocolate flavored cheeses. The first, the blending of the cheese mixture into a smooth, homogenous mass. The second, more time consuming, involved the addition of melted butter (or vegetable fat) to the confection bowl once the cheese was processed through a food grinder just before being fed into the bowl. All the dry ingredients such as sugar, non-fat dry milk (NFDM), and cocoa were mixed together and added to fat and cheese and slowly heated to a temperature of 65.5°C for 30 minutes. The product so prepared contained 82.10% total solids, 24.70% fat and 16.40% protein. Gott and Van Houten

(1958) suggested the use of common nuts, almonds, Brazil nuts, cashew nuts, peanuts, pecans, and walnuts in combination or independent in one or more varieties. LeDrew (as cited in Decker, K. J., 2006) has tried chocolates laced with notes of olive oil and Italian cheeses.

The new innovations in processed cheese technology have supported the idea of developing chocolate cheese. In developing confectionary formulations, formulators must consider several aspects such as ingredient performance and handling characteristics

(Zeiher, 2006). Over the years, different types of milk powders have been used in combination with chocolates (Haylock, 1995). Sharp cheeses because of their rancid, acid and bitter flavors adversely react with cocoa, where as mild cheeses can mask those off flavors to give a pleasant taste.

30 CHAPTER III

PRODUCT FORMULATION AND CONSUMER ACCEPTABILITY OF PROCESSED

CHEESE MADE WITH DIFFERENT TYPES OF COCOAS AND CHOCOLATES

Abstract

Four different types of chocolates and cocoas were processed to produce corresponding processed chocolate cheeses which were evaluated for consumer acceptability. Varieties were tested for four basic attributes such as texture, appearance, flavor, and overall liking. The products were also ranked according to their preferences of the consumers.

The four treatments were significantly different with respect to overall liking where as the other attributes were not different. Descriptive sensory attributes, if evaluated, would provide a better understanding of these new products.

Key words: Processed chocolate cheese, consumer acceptability, chocolate and cocoa.

Introduction

Processed cheeses including different varieties of chocolates and cocoa have been evaluated for various parameters such as appearance, flavor, texture, and overall liking.

The formulations for the processed cheeses included the incorporation of different types of chocolates and cocoa. The contribution of the chocolate to the cheese in terms of its prominent sensory characteristics was observed by employing consumer panels. The

31 finished product was also evaluated for its consumer acceptability. Chocolate can be a value added application for this new cheese product. The marketing efforts in launching this new product would depend upon its ability for the specific flavor development to draw the attention of different ethnicities.

The use of affective sensory technique such as consumer acceptability in developing new processed chocolate cheeses would provide an overall evaluation of attributes and/or ingredients or process variables that motivate overall acceptance in the market. Storage temperatures, packaging parameters, and also shelf life are the further potential areas of this research. It would help to understand the complete nature of the product if a descriptive sensory study is carried out.

The general formula as suggested by Hedrick (1971) of Michigan State University was used as a guideline. The basic formula as suggested by Hedrick (1971) consisted of natural cheese, sugar, NFDM, vegetable fat and cocoa. Similar guidelines were also derived from the work done by Wanna Liewkasamesan, (1980) at Mississippi State

University. He studied various processed chocolate cheese products using a consumer panel at Mississippi State University. According to this guideline, a duplicated formula was used from his work and sodium citrate with cream also added to the new product.

32 Materials and Methods

Equipment and Materials

The laboratory equipment included a digital thermometer (Acurite, NSF model number 00640) and GROEN Steam Jacketed Kettle, (SN-1973, Model TDB/4-20,

208 Volts, Maximum Water Pressure 50 psi at 300 °F). Commercially available fine granular tri-sodium citrate dehydrate (YIXIN, Union-Biochemical Co., LTD., Jiangsu,

China) was used as an emulsifier and was obtained from the Custer dairy processing plant at Mississippi State University. Different chocolates and cocoas (Baker’s German’s

Brand sweet chocolate bar {Kraft Foods, Northfield, IL}, Ghirardelli chocolate as sweet ground chocolate and cocoa {Ghiradelli Chocolate company, San Leandro, CA},

Bordeaux semi-sweet chocolate coating {Archer Daniels Midland, Milwaukee, WI}, and

Dutch processed cocoa {ADM, Milwaukee, WI}) were used. Other ingredients included in the preparation of processed chocolate cheese products: Granulated sugar (Kroger,

Cincinnati, OH), non-fat dry milk (NFDM) (Kroger, Cincinnati, OH), vegetable shortening (Crisco, J. M. Smucker, Orrville, OH), natural mild cheese (Kroger,

Cincinnati, OH), whey powder (Edward W. Custer dairy plant at Mississippi State

University), and Grade A cream (36% milk fat) (Kroger, Cincinnati, OH) (See page no.

142 and 143 for the brands).

Formulations and Laboratory Processing of Chocolate Cheese

A used Groen steam jacketed kettle with 20 - quart capacity constructed of stainless steel was used. The mixing bowl in the kettle has the dimensions approximately

33 35.56 cm dia × 30.48 cm deep. This was a self contained 50 psi at 148.8°C steam jacketed electric kettle. It is equipped with a tilt handle to facilitate the operation of the kettle. For the safety of operating the kettle, the unit is equipped with an adjustable thermostat and safety valve. It also includes a heating indicator light, a support housing and pressure gauge to monitor kettle operation.

The steam jacketed kettle was cleaned with a hot detergent solution (Labconco®) and sanitized with 200 ppm chlorine solution before starting the operation. The water level gauge was set to 1.27 cm by opening the valve and filling the jacket. The pressure gauge was read and it was made sure to read 20 to 30 psi. If it was 0 psi before starting the operation, then the kettle was heated until pressure was 5 psi and the safety valve lever was lifted to vent the excess air. The electric power was turned on to the unit. The thermostat dial reads 0 through 10 and it was turned to low heat (dial position at “1” through “4”).

The natural mild cheese was grated and mixed with tri-sodium citrate. The vegetable shortening was placed into the kettle and mixed with natural mild cheese and tri-sodium citrate. This mixture was heated while constantly raising the temperature to medium heat (dial position at “5”) as indicated by the heating light. The cycling of the light on and off indicated that the kettle was adjusting itself to a temperature associated to the dial position. Once the cheese mixture (cheese and tri-sodium citrate) started melting, the dry ingredient mixture (cocoa powder or chocolate, NFDM, sugar and whey powder) and cream were alternately added four times during the processing and agitated constantly by using a whisk (Hodges Company, Washington, DC). Care was taken to

34 constantly fold and blend the mixture by using a Farberware® plastic spatula that can withstand temperatures up to 204°C. Proper mixing inhibited fat separation during the processing. The temperature was gradually raised and set on high heat (dial position at

“8”) as the cheese melted. Constant checking of the temperature was done by using a digital thermometer (Acurite, NSF model number 00640). Once it reached 74°C, the timer was set and the product was cooked for 5 minutes.

The cooked product was poured into 20 cm by 20 cm non-stick pans (Oneida

Company, Oneida, NY). The pans were covered with aluminum sheets (Reynolds

Company, Dallas, TX) to prevent any moisture absorption from the air. The products were rested at ambient temperature about an hour, and then stored in the refrigerator

(VikingTM Professional, Model VCSB483) at the Garrison Sensory Laboratory at a temperature of 5°C for approximately 14 to 15 hours. Four treatments using four different varieties of chocolates and cocoas were replicated three times. Each batch for each treatment weighed approximately 1000 g. (Tables 3.1 to 3.4).

Table 3.1: Final formulation of processed chocolate cheese using German chocolate.

Ingredient % of the ingredient in the total product Per batch (in g) Cheese 43.90 439.00 Sodium citrate 1.65 165.00 Sugar 17.58 175.80 Non-fat dry milk 8.79 87.90 Vegetable shortening 6.60 66.00 Whip cream (36% milk fat) 8.23 82.30 German Chocolate 4.46 44.60 Whey powder 8.79 87.90 Total 100.00 1000.00

35 Table 3.2: Final formulation of processed chocolate cheese using Dutch cocoa.

Ingredient % of the ingredient in the total product Per batch (in g) Cheese 43.90 439.00 Sodium citrate 1.65 165.00 Sugar 17.58 175.80 Non-fat dry milk 8.79 87.90 Vegetable shortening 6.60 66.00 Whip cream (36% milk fat) 8.23 82.30 German Chocolate 4.46 44.60 Whey powder 8.79 87.90 Total 100.00 1000.00

Table 3.3: Final formulation of processed chocolate cheese using Ghirardelli chocolate.

Ingredient % of the ingredient in the total product Per batch (in g) Cheese 43.95 439.50 Sodium citrate 1.64 16.40 Sugar 13.71 137.10 Non-fat dry milk 8.79 87.90 Vegetable shortening 6.60 66.00 Whip cream (36% milk fat) 8.23 82.30 Ghirardelli Chocolate 8.29 8.29 Whey powder 8.79 87.90 Total 100.00 1000.00

Table 3.4: Final formulation of processed chocolate cheese using Bordeaux chocolate.

Ingredient % of the ingredient in the total product Per batch (in g) Cheese 43.90 439.00 Sodium citrate 1.65 16.50 Sugar 17.58 175.80 Non-fat dry milk 8.79 87.90 Vegetable shortening 6.60 66.00 Whip cream (36% milk fat) 8.23 82.30 Bordeaux Chocolate 4.46 44.60 Whey powder 8.79 87.90 Total 100.00 1000.00

36 Consumer Acceptability using Sensory Testing

A consumer panel was conducted to test and compare the products. The samples were taken out of the refrigerator two hours before being served to the panelists. This time allowed the processed chocolate cheese sheets to come off the pans with ease. The cheese was cut into cubes of size 1 cm × 1 cm × 1 cm to fit in 2 oz. Solo white plastic cups (SOLO, P 200, 2 oz., HP 19, Urbana, IL.). The samples were rested for two hours at ambient temperature and were served on Prolon® blue trays at room temperature. Fifty panelists (per each replication) were provided water and expectoration cups and instructed to cleanse the palate between samples.

The samples were assigned three digit random numbers. Samples were rated using a 9-point hedonic scale where 9 is “like extremely” and 1 is “dislike extremely”. Panelists were also asked to rank the samples according to the order of preference where 1st was the most preferred and 4th was the least preferred. The taste tests were held between 10 am and 1 pm daily at the Garrison Sensory Laboratory, Mississippi State University.

There was no time restriction for tasting the samples. No discussion was allowed during the testing.

Statistical Analysis

A randomized complete block design with three replications was utilized to determine the average difference (P<0.05) in consumer acceptability among processed chocolate cheese treatments using SAS (Statistical Analysis Software, version 9.1, SAS“

Institute, Cary, NC). This design with three replications was also utilized to determine

37 differences (P<0.05) among processed chocolate cheese treatments with respect to appearance, flavor, texture and overall liking attributes. When significant differences occurred among treatments, the Least Significant Difference (LSD) test was utilized to separate the treatment means. Processed chocolate cheeses were also analyzed for their overall preferences based on the average treatment means for all the attributes.

Cluster Analysis

Cluster analysis is a multivariate statistical method which groups observations together based on the degree of similarity among their ratings in the same way that PCA groups attributes together based on their degree of correlated behavior (Meilgaard et al.,

1999). An important application of cluster analysis is in sensory acceptance testing where it has been used to identify groups of respondents that have different patterns of liking across products (Meilgaard et al., 1999). Agglomerative Hierarchical Clustering

(AHC) is a cluster analysis algorithm which is used to “make up homogeneous groups of objects (classes) on the basis of their description by a set of variables, or from a matrix describing the similarity or dissimilarity between the objects” (XLSTAT Tutorial, 2007).

In comparison to PCA which has long been used as a stand alone method in sensory and instrumental analyses, AHC is seldom used in sensory studies aside from external preference mapping (Schilling and Coggins, 2007). This method allows a better understanding of the hedonic scaled consumer data by making the results easier to interpret (Ares et al., 2006; Schilling and Coggins, 2007). Another advantage of the AHC is in the graphical presentation of its results using a dendrogram which shows the

38 progressive grouping of the data (XLSTAT Tutorial, 2007). Cluster Analysis was carried out using the XLSTAT 7.5.2 (2006) - Agglomerative Hierarchical Clustering (AHC) for overall liking of the four different processed chocolate cheeses from the consumer panel data. By utilizing table dissimilarity, Eucleadian distance and Ward’s method in the software, a dendrogram and a histogram were obtained. Based on the histogram, 6 clusters of consumers were chosen. A total of 148 consumer panelists’ data was used for the cluster analysis. This was taken from data evaluated by 154 consumer panelists, among whom six consumers did not score and those scores were recognized as missing data. The missing data was not taken into consideration to avoid any conflict that might arise during the analysis of the data.

39 Results and Discussion

Consumer Acceptability

Consumers preferred processed chocolate cheese made with Ghirardelli chocolate the most in terms of its appearance among four different types of processed chocolate cheeses. Processed chocolate cheese prepared with German chocolate was significantly different (P<0.05) among four different types of processed chocolate cheeses with respect to appearance (Table 3.5).

Processed chocolate cheese prepared with Bordeaux chocolate was preferred the most for its flavor attributes among four different processed chocolate cheeses. There were significant differences between processed cheeses made with Dutch and Bordeaux chocolates for flavor, whereas processed cheeses made with Ghirardelli, Dutch and

German chocolates were scored similarly by the consumers with respect to flavor (Table

3.5).

The texture of the processed cheese made with Bordeaux chocolate was the most preferred. There were significant differences (P<0.05) found between processed cheeses made with German and Bordeaux chocolates for texture (Table 3.5).

Processed cheese made with Bordeaux chocolate received the highest score for its overall liking by the consumers. But, there were no significant differences (P>0.05) observed among all the processed cheeses made with chocolates Bordeaux, Ghirardelli,

Dutch and German chocolates for overall liking (Table 3.5).

