A Title: Development of Healthy Chicken Nuggets with Konjac Flour, Shiitake Mushroom and Quinoa Researcher: Assoc.Prof. Adisak Akesowan Department of Food Science and Technology School of Science and Technology University of the Thai Chamber of Commerce Year of Accomplishment: 2015 No. of Pages: 85 Pages Keywords: Konjac flour, Shiitake mushroom, Quinoa, Chicken nugget, Health food. Abstract This research was aimed to develop a healthy chicken nugget which targeted to lower in fat, free from phosphate and reduce in meat protein content. Initially, the performance of two variables, i.e. konjac/xanthan (3:1) blend (0.2-1.5%, w/w) and shiitake powder (1-4%, w/w) for optimizing a best formulation of low-fat, phosphate-free nuggets was studied. A 13-experimental run was carried out by a central composite rotatable design, and the influence of variables on physical properties (peak force and internal color) and sensory characteristics of nuggets was investigated. Linear, quadratic and interaction effect of variables were found for physical and sensory responses. Addition of konjac/xanthan blend and shiitake powder, both at low level, resulted in increasing nugget peak force; however, higher amount of these variables lowered the peak force. The nugget became darker with more shiitake powder added. With 1.8-3% addition of shiitake powder, low-fat, nuggets presented good sensory acceptance, as observed for a rise in score for color, taste, flavor and overall acceptability. The optimal condition for the low-fat, The research was financially supported by the University of the Thai Chamber of Commerce. B phosphate-free nugget consisted of 0.39% konjac/xanthan blend and 1.84% shiitake powder. Secondly, the study purposed to investigate an appropriate condition for replacing chicken meat with cooked quinoa seed in a recommended low-fat, phosphate-free nugget. The quinoa replacement was designed to 0, 10, 20, 30 and 40% by chicken meat weight. The obtained results showed that an increase in quinoa replacement resulted in significant decreases (p<0.05) in yield, moisture content and higher total fluid release. The nugget was darker with increasing level of quinoa. A 20% quinoa replacement was appeared to markedly improve the nugget in terms of hardness and chewiness. Nevertheless, the nugget with 30% quinoa had all textural characteristics such as hardness, cohesiveness, springiness and chewiness equivalent to the control sample (no quinoa). On a 9-point hedonic scale, an increase in panelists’ scores for sensory attributes was evident in nuggets with increasing amounts of quinoa 10 up to the 30% level. The nugget with 30% quinoa had significantly (p<0.05) better sensorial characteristics than the control sample. This product also provides a dietary fiber content approximately 7.6-fold higher that found in 100% fat standard nugget. The last study was to evaluate the storage stability and the sensory acceptance of three formulations; a standard nugget and two low-fat, phosphate-free nuggets, one with no quinoa and another with 30% quinoa. After a period of 75 days of storage at -18 ºC, the results revealed decreases in moisture content and internal lightness (L*) and redness (a*), while TBA (thiobarbituric acid) development was slightly changed in all nugget formulations. The products had obviously lowered hardness, whereas cohesiveness, springiness and chewiness had slightly changed or fluctuated in narrow range. The nuggets were microbiologically safe during storage and also well accepted for all sensory attributes. C ACKNOWLEDGEMENT The author would like to thank the University of the Thai Chamber of Commerce for a research fund. The author is also thankful to the professional reviewers for their valuable suggestions and corrections, which help to improve the quality of this research. Assoc.Prof. Adisak Akesowan July, 2015 D CONTENTS PAGE ABSTRACT A ACKNOWLEDGEMENT C CONTENTS D LIST OF TABLES E LIST OF FIGURES G CHAPTER 1. INTRODUCTION 1 2. LITERATURE REVIEW 7 3. RESEARCH METHODOLOGY 30 4. RESULTS AND DISCUSSION 39 5. CONCLUSION 75 REFERENCES 77 E LIST OF TABLES TABLE PAGE 2.1 Applications and functional uses of konjac flour 12 2.2 Chemical composition, essential amino acid profile, vitamins and 20 minerals composition of quinoa 3.1 Standard formulation of chicken nugget 31 3.2 Experimental design matrix for low-fat, phosphate-free chicken 33 nuggets with various levels of konjac/xanthan blend and shiitake powder 4.1 Results of physical properties of low-fat, phosphates-free chicken 40 nuggets with