Overall preferences for all processed chocolate cheeses are in the following order:

Bordeaux, Ghiradelli, German, and Dutch (Fig 3.1).

40 Table 3.5: Overall intensity means for all the processed chocolate cheeses for different parameters evaluated using the consumer panels for acceptability.

Types of processed chocolate cheeses Attributes Bordeaux Ghirardelli Dutch German Appearance 6.8a 7.1a 7.0a 6.3b Flavor 6.7a 6.6ab 6.4b 6.6ab Texture 6.7a 6.6ab 6.6ab 6.2b Overall Liking 6.6a 6.5a 6.4a 6.4a a, b Means within a row not followed by the same letter indicate significant differences (P<0.05). Attributes are scored on a scale of 1 to 9.

Ranking by preferences for processed chocolate cheeses

3

2.95

2.9

2.85

2.8

2.75

2.7 Ranking (Inverse Sum*1000) Sum*1000) (Inverse Ranking

2.65 Bordeaux Dutch German Ghirardelli Types of processed chocolate cheeses Figure 3.1: Graphical representation of ranked overall preferences as given by the consumers for consumer acceptability of processed chocolate cheeses made with different types of cocoa.

41 Cluster Analysis

Clusters 1 through 6 contained 7, 5, 12, 18, 50 and 56 consumers, respectively. By observing the centroid data of each cluster, the following conclusions were drawn:

Cluster 6 comprising 38% of the total consumers moderately liked all of the treatments.

Cluster 5 comprising 34% of the total consumers slightly liked all of the treatments but preferred processed cheese made with Bordeaux chocolate. Cluster 4 comprising 12% of the total consumers slightly liked all of the treatments. Cluster 3 comprising 8% of the total consumers slightly liked processed cheeses made with Bordeaux but preferred the one with Dutch. Cluster 2 comprising 3% of the total consumers didn’t like the processed cheese made with Ghirardelli chocolate. Cluster 1 comprising 5% of the total consumers neither preferred cheese nor chocolate. (Figure 3.2). (Table 3.6).

Table 3.6: Centroid scores on a 9-point hedonic scale for clusters of consumer segments with varying preferences for processed chocolate cheeses.

Cluster Number of consumers Bordeaux Dutch German Ghirardelli Cluster 1 7 1.857 3.286 1.571 1.857 Cluster 2 5 7.000 7.400 6.400 3.000 Cluster 3 12 5.167 7.250 4.833 6.750 Cluster 4 18 4.222 4.722 4.611 4.667 Cluster 5 50 6.980 5.700 6.960 6.720 Cluster 6 56 7.804 7.768 7.482 7.804

42 43

Dendrogram

288

240

192

144

Dissimilarity 96

48

0 3 2 1 2 3 4 5 6

Figure 3.2: Dendrogram for 148 consumers surveyed, truncated at the level of 21 dissimilarity, indicating the six clusters of consumer segmentations for processed chocolate cheese preferences for overall liking. Conclusion

Texture was not found to be significantly different among all three replications (P<0.05). The four treatments were found to be significantly different

(P<0.05), with respect to the attributes of appearance, texture, and flavor. There were no significant differences (P>0.05) among all four treatments with respect to overall liking. (Table 3.5).

Processed chocolate cheese prepared with German chocolate received lower scores from the rest of processed chocolate cheeses, with respect to its appearance.

Texture-wise, processed chocolate cheeses made with German and Bordeaux were significantly different (P<0.05) from the processed chocolate cheeses made with

Ghirardelli and Dutch cocoa. German chocolate was reported as having a gritty texture during the panel. Processed chocolate cheeses made with Dutch cocoa and

Bordeaux chocolate, had a significant difference (P<0.05) in flavor with respect to each other.

Processed chocolate cheese prepared with Bordeaux chocolate was the most preferred of the four treatments by the majority of the consumers with respect to all attributes except appearance. This was followed by processed chocolate cheeses made with Ghirardelli, German and Dutch cocoa, respectively (Figure 3.1).

According to the data, processed chocolate cheese made with Bordeaux had strong chocolate flavor but the texture was smooth and similar to fudge. It had a dry texture and stickiness in the mouth while chewing. Because of its strong chocolate flavor, use of cheese in larger quantities in the formula is advisable. A bitter taste was

44 reported and a more grainy texture was observed. It lacked a brighter appearance affecting its aesthetic quality. Of all the processed chocolate cheeses, this product has the potential to go into the market.

Processed chocolate cheese made with Ghirardelli was also reported having grainy texture but was very well accepted. Texture was very well accepted and it had the best cheese flavor among all processed chocolate cheeses. Like processed chocolate cheese with Bordeaux, it also carried a bitter flavor but in contrast, had brighter appearance enhancing its visual appeal.

Processed cheese with German chocolate also had more grainy and more gritty texture. It had a delicious flavor according to the remarks received on the consumer panel score sheets, but it had the dullest appearance among all. Also it had a salty taste.

Processed cheese with Dutch cocoa had the brightest appearance, possibly due to the nature of the cocoa used. Fat separation was maximum for this treatment during its processing. It had the strongest chocolate flavor of all, and carried the most bitter taste among. It was well preferred by the people who had the tendency to like dark chocolates. Among all of the processed chocolate cheeses, this one had the closest flavor to cheese according to the remarks provided by the consumers on the score sheets.

Given the preliminary nature of the work, further research needs to be carried out in order to evaluate the descriptive sensory attributes of all processed chocolate cheeses to obtain a sensory lexicon, to be used as a guide.

45 CHAPTER IV

PRODUCT FORMULATION AND QUANTITATIVE DESCRIPTIVE

ANALYSIS OF AGED CHEDDAR CHEESE WITH DIFFERENT

TYPES OF CHOCOLATE INCLUSIONS

Abstract

Four Cheddar cheese varieties with different types of chocolate inclusions and a control were evaluated utilizing quantitative descriptive analysis by six trained panelists. Varieties were evaluated for appearance (four), basic taste(s) (five), flavor

(thirteen) and hand evaluated texture (three) attributes. There were no statistical differences (P>0.05) except for those that are most probably a result of the number and type of the chocolate chips per sample. This research will provide the cheese and chocolate industry with a guiding reference tool to develop new and innovative products in the respective sectors in the future and to promote consumer acceptance of a blending of cheese and chocolate.

Key words: Chocolate inclusions, descriptive analysis.

Introduction

The use of quantitative descriptive analysis for the development of a new product such as aged Cheddar cheese with chocolate chips could possibly benefit both

46 the cheese and chocolate industries by providing sensory information in regards to change in either of these products as a result of merging. Quantitative descriptive sensory analysis (QDA®) (Stone, Slidel, Oliver & Woolsey, 1980) is one of the most informative and comprehensive scientific tools that helps greatly in establishing a sensory lexicon or determining sensory attributes. The acceptability of aged Cheddar cheeses with chocolate chips depends on various factors such as its appearance, taste, flavor and several textural attributes. There are several processed cheese products on the market and there is a surge of innumerable innovative chocolate products from time to time. This research primarily focuses upon the incorporation of chocolate into

Cheddar cheese.

Appearance factors included were overall quality appearance, evenness of color (cheese only), distribution of chocolate and cheese and oiliness. The complex nature of the product and its associated flavors were introduced in developing the sensory attributes by understanding the critical phenomenon of moisture migration and chocolate/fat interactions within Cheddar cheese. The different flavor terms that have been identified to study the nature of the product during this research were cheese flavor, cooked flavor, whey, sulfur, earthy, musty/moldy, nutty, fruity, chocolate flavor, alcohol, yeasty, free fatty acid and chlorine. Chlorine flavor was added by the panelists.

Depending upon the nature of the product, it was evaluated for its hand-held textural attributes only, such as springiness, firmness and crumbliness, etc. The texture of a food is often a major determinant of how well a food is liked (Potter &

47 Hotchkiss, 1995). Since texture is a major attribute that influences packaging, additional terms will need to be added to describe the complete nature of the product.

Storage temperatures of this product are not well understood. Further research is needed to comprehend the shelf life and storage conditions of this particular product due to the effect of aging.

The panelists were trained with several rigorous practice sessions for approximately forty five hours over six weeks, to be able to understand the descriptive attributes of this product. This training included the use of references and standardization of sensory perceptions. As this new product might have the possibility of introducing new sensory attributes, the descriptive analysis was restricted to several traditional sensory terms that describe the attributes of Cheddar cheese and chocolate during the training of the panelists.

Preliminary studies suggested that further work needs to be carried out in order to better understand the nature of this product in terms of its appearance, taste, flavor and texture. The nature of the present study provided a general idea to what extent developing a Cheddar cheese with chocolate inclusions needs to be carried out in the future.

48 Materials and Methods

Formulations

Cheddar cheese curd was collected at the time of hooping from Mississippi

State University’s Edward W. Custer dairy plant and mixed with two kinds of chocolate chips, real semi-sweet chips (Nestle’s Toll House) and bittersweet chips

(Ghirardelli). Four treatments and a control consisted of:

1. 15% (wt/wt) of semi-sweet chocolate chips in 85% (wt/wt) of Cheddar cheese curd 2. 20% (wt/wt) of semi-sweet chocolate chips in 80% (wt/wt) of Cheddar cheese curd 3. 15% (wt/wt) of bittersweet chocolate chips in 85% (wt/wt) of Cheddar cheese curd 4. 20% (wt/wt) of bittersweet chocolate chips in 80% (wt/wt) of Cheddar cheese curd 5. 100% Cheddar cheese curd

Process Description

The amounts for the real semi-sweet and bittersweet chocolate chips (15% and

20%) were weighed for each treatment. The weight of the cheese curd was 2.5 lb., including the weight of chocolate chips. A control was chosen from the same batch of the cheese curd for each day without the addition of chips, and each cheese mold

(Kadova, 2.5 lb capacity) was filled to contain 2.5 lb. All personnels’ hands were sanitized with a 200 ppm chlorine solution, then gloved with powder free medium vinyl exam gloves (GS Select, NJ), and a 60.96 cm hairnet (Bouffant, Fisher

Scientific, Pittsburg, PA) was worn by all personnel involved. Care was taken to avoid any external contamination of the samples. Cheese cloths were properly

49 sanitized using 200 ppm Chlorine solution, before being placed into the cheese molds.

The filled cheese mold containers were placed vertically between two stationary pillars and were pressed applying longitudinal pressure from the top by using an air driven mechanical press (Speedaire®, Dayton Electrical Manufacturing Co., Niles,

IL) under a constant pressure of 75 k Pa for 24 hours. On the following day, the samples were taken out of the containers, vacuum packed {Koch Digi-soft Sensor,

BG-Prufzert NG 91169, Gepriifte Sicherheit (GS)}, in 9 cm × 10 cm food grade polythene bags (Cryovac®, Sealed Air Corp., Ayer, MA) followed by shrinking in hot water using a steam generator (General Host Corp., Stamford, CT ) at 121.1°C.

They were stored at refrigeration temperatures of 7°C in the cheese storage room at the Mississippi State dairy plant. Each treatment was replicated three times.

Microbial Analysis of Cheddar Cheeses with Chocolate Chips

Microbial analysis of Cheddar cheese samples was conducted at Bedenbaugh

Laboratory, Mississippi State University to assure microbial quality. Standard

Methods for the Examination of Dairy Products clearly states how to perform the coliform tests on various dairy products (Barber & Fram, 1955). The 10th edition of

Standard Methods for the Examination of Dairy Products defines the coliform organisms as, “All aerobic and facultative anaerobic, Gram-negative, non-spore forming bacteria which ferment lactose with gas formation. Bacteria of both fecal and non-fecal origin are members of the group. In addition to Escherichia and Aerobacter

50 species, it includes a few lactose-fermenting species of other genera.” {American

Public Health Association (APHA), 1953}.

Sampling

Not less than 5 g of each sample was used for the analysis. Care was taken to include both chocolate and cheese when removing the sample from each cheese block.

Apparatus Needed a) Spatula, sterile b) Blender, mechanical (Waring, 1 Liter/1.2 Liter) c) Container for the blender, sterile

All materials used in the blending of the cheese samples were sanitized using a 200-ppm chlorine solution sprayed for 5 minutes and then were rinsed off by a single rinse using 0.1% of aqueous sodium thiosulfate solution (Kraft Chemical

Company, Melrose Park, IL).

Procedure

1) 11 g of each treatment was transferred aseptically to a sterile blender containing

the warmed buffered phosphate solution.

2) Dilution blanks of 99 ml sterile, freshly prepared buffered phosphate dilution

water adjusted pH to 7.2 (34 g KH2PO4 + 500 ml. distilled water) less than 7 days

old, warmed to 40°C, was used.

51 3) The sample was homogenized in the two speed blender for 2 minutes, and the

container was inverted to rinse the particles off the walls of blender and was

remixed for 10 seconds.

4) This created a 1:10 dilution and care was taken to avoid air bubbles.

5) Sample portions containing 1 ml of each sample was plated onto each of 2 plates

of 3MTM petrifilm (St. Paul, MN). The 3M Petrifilm Coliform Count (CC) plate is

a ready made culture medium and it has modified Violet Red Bile (VRB)

nutrients, a cold water-soluble gelling agent and a tetrazolium indicator that

facilitates colony enumeration.

6) Incubation was carried out in a sterile Isotemp incubator (Fisher Scientific®,

Pittsburg, PA) at 35°C + 1°C.

7) Incubation period for total coliform count was 24 hours + 2 hours and for the total

E. coli count 48 hours + 2 hours. E. coli was identified as blue to red-blue

colonies with gas formation. Coliform colonies were red with entrapped gas.

However, regardless of incubation time, whenever a blue colony was associated

with gas formation, it was counted as E. coli and counted in cfu/g.

Panel Preparation (Training)

The treatments were collected from the cheese storage room in the Custer

Dairy Processing Plant at Mississippi State University two hours before each panel and were stored at 5°C in the refrigerator (VikingTM Professional, Model VCSB483) in the Garrison Sensory Laboratory. The Cheddar cheeses with chocolate chip

52 samples were unwrapped, cut into bars of the dimensions 8.75 cm × 5 cm × 3 cm, covered with paper towels, and placed in the cooler (Harford Duracool, Aberdeen,

MD) maintained at 3°C in the Garrison Sensory Laboratory and taken out immediately before the panels. All the samples were labeled with random 3-digit codes.

Panel

Training sessions were carried out for the formal descriptive analysis via round table. All the sliced aged Cheddar cheeses with chocolate chips were placed on

Prolon® red serving trays before each panelist along with a descriptive analysis instrument score sheet, a No. 2 pencil (Dixon Ticonderoga 1388-2/HB Soft), a cup of filtered water (Georgia Mountain Water Inc.), unsalted soda crackers (Premium, Kraft

Foods Global Inc., NJ), and an expectorant cup with snap-on-lid (Sweetheart Cup

Corporation, Owings Mill, MD), and all the references in cups (SOLO, P 200, 2 oz.,

HP 19, Urbana, IL) with lids.

Panelists

Six panelists, two males and four females were trained for a period of approximately 45 hours over a period of 20 days to use Quantitative Descriptive

Analysis (Stone et al., 1980). All the panelists voluntarily participated in this training and were chosen from the department of Food Science, Nutrition and Health

Promotion at Mississippi State University.

53 Panelists’ Training

The degree of complexity of the product necessitated the need to explore the possible flavors present and to determine the sensory attributes that required measuring. Panelists’ training included the assessment of all possible sensory attributes for the aged Cheddar cheeses with chocolate chips. Food and chemical reference standards were used through out the training sessions (Tables 4.1 to 4.4). A

15-point Universal SpectrumTM intensity scale for references was used as sensory descriptive tool, where 0=attribute not detected; and 15=attribute extremely detected.

These attribute categories included appearance, flavor, and hand evaluated texture attributes based on intensity levels. Some of the anchors in the scale were initiated by panelists’ recommendations as they were determined to be product specific, and reference standards also differed from the standard universal scale (See score sheet in

Appendix C).

Testing Area

The testing area had filtered air, positive air pressure and a constant temperature maintained at 21°C through out the panel. All the tests were performed via a round table with ideal ambient conditions, proper lighting and isolated from the area of preparation.

Sample Preparation

Each 2.5 lb block of Cheddar cheese used for panelists’ training was cut into seven blocks that were approximately 8.75 cm × 5 cm × 3 cm in dimension. The

54 blocks of Cheddar cheeses with chocolate chips were collected from the storage area in the dairy plant one hour before and refrigerated immediately after they were cut into the above dimensions, placed on the 10 cm diameter plastic plates (Sweetheart

Cup Company Inc., Chicago, IL) on serving trays and were covered with Bounty paper towels (Procter & Gamble, Cincinnati, OH) to reduce loss of surface moisture.

The approximate serving temperature was 10°C. Plant Cheddar cheese ripened for the same time period of 105 days was placed at ambient temperature 2 hours before the panel for the analysis of the attribute “oiliness”.

The references for the four basic tastes were prepared by using corresponding values on the SpectrumTM Intensity Scale (Meilgaard et al., 1991). Flavor terms and references utilized were obtained from the standards selected to reference terms of

Cheddar flavor language (Murray & Delahunty, 2000a, 2000b) and the Cheddar lexicon (Drake, McIngvale, Gerard, Cadwallader & Civille, 2001). Several reference standards, reference terms and definitions of the sensory attributes were modified from the above listed guides to better describe Cheddar cheeses with chocolate chips.

Several new terms were included depending upon the nature of the new product such as evenness of color (cheese only), distribution of chocolate and cheese, oiliness under the category of overall quality appearance, cheese flavor, musty/moldy, chocolate flavor, alcohol and chlorine (other flavor attributes) under the category of flavor; and the rest remain the same as referenced (Appendix C). The term “age” was intentionally avoided because of its ambiguity. Nutty flavor was closely related with the training samples analyzed for the descriptive analysis. Cowy flavor was found to

55 be an undetectable attribute in the Cheddar cheeses with chocolate chips. Chemical attributes such as pungent and prickle/bite need to be further studied. Texture attributes were evaluated by hand to identify the corresponding characteristics of the

Cheddar cheeses with chocolate chips.

Selection of the Descriptive Terms and Preparation of the Corresponding Standards

All the descriptive terms were generated during the training of the panelists.

The descriptive attributes of Cheddar cheese were taken as a standard reference

(Murray & Delahunty, 2000a, 2000b; Drake et al., 2001). And new terms were generated for new attributes for all the treatments according to the panelists’ recommendations. Total randomization in choosing the samples was practiced and each descriptive panel didn’t exceed four samples on any given panel throughout the five day study period. Cheddar cheeses with chocolate chips were evaluated for appearance, basic taste(s), flavor and texture (only hand evaluated). Tables 4.1 through 4.4 indicate attributes evaluated, preparation of standard and descriptor information (see also for brands Appendix B Table 4.16). During each training session, panelists evaluated the descriptors and standards in order to improve the specificity of the term to describe the product. Care was taken to eliminate the redundant terms and to include the necessary terms through out the training panels.

Some of the reference standards were presented in their normal state, and sometimes a carrier, mostly distilled water (Georgia Mountain Water Inc., Ridge Divide, GA) was added at appropriate levels. Among the standards used for the flavor attributes,

56 Danish Blue cheese (musty/moldy), pineapple juice (fruity), and ethanol (alcohol) each had distilled water as a carrier. Upon the consent of the panelists, a common agreement was reached for the final set of twenty four attributes. Four appearance attributes, five basic taste(s), twelve flavor, and three hand evaluated texture attributes were included (Tables 4.1 to 4.4).

Table 4.1: Appearance attributes of Cheddar cheeses with chocolate chips, as determined by panelists.

Attribute Descriptor Overall Quality Appearance Overall quality appearance as determined by trained panelist.

Evenness of Color (Cheese Only) The degree of color leaching from chocolate chips to Cheddar cheese.

Distribution of Chocolate and The uniformity of chocolates chips in Cheddar cheeses sample cheese provided to the panelist.

Oiliness The degree to which the excess amount of oil is perceived on the skin.

Table 4.2: Basic taste attributes for Cheddar cheeses with chocolate chips, as determined by panelists.

Attribute Descriptor Intensity Level Reference Bitter The taste on tongue simulated by 2, 5, 10 Caffeine (Bell Aromatics substances such as caffeine. Caffeine USP anhydrous)

Salty The taste on tongue simulated by 2.5, 5, 8.5 Sodium chloride (Morton sodium salts. Iodide Salt)

Sweet The taste on tongue simulated by 2, 5, 10 Sucrose (Domino, sucrose. granulated)

Sour The taste on tongue simulated by 2, 5, 10 Citric acid (ADM, USP, acids. FCC(U) Anhydrous fine granulated) Umami Referred to as a savory taste. 1.5, 3, 6 MSG (Accent Flavor Enhancer)

Source: Sensory Evaluation Techniques Civille and Lyon 1996. 57 Table 4.3: Flavor attributes for Cheddar cheeses with chocolate chips, as determined by panelists.

Attribute Reference 0-15 Flavor Descriptor Cheese Flavor Vermont cheese 12.0 2 cm cubes Cooked Evaporated Milk 9.0 1 oz. Velveeta 12.0 2 cm cubes Whey Fresh Cheddar whey 7.0 1 oz.

Sulfur New York Cracker 10.0 2 cm cubes Barrel cheese Earthy Mushrooms (raw- 4.5 ½ slice sliced) Musty/Moldy Danish Blue Cheese* 1.0 (0.1%), 4 (0.4%), 8 1 oz. (4%) 1 oz. Brie 4.0 Nutty Roasted Unsalted 5.0 2 halves Almonds Fruity Pineaple Juice* 1.0 (1%), 7 (10%) 1 oz. Chocolate Flavor Baker’s German Sweet 5.5 1 oz. Nestle’s Semisweet 7.0 1 oz. Ghirardelli Bittersweet 8.5 1 oz. Hershey’s Special Dark 8.5 1 oz. Cocoa powder Baker’s German 12.5 1 oz. Unsweetened Alcohol Ethanol* 1.0 (1%), 4 (3%) 1 oz.

Yeasty Yeast Roll 4.0 1 oz.

Free Fatty Acid Feta cheese 10.0 2 cm cubes

* All these samples were diluted with different volumes of water to attain the different degrees of intensity for the same attribute.

58 Table 4.4: Texture attributes (hand evaluated) for Cheddar cheeses with chocolate chips, as determined by panelists.

Attribute Descriptor Reference Intensity level Springiness The degree to which the sample deforms under Large erasers 15 stress, but returns to its original shape when stress is removed

Crumbliness The degree to which the sample fractures rather Feta cheese 13 than Deforms during the course of working the sample in the hand for 3 to 6 times

Firmness The force required to compress between thumb Cool Whip 0 and index finger Jumbo 2 Marshmallow 15 Dry cork of wine bottle

Statistical Analysis

The five treatments were evaluated in an unbalanced, incomplete block design since a block did not have all the treatments. Due to the logistics and the intensity of labor in examining all treatments on any given day, evaluations were limited to no more than four treatments for each of the five panels. Not all treatments were compared with all other treatments in a single panel or equal number of times.

Random effects included variation between the two replicates over time and differences among panels, which statistically are blocks and differences among panelists. Proc Mixed Analysis (SAS®, 2003) was utilized for these results with unequal variances which facilitated adjustment of the variance/covariance matrix of random effects.

59 Principal Component Analysis (PCA)

Principal Components Analysis (PCA) is a statistical analysis technique used “to identify the smallest number of latent variables, called “principal components”, that explain the greatest amount of observed variability” (Meilgaard et al., 1999).

According to Dunteman (1989), the goal of this multivariate data analysis method is to reduce the dimensionality of the original data set since a small set of uncorrelated variables is easier to grasp and utilize in further analysis compared with a larger set of correlated variables. This method is responsible for explaining 75% to 90% of the total variability through two to three principal components by using a data set with 25 to 30 variables. PCA biplots help in understanding a notable portion of the total variation through clustering of the attributes into two or three principal components.

The PCA biplot represents variables and data graphically. However, these representations can only be reliable if the “sum of the variability percentages associated with the axes of the representation space are sufficiently high (i.e. 80%)”

(XLSTAT Tutorial, 2007).

60 Results and Discussion

Microbial Analysis

Of the of 39 total plates (1 to 39) evaluated for coliform counts, the counts on all of them were <10 cfu/g, except for plates 15, 16, 19 and 20 which were reported to have an estimated 10 cfu/g. The plates were stored at ”15°C in a sterile isotherm incubator for later enumeration of the samples, but no longer than a week. No plate exceeded the safe limit of 100 cfu/g {American Public Health Association (APHA),

1953}.

Quantitative Descriptive Analysis

Descriptive Analysis: Appearance

Differences in appearance (P<0.05) were found among the four different

Cheddar cheeses with chocolate chips including the control sample (Table 4.5). This is due to the apparent visual differences of the treatments themselves. Regardless of how the treatments were sliced and prepared for presentation to panelist, each panelists’ sample was somewhat different in appearance.

There were no significant differences (P>0.05) in overall quality appearance found among the Cheddar cheeses with chocolate chips which was based on evaluations of the treatments. Quality of appearance was rated on the same intensity scale, 0-15, with 0 being extremely unacceptable quality and 15 being extremely high quality. All of the treatments were cut into individual samples and rated on the visual appearance of each. This measurement was subjective as each panelists’ sample was

61 visually different. The control was significantly different (P<0.05) from all the other treatments except from Cheddar cheese with 15% bittersweet chocolate chips. It can be attributed to the reason that not many bitter chocolate chips were available in the sample provided to the panelist affecting its overall quality appearance (Table 4.5).

Evenness of the color (cheese only) was not different (P>0.05) among all

Cheddar cheese treatments with chocolate chips. The control was different (P<0.05) from all the other treatments. Color varied due to distribution of chocolate within the cheese. This can be viewed subjectively as each panelist had a different view of the treatments (Table 4.5).

There were no differences (P>0.05) among all Cheddar cheeses with chocolate chips with respect to distribution of Chocolate and Cheese. The control was different (P<0.05) from all the other treatments. All the cheese treatments had an adequate distribution of chocolate thoughout the cheese. The control would of course be different as it had no chocolate chips (Table 4.5).

The treatment of Cheddar cheese containing 15% semi-sweet chocolate chips was significantly different from all the other treatments, including the control. The oil observed was a result of the cheese, not the chocolate inclusion (Table 4.5).

62 Table 4.5: Descriptive appearance attribute intensity means for the Cheddar cheeses with chocolate chips and control as determined by a trained panel (n=6).

Appearance Semi- Semi- Bittersweet- Bittersweet- Control Attributes sweet- sweet- 15% 20% 15% 20% Overall Quality 7.8b 5.9b 7.9ab 7.2b 9.9a Appearance Evenness of Color 6.7b 5.3b 7.1b 6.7b 10.7a (Cheese Only)

Distribution of 8.0a 6.4a 8.4a 8.5a 1.5b Chocolate and Cheese

Oiliness 0.2b 0.9a 0.7a 0.5a 1.0a

a, b Means within a row not followed by the same letter are significantly different (P<0.05). Attributes are scored on a scale of 1 to 15.

Descriptive Analysis: Basic Taste(s)

There were differences (P<0.05) observed in basic tastes among treatments.

Cheddar cheeses with 15% and 20% bittersweet chocolate chips were different

(P<0.05) from Cheddar cheeses with 15% and 20% semi-sweet chocolate chips for bitter basic taste attribute. This is due to the type of chocolate inclusion; bittersweet is more bitter than semi-sweet. The control was different (P<0.05) from Cheddar cheese with 15% of semi-sweet chocolate chips with respect to bitter taste. This could be a result of the inclusion of the chocolate making the treatments less bitter or simply the fact that all cheeses from all particular regions regardless of the type of cheese will vary due to inherent differences stemming from bacteria, milk, processing or other variables (Table 4.6). There were no differences (P>0.05) observed among all the treatments with respect to salty (Table 4.6).

63 There were differences (P<0.05) observed among Cheddar cheeses with chocolate chips with respect to sweet. It was due to the basic differences between the types of chocolate chips such as bittersweet and semi-sweet. Control was less sweet

(P<0.05) than all the other treatments. Cheddar cheeses with 15 % and 20 % semi- sweet chocolate chips were sweeter (P<0.05) than the Cheddar cheese with 15 % and

20 % bittersweet chocolate chips. The difference in sweetness could be a result of the chocolate inclusions (Table 4.6).

There were no differences (P>0.05) observed among all Cheddar cheeses with chocolate chips with respect to sour. The control was more sour (P<0.05) than all the other treatments. The inclusion of chocolate could have an impact on the sourness attribute (Table 4.6).

There were no differences (P>0.05) observed among all treatments with respect to umami. Umami would not be a basic taste observed in the product at high intensities. The cheese with chocolate inclusions were much more sweet than savory.

Umami is highly attributed to savory foods (Table 4.6).

64 Table 4.6: Descriptive basic taste attribute intensity means for the Cheddar cheeses with chocolate chips and control as determined by a trained panel (n=6).

Basic Semi-sweet- Semi-sweet- Bittersweet- Bittersweet- Control Taste 15% 20% 15% 20% Attributes Bitter 1.4c 1.8bc 3.0a 3.1a 2.4ab Salty 1.0a 1.3a 1.2a 1.2a 2.0a Sweet 2.7ab 3.4a 1.4c 1.8c 0.7d Sour 1.0b 0.9b 1.5b 1.2b 2.4a Umami 0.7a 0.8a 0.8a 0.7a 1.4a a, b, c, d Means within a row not followed by the same letter are significantly different (P<0.05). All attributes are scored on a scale of 1 to 15.

Descriptive Analysis: Flavor

There were no differences (P>0.05) observed among Cheddar cheeses with chocolate chips with respect to cheese flavor. The control was significantly higher

(P<0.05) in cheese flavor than all the other treatments. This was apparent as it had no chocolate inclusions. Based on the obtained means, it can be determined that the

Cheddar cheeses made with bittersweet chocolate inclusions rated lower on the intensity of cheese flavor. This is probably due to the fact that the bittersweet inclusions allowed more of the natural Cheddar flavor to come through as it was not masked by sweetness as in the Cheddar cheese with semi-sweet inclusions (Table

4.7).

There were no differences (P>0.05) among all treatments for cooked flavor.

Cooked flavor, as it is associated with warm flavors resulting from cooking, was not altered. It could have been due to the aging, during which the cooked flavor had been masked (Table 4.7).

65 There were no differences (P>0.05) observed among all Cheddar cheeses with chocolate chips with respect to whey flavor. The control was higher (P<0.05) in whey flavor than all the other treatments. The inclusion of chocolate chips in Cheddar cheeses might have altered the whey flavor that was perceived (Table 4.7).

There were differences (P<0.05) between Cheddar cheeses with 15% bittersweet chocolate chips from 15% and 20% semisweet chocolate chips with respect to sulfur flavor. The control was higher (P<0.05) in sulfur flavor than all the other treatments. Cheddar cheese can be characterized by its sulfur content and it could have been masked by the addition of chocolate chips (Table 4.7).

There were significant differences (P<0.05) for earthy flavor between Cheddar cheeses with 15% semisweet chocolate chips and Cheddar cheeses with 20% bittersweet chocolate chips. Chocolate can be characterized by its earthy flavors. As shown by the mean values, the more chocolate chips, the higher score in earthy flavor. Lower mean values of treatments with semi-sweet chocolate chips could suggest the ability of sweetness to suppress earthy flavors (Table 4.7).

There were differences (P<0.05) found between Cheddar cheeses with 15% semi-sweet chocolate chips and Cheddar cheeses with 15% and 20% bittersweet chocolate chips with respect to musty/moldy flavor. Chocolates have been noted for their alcohol flavor which is closely associated with musty/moldy flavor (Table 4.7).

There were no differences (P>0.05) found among all treatments with respect to nutty flavor. The factors such as type of chocolate chips, amount of chocolate chips, and aging time periods did not alter the perception of nutty flavor (Table 4.7).

66 There were no differences (P>0.05) among all treatments for fruity flavor.

More research needs to be done in this area to analyze for this attribute in these types of cheeses (Table 4.7).

There were no differences (P>0.05) among all Cheddar cheeses with chocolate chips in chocolate flavor. The control was lower (P<0.05) in chocolate flavor than all the other treatments except Cheddar cheese with 15% bittersweet chocolate chips. The size of the chocolate chips included in Cheddar cheeses and their corresponding amounts mattered in perceiving chocolate flavor. The statistical differences noted above may be attributed to the fact that the samples received by the panelists might have had more or less chips in them (Table 4.7).

There were no differences (P>0.05) found among all treatments with respect to alcohol flavor. This was a desirable finding since alcohol is not a flavor that should be found in these products (Table 4.7).

There were no differences (P>0.05) found among treatments with respect to yeasty flavor. This attribute was not widely noted (Table 4.7).

There were no differences (P>0.05) found among all Cheddar cheeses with chocolate chips with respect to free fatty acid flavor. There were differences (P<0.05) between the control and Cheddar cheeses with 15% and 20% of semi-sweet chocolate chips. This could be a result of the chocolate inclusions themselves adding a positive flavor note (Table 4.7).

There were no differences (P>0.05) observed among all Cheddar cheeses with chocolate chips with respect to chlorine flavor. There were differences (P<0.05)

67 between the control and Cheddar cheese with 20% of semi-sweet chocolate chips.

Chlorine is not a flavor attribute of the research cheeses per se, however it was a term the panelists could identify that was meaningful in word only (Table 4.7).

Table 4.7: Descriptive flavor attribute intensity means for the Cheddar cheeses with chocolate chips and control, as determined by a trained panel (n=6).

Flavor Semi-sweet- Semi-sweet- Bittersweet- Bittersweet- Control Attributes 15% 20% 15% 20% Cheese Flavor 2.3b 2.5b 3.3b 3.0b 5.9a Cooked 2.7a 3.1a 2.7a 2.3a 2.8a Whey 1.1b 1.0b 1.0b 0.8b 1.8a Sulfur 0.2b 0.2b 0.8c 0.4bc 1.6a Earthy 0.8b 1.0ab 1.3ab 1.5a 1.4ab Musty/Moldy 0.5b 0.8ab 1.4a 1.1a 1.1ab Nutty 1.8a 1.8a 2.1a 1.9a 1.3a Fruity 0.6a 1.0a 1.0a 0.6a 0.8a Chocolate 3.8a 4.3a 3.7ab 5.3a 1.4b Flavor Alcohol 0.9a 0.8a 1.9a 1.0a 0.5a Yeasty 0.5a 0.5a 0.7a 0.5a 0.4a Free Fatty 0.2b 0.2b 0.4ab 0.3ab 0.5a Acid Other 1.7ab 0.8b 1.6ab 1.0ab 3.0a (chlorine) a, b Means within a row not followed by the same letter are significantly different (P<0.05). All attributes are scored on a scale of 1 to 15.

Descriptive Analysis: Texture

There were differences (P<0.05) observed between Cheddar cheeses with 15% bittersweet chocolate chips from Cheddar cheeses with 15% and 20% semi-sweet chocolate chips with respect to springiness. The control had more springiness

(P<0.05) than all the other treatments except Cheddar cheeses with 15% bittersweet chocolate chips. The different types of chocolate inclusions could have attributed to this difference in springiness (Table 4.8).

68 Differences (P<0.05) were found between Cheddar cheeses with 15% bittersweet chocolate chips and Cheddar cheeses with 20% semi-sweet chocolate chips with respect to crumbliness. The control was more crumbly (P<0.05) than all the other treatments except Cheddar cheese with 15% bittersweet chocolate chips.

Again, this could be attributed to the chocolate inclusions and the differences in the area of distribution of the inclusions (Table 4.8).

There were no differences (P>0.05) among Cheddar cheeses with chocolate chips with respect to firmness. The control was less firm (P<0.05) than all the other treatments. This is likely due to no chocolate inclusions (Table 4.8).

Table 4.8: Descriptive texture attribute intensity means for the Cheddar cheeses with chocolate chips and control as determined by a trained panel (n=6).

Texture Semi-sweet- Semi-sweet- Bittersweet- Bittersweet- Control Attributes 15 % 20 % 15 % 20 % Springiness 4.0c 4.3c 7.5ab 5.3bc 9.7a Crumbliness 9.2ab 9.5a 7.1bc 8.3ab 5.4c Firmness 11.7a 11.5a 10.3a 11.2a 7.0b a, b, c Means within a row not followed by the same letter are significantly different (P<0.05). All attributes are scored on a scale of 1 to 15.

Interpretation of Interaction Plots between Panelist & Treatment

A total of 14 descriptive attributes were evaluated to test the panelist versus treatment interactions for the Cheddar cheeses with chocolate chips, among which distribution of chocolate and cheese, evenness of color, bitter, salty, sweet, sour, umami, cheese flavor, cooked, sulfur, nutty, chocolate flavor, springiness, crumbliness and firmness were present. These terms were selected and considered as

69 key terms in view of their degree of importance in deciding the critical nature of the new product.

The range indicates large variation, but the trend followed by the panelists in the evaluation of distribution of chocolate and cheese in the Cheddar cheeses with chocolate chips was similar. This was attributed to the fact that the samples received by the panelists were different and some of them had more distribution of chocolate chips where some of them might not have any chips visible on the cut surface (Figure

4.2).

Differences in Cheddar cheeses with chocolate chips explain the reason why there was no clear trend between the panelist and the treatment with respect to evenness of color. The four different treatments and one control, all being different, would be self explanatory for this kind of interaction (Figure 4.3).

There was a large variation in the range of intensity values for bitter, though there is a clear trend observed for the treatment as for as the panelist is concerned.

Bitterness is a basic taste attribute which is perceived differently by each individual.

Degree of perception would change how the panelists reacted to the bitterness. Some of the individuals are super tasters of this attribute, some of them are medium tasters, and some of them are not sensitive to this attribute at all (Figure 4.4).

A clear trend was observed for salty with the range between the intensity values being very small, it was concluded that all the treatments were treated by the panelists in a similar fashion (Figure 4.5).

70 The data for sour followed the same trend by all the panelists as that of the basic attribute “salty”. A clear trend was observed, though there was a moderate variation between the range values of the intensity. There was an interaction with variation and it was better explained by the variance in the degree of perception of the basic taste “Sour” among panelists (Figure 4.7).

Though a clear trend was observed for umami, there was an occurrence of outliers. It could have been due to the lack of clear understanding of how to perceive this particular attribute. It was concluded that more training may have been needed for this flavor attribute (Figure 4.8).

The data for cheese flavor followed a very clear trend. There was an interaction observed for each of the panelists. Since the samples received were the same for each and every panelist, there were very few differences found in the perception of the cheese flavor (Figure 4.9).

The data for cooked flavor showed that it followed a clear trend with interactions. Some variations in the differences among the intensities that existed were better explained by the type of cheese that was being consumed by each of the panelists. If more chocolate chips existed in the portion of the cheese taken in the mouth, then it would affect the perception of the cooked flavor (Figure 4.10).

There was a very clear trend observed in the amount of sulfur found in each treatment and as it was well perceived by each of the panelists. All the controls, had more sulfur content than the samples which contained chocolate chips. There was a

71 possibility that the chocolate content in Cheddar cheese might have reduced the ability of the panelist to perceive the sulfur flavor (Figure 4.11).

According to the scores (Figure 4.12), panelists could be divided into two groups with one group scoring the cheeses high for “Nutty” flavor and the other group scoring it low. Some panelists may not have understood how to identify nutty flavor in some samples (Figure 4.12).

Chocolate flavor is a very important term in view of this research. It again depends on how many of the chocolate chips were being consumed by the different panelists. It had a very clear trend. The panelists understood the term “Chocolate

Flavor” and displayed similar perception of all the samples (Figure 4.13).

An inverse trend was observed in the case of firmness compared to the characteristics of the interaction plot of crumbliness attribute. It was due to the presence of the chocolate chips in the sample making the cheese seem more crumbly as it was held by the panelist to work between their fingers (Figure 4.14).

Though there was a large variation in the range of intensity values, a clear trend has been shown with respect to crumbliness. The large variation was explained according to the nature of the sample received by the each panelist, such as one sample might have more chocolate chips and some had none or not as many. As the presence of the chips influences the fracturability, it in turn affects the degree of perception of the term “Crumbliness” (Figure 4.15).

Though there was some degree of variation in the range of intensities, a very clear trend was observed in the case of springiness (Figure 4.16).

72 Significance of Panelist * Treatment Interactions

A panel which consisted of 4 females and 2 males analyzed the four different types of Cheddar cheeses with chocolate chips ripened for 105 days, including a control. There was a difference (P<0.5) among the panelists in scoring several attributes of all the treatments. However, there was no statistical significance

(P>0.05) found among the panelists towards an attribute such as sulfur in all the samples.

Interactions are very important in the descriptive panels, as they provide the necessary insights into understanding the relationship between the panelist and the treatment when looking for a certain attribute in the sample. There was a difference

(P<0.05) among the panelists versus treatment interactions in analyzing the attributes; bitter, sweet, cooked, free fatty acid and chocolate flavor. There was no difference

(P>0.05) found among the panelists versus treatment interactions in analyzing for attributes; overall quality appearance, evenness of color, distribution of chocolates and cheese, oiliness, salty, sour, umami, cheese flavor, whey, sulfur, earthy, musty/moldy, nutty, fruity, alcohol, yeasty, chlorine, springiness, crumbliness and firmness.

Principal Component Analysis

The first eigen vector accounted for about 75% of the variation. An inspection of the vector (Table 4.9) indicates bitterness was not a substantial component and that near equal weighting of the responses for overall quality appearance, evenness of

73 color, sour, cheese flavor, sulfur flavor and chlorine flavor were contrasted with sweet, nutty, chocolate flavor, crumbliness, and firmness. The second eigen vector accounting for nearly 14% of the variation was heavily weighted by the bitter factor and included near equal weightings of nutty and chocolate flavor contrasted with sweet and chlorine flavor. The other factors had little influence in this vector. Thus the biplot of the first two components addresses nearly 89% of the variation. The principal component analysis biplot for all the attributes (Figure 4.1) reveals that all of the treatments can be better differentiated by stronger nutty, chocolate and chlorine flavors. The control can be better described in terms of its overall quality appearance, evenness of color, sourness, cheese flavor, sulfur flavor and chlorine flavor. Also,

Cheddar cheeses with 15% and 20% of bitter chocolate chips could be well differentiated from the other treatments as they had evenness of color, sourness, cheese flavor, sulfur flavor, nutty flavor, chocolate flavor and chlorine flavor. The

Cheddar cheeses with 15% and 20% of semi-sweet chocolate chips can be well differentiated from the other treatments with respect to sweetness, crumbliness and firmness.

74 Table 4.9: Eigen component factors that account for 89% of the total variation in principal component analysis of different attributes of different treatments.

Attribute Eigen factor 1 (75%) Eigen factor 2 (14%) Overall quality appearance 0.30 -0.03 Evenness of color 0.32 0.02 Bitter 0.08 0.74 Sweet -0.28 -0.28 Sour 0.31 0.16 Cheese flavor 0.32 0.07 Sulfur flavor 0.31 0.08 Nutty flavor -0.25 0.35 Chocolate flavor -0.30 0.30 Chlorine flavor 0.25 -0.33 Crumbliness -0.31 -0.07 Firmness -0.33 -0.0002

75 (14%)

(75%) Figure 4.1: Principal component biplot of descriptive analysis for all the significant (P<0.05) attributes of different varieties of Cheddar cheeses with chocolate chips.

76 Correlation Matrix

The degree of correlation between the terms used to describe different treatments can be explained by the correlation matrix (Table 4.10). At correlation r=0.754, any two given attributes were significantly correlated (P<0.05). Among 25 attributes evaluated, 19 attributes showed significant correlation with one or more than one attribute. Six attributes namely, sulfur, earthy, fruity, yeasty, free fatty acid and crumbliness had shown no significant relationship (P>0.05) to any of other attributes.

Among appearance attributes, overall quality appearance, evenness of color

(cheese only), and distribution of chocolate and cheese were strongly correlated with each other. From a new product stand point, overall quality appearance is a reflection of all these attributes. Further, overall quality appearance was also significantly correlated with cheese flavor, as likeliness towards a particular cheese is always influenced by the factor of aging. Oiliness was also strongly correlated with the texture attribute “springiness”. If the cheese is oily, then it is not springy and vice versa.

Among basic tastes, bitter was strongly correlated with chlorine flavor. Both of them were undesirable in cheeses. Basic taste attribute sweet was correlated with cheese flavor. Normally, sweetness in Cheddar cheese is not very common. But, the inclusion of semi-sweet chocolate chips might have changed the phenomenon. It can be attributed to the fact that differences in taste receptors to perceive these basic tastes might be different and there was no clear distinction exercised by the panelists in

77 treating these attributes. Umami was correlated with whey flavor as it had a very bland and prickle taste. Whey expulsion might be a factor to induce a metal-like taste in it.

Among the flavor attributes, cooked and nutty were strongly correlated as both of them were related to warm flavors and required heat to be formed.

Musty/moldy was correlated with alcohol flavor, and both of these were undesirable.

Musty/moldy was also related with firmness as this flavor can influence the texture of the treatment. Chocolate flavor was also correlated with firmness, as the portions of the chocolate in the treatment were increased, crumbliness increased thus affecting firmness.

78 79

Correlation matrix

Table 4.10: Correlation matrix for significantly correlated (P<0.05) descriptive attributes (at correlation r=0.754) used to profile different varieties of Cheddar cheeses with chocolate chips.

Overall Quality AppearanceEvenness of Color (Cheese only) Bitter Sweet Sour Cheese Flavor Sulfur ) Nutty Crumbliness Chocolate Firmness Flavor Other (Chlorine Overall Quality Appearance 10.861 -0.393-0.775 -0.476 -0.89 -0.018 -0.515 -0.449-0.164 -0.754 -0.696 Evenness of Color (Cheese only) 1 -0.483 -0.584 -0.01 -0.666 -0.091 -0.733-0.251 -0.475 -0.661 -0.574 Bitter 10.762 0.041 0.635 0.25 -0.14 0.881 0.492 0.364 0.357 Sweet 1 0.518 0.927 -0.068 -0.028 0.6560.509 0.596 0.751 Sour 1 0.605 0.044 -0.157 0.0363-0.003 0.149 0.233 Cheese Flavor 1 0.175 0.1 0.3920.489 0.756 0.612 Sulfur 1 -0.046 -0.676 -0.282 0.192 -0.633 Nutty 1 0.193 0.236 0.184 0..229 Chocolate Flavor 1 0.63 0.1530.881 Other (Chlorine) 1 0.333 -0.063 Crumbliness 1 0.512 Firmness 1 * Numbers in bold represent significant correlations (P<0.05). Conclusion

Difficulties arose with panel descriptions due in a large part to the inconsistency of the number of the chips in each sample. Since samples were not prepared using typical manufacturing processes; this inconsistency could be minimized in a commercial product. It is likely that an even mix of curd and chips could be achieved with mechanical mixing. However, the majority of the attributes did not seem to be affected by this inconsistent distribution of chips. Panelists’ differences with bitter, sweet, cooked, free fatty acid and chocolate flavor could be traced to the amount of chocolate in the sample.

Moisture migration, depending on where the sample was cut, could also be a mitigating factor to influence the results. The differences and similarities are expressed in the principal component analysis (Figure: 4.1). The significant relationships between the attributes are shown in the correlation matrix (Table 4.9).

80 CHAPTER V

SUMMARY, IMPLICATIONS AND CONCLUSIONS

Based on this research, the cheese and chocolate industries could create a line of new products by combining the different varieties of chocolates and cheeses. This research would serve as a basic platform for further research to include the incorporation of different chocolate chips to create a more palatable and valuable product. More descriptive analysis research needs to be conducted for development of a complete lexicon on Cheddar cheeses with chocolate chips, if this research proves beneficial to the industry.

The drive to provide variety and better nutrition to enhance calcium intake of consumers is one of the interesting aspects of this research. This form of usage for both of these products still needs to be explored in repetition and more in-depth.

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92 APPENDIX A

INTERACTION PLOTS AND COMPARISON AMONG DIFFERENT TYPES OF

CHEDDAR CHEESES WITH CHOCOLATE CHIPS FOR THEIR

DESCRIPTIVELY ANALYZED ATTRIBUTES

93 94

mD ischch 14 13 12 11 10 9 8 Distribution of Chocolate and Cheese 7

6BS15 BS20 SS15 SS20 c ont r ol Type 5 Panel i st 77 301 363 458 993 8300 4 Fig 4.2: Interaction among the panelists for “distribution of chocolate and cheese” attribute among different varieties of Cheddar3 cheeses with chocolate chips. 2 1 0 95

MEvencol 13

12

11

10

Evenness of Color 9

8

7

6 77 301 363 458 993 8300

Fig 4.3: Interaction5 among the panelists for “evenness of color (cheese only)” attribute among different varieties of Cheddar cheeses with chocolate chips.

4

3 BS15 BS20 SS15 SS20 c ont r ol Type Panel i st 96

mBitter 5

4

Bitter Bitter 3

2

77 301 363 458 993 8300 1 Fig 4.4: Interaction among the panelists for basic taste “bitter” among different varieties of Cheddar cheeses with chocolate chips.

0 BS15 BS20 SS15 SS20 c ont r ol Type Panel i st 97 m a y t Sal i .: Interactionamongthepanelists forbasictaste“salty”among different varietiesofCheddarcheeseswith Fig 4.5: Salty 0 1 2 3 BS15 chocolate chips. Panel i BS20 st 458 77 SS15 Type 301 993 SS20 8300 363 ont c ol r 98

mSw eet 5

4 Sweet

3

BS15 BS20 SS15 SS20 c ont r ol 2 Type Panel i st 77 301 363 458 993 8300 Fig 4.6: Interaction among the panelists for basic taste “sweet” among different varieties of Cheddar cheeses with chocolate chips. 1

0 99

m Sou r 5

r 4 Sou

3

BS15 BS20 SS15 SS20 c ont r ol Type Panel i st 77 301 363 2 458 993 8300

Fig 4.7: Interaction among the panelists for basic taste “sour” among different varieties of Cheddar cheeses with chocolate chips.

1

0 3 100

2

mUm am i

1 Umami

0 BS15 BS20 SS15 SS20 c ont r ol Type Panel i st 77 301 363 458 993 8300

Fig 4.8: Interaction among the panelists for basic taste “umami” among different varieties of Cheddar cheeses with chocolate chips. 101

mC hFl v 8

7

6

Cheese flavor Cheese flavor 3 5

2 4 301 363 1 458 993 8300 BS15 BS20 SS15 SS20 c ont r ol Fig 4.9: Interaction among the panelists for “cheese flavor”Type attribute among different varieties of Cheddar cheeses with chocolate chips.Panel i st 77 102

mC ooked 5

4

3 cooked flavor

2

77 301 363 458 993 8300

Fig 4.10: 1Interaction among the panelists for “cooked flavor” attribute among different varieties of Cheddar cheeses with chocolate chips.

0 BS15 BS20 SS15 SS20 c ont r ol Type Panel i st 103

mSul f ur 3 Sulfur flavor 2

BS15 BS20 SS15 SS20 c ont r ol Type Panel i st 77 301 363 458 993 8300 1 Fig 4.11: Interaction among the panelists for “sulfur flavor” attribute among different varieties of Cheddar cheeses with chocolate chips.

0 4 104 3

mN ut t y 2

1 Nutty flavor

0 BS15 BS20 SS15 SS20 c ont r ol Type Panel i st 77 301 363 458 993 8300 Fig 4.12: Interaction among the panelists for “nutty flavor” attribute among different varieties of Cheddar cheeses with chocolate chips. 105 Fig 4.13:Interaction amongthepanelists for“chocolate flavor” attributeamong differentvarieties ofCheddarcheeses with chocolate chips. Chocolate flavor 106

mFi r m 14

13

12 Firmness 11

10 9

8 301 363 458 993 8300

Fig 4.14:7 Interaction among the panelists for texture attribute “firmness” among different varieties of Cheddar cheeses with chocolate chips. 6

5 BS15 BS20 SS15 SS20 c ont r ol Type Panel i st 77 107

mC rum bl 12

11

10 9

Crumbliness 8

7

6

5 77 301 363 458 993 8300 4 Fig 4.15: Interaction among the panelists for texture attribute “crumbliness” among different varieties of Cheddar cheeses 3with chocolate chips.

2

1 BS15 BS20 SS15 SS20 c ont r ol Type Panel i st 108

mSpr i ng 14

13

12

11

Springiness 10 9

8

7 BS15 BS20 SS15 SS20 c ont r ol 6 Type Panel i st 77 301 363 5 458 993 8300

Fig 4.16: 4Interaction among the panelists for texture attribute “springiness” among different varieties of Cheddar cheeses with chocolate chips. 3

2

1 9.00

8.00

7.00

6.00

5.00 SS

Mean Values BS 4.00

3.00

2.00

1.00

0.00 Overall Quality Evenness of Color Distribution of Oiliness Appearance (Cheese Only) Chocolate and Cheese Appearance Attributes

Figure 4.17: Graphical representation of descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet (SS) and bittersweet (BS) chocolate chips.

Overall Quality Appearance 10.00 8.00 6.00

4.00 SS 2.00 BS Evenness of Color (Cheese Oiliness 0.00 Only)

Distribution of Chocolate and Cheese

Figure 4.18: Spider plot for descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet and bittersweet chocolate chips. 109 4.00

3.50

3.00

2.50 SS 2.00 BS Mean Value 1.50

1.00

0.50

0.00 Bitter Salty Sweet Sour Umami Basic Taste

Figure 4.19: Graphical representation of descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet and bittersweet chocolate chips.

Bitter 3.50 3.00 2.50 2.00 1.50 SS Umami 1.00 Salty BS 0.50 0.00

Sour Sweet

Figure 4.20: Spider plot for descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet and bittersweet chocolate chips.

110 6.00

5.00

4.00

SS 3.00 BS Mean Value 2.00

1.00

0.00

r d y y y y r l y d ) e ey ur th d it o ho ne k lf r ol u av o aci i oo Wh Su Ea Nutt Fr c y or C /M e fl Yeast hl ty Al c s r( u colat Cheese flavo M Free fatt Cho Othe Flavor Attribute

Figure 4.21: Graphical representation of descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet and bittersweet chocolate chips.

Cheese flavor 5.00 Other(chlorine) Cooked 4.00

Free fatty acid 3.00 Whey

2.00

1.00 SS Yeasty Sulfur BS 0.00

Alcohol Earthy

Chocolate flavor Musty/Moldy

Fruity Nutty

Figure 4.22: Spider plot for descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet and bittersweet chocolate chips. 111 14.00

12.00

10.00

8.00 SS BS 6.00 Mean Value

4.00

2.00

0.00 Springiness Crumbliness Firmness Texture Attribute

Figure 4.23: Graphical representation of descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet and bittersweet chocolate chips.

Springiness 12.00 10.00 8.00 6.00

4.00 SS 2.00 BS 0.00

Firmness Crumbliness

Figure 4.24: Spider plot for descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet and bittersweet chocolate chips.

112 9.00

8.00

7.00

6.00

5.00 SS-20% BS-20% 4.00 Mean Value 3.00

2.00

1.00

0.00 Overall Quality Evenness of Color Distribution of Oiliness Appearance (Cheese Only) Chocolate and Cheese Appearance Attribute

Figure 4.25: Graphical representation of descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 20% chocolate chips.

Overall Quality Appearance 10.00

8.00

6.00 SS-20% BS-20% 4.00

2.00

Oiliness 0.00 Evenness of Color (Cheese Only)

Distribution of Chocolate and Cheese

Figure 4.26: Spider plot for descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 20% chocolate chips. 113 3.50

3.00

2.50

2.00 SS-20% BS-20% 1.50 Mean Value

1.00

0.50

0.00 Bitter Salty Sweet Sour Umami Basic Taste

Figure 4.27: Graphical representation of descriptive basic taste attributes intensity meansof Cheddar cheeses with semi-sweet 20% and bittersweet 20% chocolate chips.

Bitter 3.50 3.00 2.50 2.00 1.50 SS-20% Umami 1.00 Salty BS-20% 0.50 0.00

Sour Sweet

Figure 4.28: Spider plot for descriptive basic taste attributes intensity means of Cheddarcheeses with semi-sweet 20% and bittersweet 20% chocolate chips.

114 6.00

5.00

4.00

SS-20% 3.00 BS-20% Mean Value 2.00

1.00

0.00

y y y y y d e) ey fur th ld tt it vor n l ru a ohol aci i Wh Su Ear Nu F fl lc y or Cooked e A Yeast hl ty/Mo at c( us r ree fatt he Cheese flavor M ocol F t Ch O Flavor Attribute

Figure 4.29: Graphical representation of descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 20% chocolate chips.

Figure 4.30: Spider plot for descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 20% chocolate chips. 115 12.00

10.00

8.00

SS-20% 6.00 BS-20% Mean Value 4.00

2.00

0.00 Springiness Crumbliness Firmness Texture Attribute

Figure 4.31: Graphical representation of descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 20% chocolate chips.

Springiness 12.00 10.00 8.00 6.00 SS-20% 4.00 BS-20% 2.00 0.00

Firmness Crumbliness

Figure 4.32: Spider plot for descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 20% chocolate chips.

116 10.00

9.00

8.00

7.00

6.00 SS-20% 5.00 BS-15%

Mean Value 4.00

3.00

2.00

1.00

0.00 Overall Quality Evenness of Color Distribution of Oiliness Appearance (Cheese Only) Chocolate and Cheese Appearance Attribute

Figure 4.33: Graphical representation of descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 15% chocolate chips.

Overall Quality Appearance 10.00 8.00 6.00

4.00 SS-20% 2.00 BS-15% Oiliness 0.00 Evenness of Color (Cheese Only)

Distribution of Chocolate and Cheese

Figure 4.34: Spider plot for descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 15% chocolate chips.

117 3.50

3.00

2.50

2.00 SS-20% BS-15% 1.50 Mean Value

1.00

0.50

0.00 Bitter Salty Sweet Sour Umami Basic Taste

Figure 4.35: Graphical representation of descriptive basic taste attributes intensity means between semi-sweet 20% and bittersweet 15% Cheddar cheeses with chocolate chips.

Bitter 3.50 3.00 2.50 2.00

1.50 SS-20% Umami Salty 1.00 BS-15% 0.50 0.00

Sour Sweet

Figure 4.36: Spider plot for descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 15% chocolate chips. 118 4.50

4.00

3.50

3.00

2.50 SS-20% 2.00 BS-15% Mean Value 1.50

1.00

0.50

0.00

) e) or ed ey ur y or ol d v lf thy ity n la ok u ar ru av easty aci ri f Wh S E Nutt F coh y lo e Co Al Y h es sty/Moldy c e u olate fl er( Ch M c th ho Free fatt C O Flavor Attribute

Figure 4.37: Graphical representation of descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 15% chocolate chips.

Cheese flavor 4.50 Other(chlorine) 4.00 Cooked 3.50 3.00 Free fatty acid 2.50 Whey 2.00 1.50 1.00 SS-20% Yeasty 0.50 Sulfur BS-15% 0.00

Alcohol Earthy

Chocolate flavor Musty/Moldy

Fruity Nutty

Figure 4.38: Spider plot for descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 15% chocolate chips. 119 12.00

10.00

8.00

SS-20% 6.00 BS-15% Mean Value 4.00

2.00

0.00 Springiness Crumbliness Firmness Texture Attribute

Figure 4.39: Graphical representation of descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 15% chocolate chips.

Springiness 12.00 10.00

8.00 SS-20% 6.00 BS-15% 4.00 2.00 0.00

Firmness Crumbliness

Figure 4.40: Spider plot for descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 20% and bittersweet 15% chocolate chips.

120 9.00

8.00

7.00

6.00

5.00 SS-15% 4.00 BS-20% Mean Value Value Mean 3.00

2.00

1.00

0.00 Overall Quality Evenness of Color Distribution of Chocolate Oiliness Appearance (Cheese Only) and Cheese Appearance Attribute

Figure 4.41: Graphical representation of descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 20% chocolate chips.

Overall Quality Appearance 10.00 8.00 SS-15% 6.00 BS-20% 4.00 2.00 Oiliness 0.00 Evenness of Color (Cheese Only)

Distribution of Chocolate and Cheese

Figure 4.42: Spider plot for descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 20% chocolate chips. 121 4.00

3.50

3.00

2.50

SS-15% 2.00 BS-20%

Mean Value 1.50

1.00

0.50

0.00 Bitter Salty Sweet Sour Umami Basic Taste

Figure 4.43: Graphical representation of descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 20% chocolate chips.

Bitter 4.00 3.50 SS-15% 3.00 BS-20% 2.50 2.00 1.50 Umami Salty 1.00 0.50 0.00

Sour Sweet

Figure 4.44: Spider plot for descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 20% chocolate chips. 122 6.00

5.00

4.00

SS-15% 3.00 BS-20% Mean Value 2.00

1.00

0.00

y r y y y y d or ed e u h dy tt it or ol e) v lf u in la ok rt lav aci f Wh Su Ea Mol N Fru coh y or e Co / e f Al Yeast tt hl ty at a c ees s l r( u ee f e Ch M oco r h h F C Ot Flavor Attribute

Figure 4.45: Graphical representation of descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 20% chocolate chips.

Cheese flavor 6.00 Other(chlorine) Cooked 5.00 SS-15% 4.00 Free fatty acid Whey BS-20% 3.00 2.00

Yeasty 1.00 Sulfur 0.00

Alcohol Earthy

Chocolate flavor Musty/Moldy

Fruity Nutty

Figure 4.46: Spider plot for descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 20% chocolate chips. 123 14.00

12.00

10.00

8.00 SS-15%

BS-20% 6.00 Mean Value

4.00

2.00

0.00 Springiness Crumbliness Firmness Texture Attribute

Figure 4.47: Graphical representation of descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 20% chocolate chips. .

Springiness 12.00 10.00 8.00

6.00 SS-15% 4.00 BS-20% 2.00 0.00

Firmness Crumbliness

Figure 4.48: Spider plot for descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 20% chocolate chips. 124 10.00

9.00

8.00

7.00

6.00 SS-15% 5.00 BS-15%

Mean Value 4.00

3.00

2.00

1.00

0.00 Overall Quality Evenness of Color Distribution of Oiliness Appearance (Cheese Only) Chocolate and Cheese Appearance Attribute

Figure 4.49: Graphical representation of descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips.

Overall Quality Appearance 10.00 8.00 6.00 4.00 SS-15% 2.00 BS-15% Evenness of Color (Cheese Oiliness 0.00 Only)

Distribution of Chocolate and Cheese

Figure 4.50: Spider plot for descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips. 125 4.00

3.50

3.00

2.50

SS-15% 2.00 BS-15%

Mean Value 1.50

1.00

0.50

0.00 Bitter Salty Sweet Sour Umami Basic Taste

Figure 4.51: Graphical representation of descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips.

Bitter 4.00 3.50 3.00 2.50 2.00 1.50 Umami Salty SS-15% 1.00 BS-15% 0.50 0.00

Sour Sweet

Figure 4.52: Spider plot for descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips.

126 4.50

4.00

3.50

3.00

2.50 SS-15% 2.00 BS-15% Mean Value 1.50

1.00

0.50

0.00

r y r y y ty r ol ty d e) ed e u thy ld tt i o h ci n k lf o u u av as a ri Wh u N l y o oo S Ear /M Fr Ye l se flavo C e f Alco sty (ch ee u er Ch M ocolat ree fatt h hC F Ot Flavor Attribute

Figure 4.53: Graphical representation of descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips.

Cheese flavor 5.00 Other(chlorine) Cooked 4.00

Free fatty acid 3.00 Whey

2.00

1.00 SS-15% Yeasty Sulfur BS-15% 0.00

Alcohol Earthy

Chocolate flavor Musty/Moldy

Fruity Nutty

Figure 4.54: Spider plot for descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips.

127 14.00

12.00

10.00

8.00 SS-15% BS-15% 6.00 Mean Value

4.00

2.00

0.00 Springiness Crumbliness Firmness Texture Attribute

Figure 4.55: Graphical representation of descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips.

Springiness 12.00 10.00 8.00 6.00 SS-15% 4.00 BS-15% 2.00 0.00

Firmness Crumbliness

Figure 4.56: Spider plot for descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 15% and bittersweet 15% chocolate chips.

128 Figure 4.57:Graphicalrepresentationofdescriptive appearanceattributesintensitymeans Figure 4.58:Spiderplot for descriptiveappearanceattributes intensity means ofCheddar

Mean Values 10.00 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 chips. of Cheddarcheeseswith bittersweet 15%andbittersweet20%chocolate cheeses with bittersweet15%and bittersweet20%chocolatechips. Overall Quality Appearance

Oiliness Evenness ofColor (Cheese Only)(Cheese Distribution of Chocolate 10.00 Overall Quality Overall Quality Appearance Attribute 0.00 2.00 4.00 6.00 8.00 Appearance Appearance and Cheese and Cheese 129 129

Chocolate and CheeseChocolate and

Distribution of Evenness of Color (Cheese (Cheese ofColor Evenness Oiliness Only) 20% 15% 20% 20% 15% 

3.50

3.00

2.50

2.00 15% 20% 1.50 Mean Values Mean Values

1.00

0.50

0.00 Bitter Salty Sweet Sour Umami Basic Taste Figure 4.59: Graphical representation of descriptive basic taste attributes intensity means of Cheddar cheeses with bittersweet 15% and bittersweet 20% chocolate chips.

Bitter 3.50 3.00 2.50 2.00 1.50 Umami 1.00 Salty 15% 20% 0.50 0.00

Sour Sweet

Figure 4.60: Spider plot for descriptive basic taste attributes intensity means of Cheddar cheeses with bittersweet 15% and bittersweet 20% chocolate chips.

130 6.00

5.00

4.00

15% 3.00 20%

Mean Values 2.00

1.00

0.00

ur y y y ty r y d e) ed ey th ld i vo n k lf o a aci ri oo Wh Su Ear Nutt Fru fl lcohol Yeast y lo C /M tla e A sty u er(ch Cheese flavor M oco h h Free fatt C Ot Flavor Attribute

Figure 4.61: Graphical representation of descriptive flavor attributes intensity means of Cheddar cheeses with bittersweet 15% and bittersweet 20% chocolate chips.

Cheese flavor 6.00 Other(chlorine) Cooked 5.00 4.00 Free fatty acid Whey 3.00 2.00 15% Yeasty 1.00 Sulfur 20% 0.00

Alcohol Earthy

Chocolate flavor Musty/Moldy

Fruity Nutty

Figure 4.62: Spider plot for descriptive flavor attributes intensity means of Cheddar cheeses with bittersweet 15% and bittersweet 20% chocolate chips. 131 12.00

10.00

8.00

15% 6.00 20% Mean Values 4.00

2.00

0.00 Springiness Crumbliness Firmness Texture Attribute

Figure 4.63: Graphical representation of descriptive texture attributes intensity means of Cheddar cheeses with bittersweet 15% and bittersweet 20% chocolate chips.

Springiness 12.00 10.00 8.00

6.00 15% 4.00 20% 2.00 0.00

Firmness Crumbliness

Figure 4.64: Spider plot for descriptive texture attributes intensity means of Cheddar cheeses with bittersweet 15% and bittersweet 20% chocolate chips. 132 9.00

8.00

7.00

6.00

5.00 15% 20% 4.00 Mean Values 3.00

2.00

1.00

0.00 Overall Quality Evenness of Color Distribution of Oiliness Appearance (Cheese Only) Chocolate and Cheese Appearance Attribute

Figure 4.65: Graphical representation of descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 15% and semi-sweet 20% chocolate chips.

Overall Quality Appearance 10.00

8.00 15% 6.00 20% 4.00 2.00 Oiliness 0.00 Evenness of Color (Cheese Only)

Distribution of Chocolate and Cheese

Figure 4.66: Spider plot for descriptive appearance attributes intensity means of Cheddar cheeses with semi-sweet 15% and semi-sweet 20% chocolate chips. 133 4.00

3.50

3.00

2.50

15% 2.00 20%

Mean Values Mean 1.50

1.00

0.50

0.00 Bitter Salty Sweet Sour Basic Tastes

Figure 4.67: Graphical representation of descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet 15% and semi-sweet 20% chocolate chips.

Bitter 4.00 3.50 3.00 2.50 2.00 1.50 Umami Salty 15% 1.00 20% 0.50 0.00

Sour Sweet

Figure 4.68: Spider plot for descriptive basic taste attributes intensity means of Cheddar cheeses with semi-sweet 15% and semi-sweet 20% chocolate chips. 134 4.50

4.00

3.50

3.00

2.50 15% 2.00 20%

Mean Values 1.50

1.00

0.50

0.00

r ) ey ur y y y ty or ol ty d e ed lf h ld tt h n ok rui av as flavo o Wh Su Nu F fl co C Eart e Ye se ty/Mo tla Al ee s fatty aci r(chlori h o ee e C Mu c h ho Fr C Ot Flavor Attribute

Figure 4.69: Graphical representation of descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 15% and semi-sweet 20% chocolate chips.

Cheese flavor 5.00 Other(chlorine) Cooked 4.00

Free fatty acid 3.00 Whey

2.00

1.00 Yeasty Sulfur 0.00 15% 20%

Alcohol Earthy

Chocolate flavor Musty/Moldy

Fruity Nutty

Figure 4.70: Spider plot for descriptive flavor attributes intensity means of Cheddar cheeses with semi-sweet 15% and semi-sweet 20% chocolate chips.

135 14.00

12.00

10.00

8.00 15% 20% 6.00 Mean Values Mean

4.00

2.00

0.00 Springiness Crumbliness Firmness Texture Attribute

Figure 4.71: Graphical representation of descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 15% and semi-sweet 20% chocolate chips.

Springiness 12.00 10.00 8.00 6.00 15% 4.00 20% 2.00 0.00

Firmness Crumbliness

Figure 4.72: Spider plot for descriptive texture attributes intensity means of Cheddar cheeses with semi-sweet 15% and semi-sweet 20% chocolate chips.

136 APPENDIX B

SCORESHEETS FOR THE CONSUMER PANELS, INGREDIENT

LISTS AND CONSENT FORMS

137 Product: Chocolate Cheese Date: 03-May-07

Please taste each sample. Rinse between samples with the water provided. Then rate each sample as follows: Each column should have only one check mark.

568 985 174 713 TEXTURE 568 985 174 713 APPEARANCE Like extremely Like extremely Like very much Like very much Like moderately Like moderately Like slightly Like slightly Neither like nor dislike Neither like nor dislike Dislike slightly Dislike slightly Dislike moderately Dislike moderately Dislike very much Dislike very much Dislike extremely Dislike extremely

568 985 174 713 FLAVOR 568 985 174 713 OVERALL LIKING Like extremely Like extremely Like very much Like very much Like moderately Like moderately Like slightly Like slightly Neither like nor dislike Neither like nor dislike Dislike slightly Dislike slightly Dislike moderately Dislike moderately Dislike very much Dislike very much Dislike extremely Dislike extremely

Please Rank the Samples According to Preference with 1st being the most preferred.

1st 2nd 3rd 4th

Comments:

138 Product: Chocolate Cheese Date: 5 Apr 07

Please taste each sample. Rinse between samples with the water provided. Then rate each sample as follows: Each column should have only one check mark.

894 116 381 968 TEXTURE 894 116 381 968 APPEARANCE Like extremely Like extremely Like very much Like very much Like moderately Like moderately Like slightly Like slightly Neither like nor dislike Neither like nor dislike Dislike slightly Dislike slightly Dislike moderately Dislike moderately Dislike very much Dislike very much Dislike extremely Dislike extremely

894 116 381 968 FLAVOR 894 116 381 968 OVERALL LIKING Like extremely Like extremely Like very much Like very much Like moderately Like moderately Like slightly Like slightly Neither like nor dislike Neither like nor dislike Dislike slightly Dislike slightly Dislike moderately Dislike moderately Dislike very much Dislike very much Dislike extremely Dislike extremely

Please Rank the Samples According to Preference with 1st being the most preferred.

1st 2nd 3rd 4th

Comments:

139 Product: Chocolate Cheese Date: 10 Apr 07

Please taste each sample. Rinse between samples with the water provided. Then rate each sample as follows: Each column should have only one check mark.

758 693 431 256 TEXTURE 758 693 431 256 APPEARANCE Like extremely Like extremely Like very much Like very much Like moderately Like moderately Like slightly Like slightly Neither like nor dislike Neither like nor dislike Dislike slightly Dislike slightly Dislike moderately Dislike moderately Dislike very much Dislike very much Dislike extremely Dislike extremely

758 693 431 256 FLAVOR 758 693 431 256 OVERALL LIKING Like extremely Like extremely Like very much Like very much Like moderately Like moderately Like slightly Like slightly Neither like nor dislike Neither like nor dislike Dislike slightly Dislike slightly Dislike moderately Dislike moderately Dislike very much Dislike very much Dislike extremely Dislike extremely

Please Rank the Samples According to Preference with 1st being the most preferred.

1st 2nd 3rd 4th

Comments:

140 Do you have allergies?

If you are allergic to the following ingredients please do not participate in Today’s panel. Thank You.

DAIRY CREAM CHEESE CHOCOLATE WHEY POWDER NONFAT DRY MILK SOY PRODUCTS

x Sugar x Cocoa Butter x Cocoa proc. w/alkali x Butter x Unsweetened Chocolate x Sweet Chocolate x Soy Lecithin x Chocolate x Vanilla x Cocoa x Chocolate Liquor proc. x Vegetable Shortening w/alkali Soybean Oil Fully Hydrogenated Cottonseed Oil Partially Hydrogenated Cottonseed and Soybean Oils Mono and Diglycerides TBHQ and Citric Acid (Antioxidants)

x Chocolate liquor x Vitamin A and D3 x Cheese x Trisodium Citrate Dihydrate Pasteurized Milk x Mono &Diglycerides Cheese Culture x Polysorbate 80 Salt x Carrageenan Enzymes Annatto (For Color)

141 Processed Chocolate Cheese Ingredients

Ghirardelli Chocolate Premium Baking Cocoa Sweet Ground Chocolate and Cocoa Sugar Cocoa Processed with Alkali Unsweetened Chocolate Soy Lecithin-An Emulsifier Vanilla

DC-35 BORDEAUX BR Semi-sweet Chocolate Coating Sugar Chocolate Liquor Processed with Alkali Chocolate Liquor Cocoa Butter Butterfat (Milk) Soy Lecithin added as an Emulsifier Vanilla

Baker’s German Brand Sweet Chocolate Bar Sweet Chocolate Sugar Chocolate Cocoa Butter Soy Lecithin (Emulsifier) Milk Solids

D-23-F Dutch ADM Cocoa High Fat Cocoa Processed with Alkali

Crisco All Vegetable Shortening Sticks Soybean Oil Fully Hydrogenated Cottonseed Oil Partially Hydrogenated Cottonseed and Soybean Oils Mono and Diglycerides TBHQ and Citric Acid (Antioxidants)

Kroger Sugar Granulated

Kroger Instant Nonfat Dry Milk Fortified with Vitamins A&D Nonfat Dry Milk Vitamin A & Vitamin D3

142 Kroger Natural Mild Cheese Pasteurized Milk Cheese Culture Salt Enzymes Annatto (For Color)

Stabilizer Fine Granular Trisodium Citrate Dyhydrate (YIXIN, Union-Biochemical Co., LTD.)

Whey Powder (Custer dairy processing plant at Mississippi State University)

Kroger Ultra-Pasteurized Heavy Whipping Cream Grade A Heavy Cream Skim Milk Contains less than 1% of each of the following ingredients Mono and Diglycerides Polysorbate 80 Carrageenan Contains 36% Milk Fat

143 Basic Taste Solutions used for the descriptive panels

Table 4.11: Basic taste solution-sweet (Used: Domino’s Sugar)

Amount of Sugar (g) Water (ml) Intensity 20 1000 2.0 50 1000 5.0 100 1000 10.0

Table 4.12: Basic taste solution-bitter {Used: Bell Aromatics Caffeine (Fine) USP Anhydrous}

Amount of caffeine (g) Water (ml) Intensity 0.5 1000 2.0 0.8 1000 5.0 1.5 1000 10.0

Table 4.13: Basic taste solution-sour (Used: ADM citric acid, USP FCC U Anhydrous Fine Granular, Archer Daniels Midland, Product # 020420)

Amount of citric acid(g) Water (ml) Intensity 0.5 1000 2 0.8 1000 5 1.5 1000 10

Table 4.14: Basic taste solution-salty (Used: Morton Iodized Salt)

Amount of salt (g) Water (ml) Intensity 2.0 1000 2.5 3.5 1000 5.0 5.0 1000 8.5

Table 4.15: Basic taste solution-umami (Used: Accent Flavor Enhancer)

Amount of MSG (g) Water (ml) Intensity 2.5 1000 1.5 5.0 1000 3.0 10.0 1000 6.0

144 Table 4.16: Products used for the descriptive panel.

Reference Standard Brand Name Company of Manufacturing Licorice Twizzlers Licorice Twists Y & S candies Naturally and Artificially Flavored Hershey, Pennsylvania 1 7033-0815, U.S.A

Tonic Water Schweppes Tonic Water Schweppes Contains Quinine Caramel America’s Classic Caramels Kraft Foods Global Inc. Traditional Northfield, IL 60093-2753 USA

Mushrooms Mushroom Buttons The Kroger Co. Cincinnatti, Ohio 45202 Evaporated Milk PET The Dairy Goodness Peoples The J.M. Smucker Company, Evaporated Milk Vitamin D added Orrville OH 44667, USA Whipping cream Heavy whipping cream Ultra- The Kroger Co. pasteurized Grade A Cincinnatti, Ohio 45202 Fresh Cheddar whey Mississippi State Dairy Plant Butter Unsalted Sweet Butter Land O’Lakes, Inc. Arden Hills, MN 55126 Parmesan Cheese Saputo Frigo Parmesan cheese Saputo Cheese USA Inc. Lincolnshire, IL 60069 Blue Cheese Amablu Blue Cheese Faribault Dairy Company Inc. Faribult, MN 55021 Mascarpone Mascarpone Mozarella Fresa Family of Italian Italian Cream Cheese cheese Cracker Barrel Extra Sharp Cracker Barrel Kraft Foods Global Inc. Natural Extra Sharp Cheddar cheese Northfield, IL 60093-2753 USA

Colby Cheese New Colby Cheese Kraft Foods Global, Inc., Northfield, IL 60093-2753 Velveeta Cheese Pasteurized prepared cheese product Kraft Foods Global, Inc., Northfield, IL 60093-2753 Provolone Cheese Sliced non-smoked provolone cheese Great Value Walmart Stores, Inc. Bentonville, AR 72716 Feta cheese Chunk feta cheese Inter-American Products, Inc. Premium quality private selection Cincinnatti, OH 45202 Vermont Cheddar Premium quality private selection Cabot Vermont Vermont extra sharp white Cheddar Private selection cheese Yeast Rolls Sister Schubert Sister Schubert

145 Table 4.17: Different Danish Blue cheese dilutions used for the descriptive panels

Dilution Amount of blue cheese (g) Amount of water for the make up (ml) 1:10 20 200 1:25 8 200 1:50 4 200 1:100 2 200 1:250 1 250 1:500 1 500 1:1000 1 1000

Replication 1

Types of chocolates used : 1. Real semi-sweet (Nestle’s Toll House) Mini chips 2. Bittersweet (Ghirardelli), Bigger chips Cheese Curd & Chocolate chips were mixed at the Mississippi State Dairy Plant Day of Mixing Curd & Chocolate : 01/16/2007 Day of Vacuum Packaging & Steam Sealing : 01/17/2007

Replication 2

Types of chocolates used : 1. Real semi-sweet (Nestle’s Toll House) Mini chips 2. Bittersweet (Ghirardelli), Bigger chips Cheese Curd & Chocolate chips were mixed at the Mississippi State Dairy Plant Day of Mixing Curd & Chocolate : 01/23/2007 Day of Vacuum Packaging & Steam Sealing : 01/24/2007

Replication 3

Types of chocolates used : 1. Real semi-sweet (Nestle’s Toll House) Mini chips 2. Bittersweet (Ghirardelli), Bigger chips Cheese Curd & Chocolate chips were mixed at the Mississippi State Dairy Plant Day of Mixing Curd & Chocolate : 01/25/2007 Day of Vacuum Packaging & Steam Sealing : 01/26/2007

146 147

Table 4.18: Replication 1 formulations for the Cheddar cheeses with chocolate chips.

% OF AGE AMT. (g) OF S.NO LABEL REPL. TYPE OF CHOC. CHOC. PERIOD CURD+CHOC. DAY 1 DAY 60 DAY 90 DAY 120 1 R1-SS-15-60 1 SEMI-SWEET 15 105 964.75+170.25 1/17/2007 3/17/2007 4/16/2007 5/16/2007 2 R1-SS-15-90 1 SEMI-SWEET 15 105 964.75+170.25 1/17/2007 3/17/2007 4/16/2007 5/16/2007 3 R1-SS-15-120 1 SEMI-SWEET 15 105 964.75+170.25 1/17/2007 3/17/2007 4/16/2007 5/16/2007 4 R1-SS-20-60 1 SEMI-SWEET 20 105 908+227 1/17/2007 3/17/2007 4/16/2007 5/16/2007 5 R1-SS-20-90 1 SEMI-SWEET 20 105 908+227 1/17/2007 3/17/2007 4/16/2007 5/16/2007 6 R1-SS-20-120 1 SEMI-SWEET 20 105 908+227 1/17/2007 3/17/2007 4/16/2007 5/16/2007 7 R1-BS-15-60 1 BITTERSWEET 15 105 964.75+170.25 1/17/2007 3/17/2007 4/16/2007 5/16/2007 8 R1-BS-15-90 1 BITTERSWEET 15 105 964.75+170.25 1/17/2007 3/17/2007 4/16/2007 5/16/2007 9 R1-BS-15-120 1 BITTERSWEET 15 105 964.75+170.25 1/17/2007 3/17/2007 4/16/2007 5/16/2007 10 R1-SS-20-60 1 BITTERSWEET 20 105 908+227 1/17/2007 3/17/2007 4/16/2007 5/16/2007 11 R1-SS-20-90 1 BITTERSWEET 20 105 908+227 1/17/2007 3/17/2007 4/16/2007 5/16/2007 12 R1-SS-20-120 1 BITTERSWEET 20 105 908+227 1/17/2007 3/17/2007 4/16/2007 5/16/2007 13 CONTROL 1 WITHOUT CHOC. 0 105 1135 1/17/2007 3/17/2007 4/16/2007 5/16/2007

*All the samples belonging to Replication I were utilized for the training of the panelists for descriptive analysis. 148

Table 4.19: Replication 2 formulations for the Cheddar cheeses with chocolate chips.

% OF AGE AMT. (g) OF S.NO LABEL REPL. TYPE OF CHOC. CHOC. PERIOD CURD+CHOC. DAY 1 DAY 60 DAY 90 DAY 120 14 R2-SS-15-60 2 SEMI-SWEET 15 105 964.75+170.25 1/24/2007 3/24/2007 4/23/2007 5/23/2007 15 R2-SS-15-90 2 SEMI-SWEET 15 105 964.75+170.25 1/24/2007 3/24/2007 4/23/2007 5/23/2007 16 R2-SS-15-120 2 SEMI-SWEET 15 105 964.75+170.25 1/24/2007 3/24/2007 4/23/2007 5/23/2007 17 R2-SS-20-60 2 SEMI-SWEET 20 105 908+227 1/24/2007 3/24/2007 4/23/2007 5/232007 18 R2-SS-20-90 2 SEMI-SWEET 20 105 908+227 1/24/2007 3/24/2007 4/23/2007 5/23/2007 19 R2-SS-20-120 2 SEMI-SWEET 20 105 908+227 1/24/2007 3/24/2007 4/23/2007 5/23/2007 20 R2-BS-15-60 2 BITTERSWEET 15 105 964.75+170.25 1/24/2007 3/24/2007 4/23/2007 5/23/2007 21 R2-BS-15-90 2 BITTERSWEET 15 105 964.75+170.25 1/24/2007 3/24/2007 4/23/2007 5/23/2007 22 R2-BS-15-120 2 BITTERSWEET 15 105 964.75+170.25 1/24/2007 3/24/2007 4/23/2007 5/232007 23 R2-SS-20-60 2 BITTERSWEET 20 105 908+227 1/24/2007 3/24/2007 4/23/2007 5/23/2007 24 R2-SS-20-90 2 BITTERSWEET 20 105 908+227 1/24/2007 3/24/2007 4/23/2007 5/23/2007 25 R2-SS-20-120 2 BITTERSWEET 20 105 908+227 1/24/2007 3/24/2007 4/23/2007 5/23/2007 26 CONTROL 2 WITHOUT CHOC. 0 105 1135 1/24/2007 3/24/2007 4/23/2007 5/23/2007 149

Table 4.20: Replication 3 formulations for the Cheddar cheeses with chocolate chips.

TYPE % OF AGE AMT. (g) OF S.NO LABEL REPL. OF CHOC. CHOC. PERIOD CURD+CHOC. DAY 1 DAY 60 DAY 90 DAY 120 27 R3-SS-15-60 3 SEMI-SWEET 15 105 964.75+170.25 1/26/2007 3/26/2007 4/25/2007 5/25/2007 28 R3-SS-15-90 3 SEMI-SWEET 15 105 964.75+170.25 1/26/2007 3/26/2007 4/25/2007 5/25/2007 29 R3-SS-15-120 3 SEMI-SWEET 15 105 964.75+170.25 1/26/2007 3/26/2007 4/25/2007 5/25/2007 30 R3-SS-20-60 3 SEMI-SWEET 20 105 908+227 1/26/2007 3/26/2007 4/25/2007 5/25/2007 31 R3-SS-20-90 3 SEMI-SWEET 20 105 908+227 1/26/2007 3/26/2007 4/25/2007 5/25/2007 32 R3-SS-20-120 3 SEMI-SWEET 20 105 908+227 1/26/2007 3/26/2007 4/25/2007 5/25/2007 33 R3-BS-15-60 3 BITTERSWEET 15 105 964.75+170.25 1/26/2007 3/26/2007 4/25/2007 5/25/2007 34 R3-BS-15-90 3 BITTERSWEET 15 105 964.75+170.25 1/26/2007 3/26/2007 4/25/2007 5/25/2007 35 R3-BS-15-120 3 BITTERSWEET 15 105 964.75+170.25 1/26/2007 3/26/2007 4/25/2007 5/25/2007 36 R3-SS-20-60 3 BITTERSWEET 20 105 908+227 1/26/2007 3/26/2007 4/25/2007 5/25/2007 37 R3-SS-20-90 3 BITTERSWEET 20 105 908+227 1/26/2007 3/26/2007 4/25/2007 5/25/2007 38 R3-SS-20-120 3 BITTERSWEET 20 105 908+227 1/26/2007 3/26/2007 4/25/2007 5/25/2007 39 CONTROL 3 WITHOUT CHOC. 0 105 1135 1/26/2007 3/26/2007 4/25/2007 5/25/2007 Processed Chocolate Cheese Codes for Consumer Panels Chocolate Cheese GSR 1023 lli ed lli ADM an a h c ir t hG erm Du G Bordeaux Rep # 1 894 116 381 968 Rep # 2 Rep # 3 Chocolate Cheese

Chocolate Cheese GSR 1023 x lli ADM eau adeGhir tch rd oB Du German Rep # 1 Rep # 2 758 648 431 256 Rep # 3 Chocolate Cheese

Chocolate Cheese GSR 1023 x lli ed ADM an eau a h ct ir rd h erm o Du G B G Rep # 1 Rep # 2 Rep # 3 568 985 174 713 Chocolate Cheese

150 CONSENT FORM (You Must Be 18 Years Old to Participate)

Title of Study: Development of a Chocolate Cheese Product

Study Site: Garrison Sensory Evaluation Laboratory and/or Mississippi State University Campuses, Off-Site Facilities and Locations

Name of Researcher(s) & University affiliation: ¾ Vishal Royyala, Mississippi State University, Graduate Student ¾ Dr. Patti C. Coggins, Director, Garrison Sensory Lab, Mississippi State University

What is the purpose of this research project? To determine consumer acceptability of a Chocolate Cheese Product.

How will the research be conducted? You will be given samples of product to taste and compare, and will be asked to fill out a questionnaire.

Are there any risks or discomforts to me because of my participation? No

Does participation in this research provide any benefits to others or myself? Yes. Results of this study may provide the consumer with a new type food choice and will benefit soy producers by increasing demand.

Will this information be kept confidential? Yes

Who do I contact with research questions? If you should have any questions about this research project, please feel free to contact Dr. Patti C. Coggins, 662-325-4002. For additional information regarding your rights as a research subject, please feel free to contact the MSU Regulatory Compliance Office at 662-325- 3294.

**If the study is physical in nature or is considered by the IRB to be more than minimal risk the following question must be included: What do I do if I am injured at a result of this research? In addition to reporting an injury to Dr. Patti C. Coggins, 662-325-4002 and to the Regulatory Compliance Office (662-325-3294), you may be able to obtain limited compensation from the State of Mississippi if the injury was caused by the negligent act of a state employee where the damage is a result of an act for which payment may be made under §11-46-1, et seq. Mississippi Code Annotated 1972. To obtain a claim form, contact the University Police Department at MSU UNIVERSITY POLICE DEPARTMENT, Butler-Williams Bldg, Mississippi State, MS 39762, (662) 325-2121.

What if I do not want to participate? Please understand that your participation is voluntary, your refusal to participate will involve no penalty or loss of benefits to which you are otherwise entitled, and you may discontinue your participation at any time without penalty or loss of benefits.

You will be offered a copy of this form for your records.

______Investigator Signature Date

151 CONSENT FORM (You Must Be 18 Years Old to Participate)

Title of Study: Development of a Chocolate Cheese Product

Study Site: Garrison Sensory Evaluation Laboratory and/or Mississippi State University Campuses, Off-Site Facilities and Locations

Name of Researcher(s) & University affiliation: ¾ Vishal Royyala, Mississippi State University, Graduate Student ¾ Dr. Patti C. Coggins, Director, Garrison Sensory Lab, Mississippi State University

What is the purpose of this research project? To determine quality attributes of a Chocolate Cheese Product.

How will the research be conducted? You will be given samples of product to taste and compare, and will be asked to fill out a questionnaire.

Are there any risks or discomforts to me because of my participation? No

Does participation in this research provide any benefits to others or myself? Yes. Results of this study may provide the consumer with a new type food choice and will benefit cheese manufacturers by increasing demand.

Will this information be kept confidential? Yes

Who do I contact with research questions? If you should have any questions about this research project, please feel free to contact Dr. Patti C. Coggins, 662-325-4002. For additional information regarding your rights as a research subject, please feel free to contact the MSU Regulatory Compliance Office at 662-325- 3294.

**If the study is physical in nature or is considered by the IRB to be more than minimal risk the following question must be included: What do I do if I am injured at a result of this research? In addition to reporting an injury to Dr. Patti C. Coggins, 662-325-4002 and to the Regulatory Compliance Office (662-325-3294), you may be able to obtain limited compensation from the State of Mississippi if the injury was caused by the negligent act of a state employee where the damage is a result of an act for which payment may be made under §11-46-1, et seq. Mississippi Code Annotated 1972. To obtain a claim form, contact the University Police Department at MSU UNIVERSITY POLICE DEPARTMENT, Butler-Williams Bldg, Mississippi State, MS 39762, (662) 325-2121.

What if I do not want to participate? Please understand that your participation is voluntary, your refusal to participate will involve no penalty or loss of benefits to which you are otherwise entitled, and you may discontinue your participation at any time without penalty or loss of benefits.

You will be offered a copy of this form for your records.

______Panelist Signature Date ______Investigator Signature Date _ 152 APPENDIX C

SCORE SHEET FOR THE DESCRIPTIVE PANEL

153 Sensory Evaluation of Aged Cheddar cheeses with chocolate chips Descriptive Panel

Time Period for Aging: 110 Days

Date______Time______Panelist Code______Gender: F M

0 = low intensity 15 = high intensity

APPEARANCE:

Overall appearance

фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф 

Evenness of color (Cheese Only)

фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  Very Uneven Very Even

Distribution of Chocolate and Cheese

фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  Un-Evenly Distributed Evenly Distributed

Oiliness: The degree to which the excess amount of oil is perceived on the skin. Reference – Plant cheese set outside before the panel for 1 to 2 hours

фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  Not Oily Very Oily

154 BASIC TASTES:

Bitter: Reference – Caffeine anhydrous (2, 5, 10)

фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  None Extreme

Salty: Reference – Salt solution (2.5, 5, 8.5)

фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  None Extreme

Sweet: Reference – Sugar solution (2, 5, 10)

фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  None Extreme

Sour: Reference – Citric acid (2, 5, 10)

фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  None Extreme

Umami: Reference – MSG (1.5, 3, 6)  фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  None Extreme

155 FLAVOR:

Cheese Flavor: Reference – Vermont Style Cheddar (12) Vermont фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  No Cheese Flavor Intense Cheese Flavor  Cooked: Reference - Evaporated milk (9), Velveeta (12) Evap. Milk Velveeta фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  No Cooked Flavor Extreme Cooked Flavor

Whey: Reference – Fresh Cheddar Whey Whey фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  None Extreme

Sulfur: Reference – NY (10), Vermont cheese (13) NY Vermont фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  None Extreme  Earthy: Reference - Mushrooms (Raw-Sliced) (4.5) Mushroom фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  None Extreme

Musty/Moldy: Reference – Danish Blue Cheese (1:25 (8), 1:250 (4), 1:1000 (1)); Brie (4) Brie фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  None Extreme

Nutty: Reference – Roasted Unsalted Almonds (5) Almonds фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  No Nutty Flavor Extreme Nutty Flavor

156 Fruity: Reference – Pineaple Juice (1:10 (7), 1:100 (1))  фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  No Fruity Flavor Extreme Fruity Flavor

Chocolate Flavor: Reference – Baker’s German Sweet (5.5), Nestle’s Semisweet (7), Ghirardelli Bittersweet (8.5), Hershey’s Special Dark Cocoa Powder (8.5), Baker’s German Unsweet (12.5)

фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  No Chocolate Flavor Intense Chocolate Flavor   Alcohol: Reference – Ethanol (1:100 (1), 3:100 (4))

фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  No Alcohol Flavor Intense Alcohol Flavor

Yeasty: Reference - Yeast Roll (4) Yeast Roll фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  No Yeasty Flavor Extreme Yeasty Flavor   Free fatty acid: Reference – feta cheese (10)  feta фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  None Extreme

Other:______ фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф 

157 TEXTURE:

Hand Evaluated Texture:

Springiness: The degree to which the sample deforms under stress, but returns to its original shape when stress is removed. Reference – Large Erasers (15) Large Eraser фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  No recovery Very springy

Crumbliness: The degree to which the samples fractures rather than deforms during the course of working the sample in the hand 3 to 6 times. Reference – Feta (13) Feta фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAAфAAAAфAAAAф  Not crumbly Very crumbly

Firmness: The force required to compass between thumb and index finger. Reference – Cool Whip (0); Jumbo Marshmallow (2); Dry Wine Bottle Cork (15) Cool WhipMmDry Cork фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф  No Force High Force

Other:______ фAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAфAAAAф 

158