various levels of konjac/xanthan blend and shiitake powder 4.2 Regression coefficients of peak force and internal color of low-fat, 31 phosphate-free chicken nuggets with various levels of konjac/xanthan blend and shiitake powder 4.3 Experimental conditions and sensory results of low-fat, phosphate-free 45 chicken nuggets with various levels of konjac/xanthan blend and shiitake powder 4.4 Regression coefficients of sensory results of low-fat, phosphate-free 46 chicken nuggets with various levels of konjac/xanthan blend and shiitake powder 4.5 Criteria and outputs for numerical optimization of low-fat, phosphate- 51 free nuggets 4.6 Sensory scores of low-fat, phosphate-free nuggets containing quinoa 60 F TABLE PAGE 4.7 Chemical composition of uncooked and cooked nuggets 61 4.8 Free amino acids (mg/100 g) and taste components of nugget 64 formulations 4.9 Microbiological counts (log CFU/g) for three nugget formulations 72 stored at -18 C for 75 days G LIST OF FIGURES FIGURE PAGE 2.1 Structure of konjac flour 8 2.2 Some edible mushrooms 14 2.3 Fresh shiitake and shiitake powder 16 2.4 Raw and cooked quinoa seed 19 4.1 Response surface graphs of physical properties of low-fat, 44 phosphate-free chicken nuggets with various levels of konjac/xanthan blend and shiitake powder: (a) peak force, (b) lightness (L*), (c) redness (a*) and (d) yellowness (b*) 4.2 Response surface graphs of sensory attributes of low-fat, phosphate- 50 free chicken nuggets under various levels of konjac/xanthan blend and shiitake powder: (a) appearance, (b) color, (c) taste, (d) flavor, (e) texture and (f) overall acceptability 4.3 Physical properties of low-fat, phosphate-free nuggets with various 53 levels of quinoa: (a) yield, (b) moisture content and (c) total fluid release. C = low-fat, phosphate-free nugget (control) and S1 to S4 = low-fat, phosphate-free nuggets containing 10, 20, 30 and 40%quinoa, respectively. Equal lowercase letters are not significantly different (p>0.05) 4.4 Internal color of low-fat, phosphate-free nuggets with various levels 55 of quinoa. C and S1 to S4 codes refer to Fig. 4.3 4.5 Textural characteristics of low-fat, phosphate-free nuggets with 56 various levels of quinoa: (a) hardness, (b) cohesiveness, (c) springiness and (d) chewiness. C and S1 to S4 codes refer to Fig. 4.3. Equal lowercase letters are not significantly different (p>0.05) H FIGURE PAGE 4.6 Physical properties of three nugget formulations stored at -18 C for 66-67 75 days: (a) pH, (b) moisture content, (c) lightness, (d) redness and (e) yellowness. C = standard nugget, T1 and T2 = low-fat, phosphate-free nuggets containing 0 and 30% quinoa, respectively. Equal capital letters are not significantly different regarding storage time (p>0.05). Equal lowercase letters are not significantly different regarding formulation (p>0.05) 4.7 Textural characteristics of three nugget formulations stored at -18 C 70 for 75 days: (a) hardness, (b) cohesiveness, (c) springiness and (d) chewiness. C, T1 and T2 codes refer to Fig. 4.6. Equal capital letters are not significantly different regarding storage time (p>0.05). Equal lowercase letters are not significantly different regarding formulation (p>0.05) 4.8 Thiobarbituric acid (TBA) values of three nugget formulations stored 71 at -18 C for 75 days. C, T1 and T2 codes refer to Fig. 4.6. Equal capital letters are not significantly different regarding storage time (p>0.05). Equal lowercase letters are not significantly different regarding formulation (p>0.05) 4.9 Sensory evaluation of three nugget formulations stored at -18 C for 73-74 75 days: (a) color, (b) taste, (c) flavor, (d) texture and (e) overall acceptability. C, T1 and T2 codes refer to Fig. 4.6. Equal capital letters are not significantly different regarding storage time (p>0.05). Equal lowercase letters are not significantly different regarding formulation (p>0.05) 1 CHAPTER 1 INTRODUCTION 1.1 Statement of purpose In the modern day, meat products that are low in fat and harmful ingredients like phosphates and nitrite, but high in beneficial health-promoting ingredients including dietary fiber, functional and antioxidant-rich substances are being increasingly consumed, although most of these products are somewhat expensive. This is because of consumer awareness regarding preventing or avoiding the risks of fat-related diseases including cardiovascular disease, diabetes, obesity, hypertension and certain cancers (Ozvural and Vural, 2008). Low-fat meat products have been investigated for their reductions in particular unhealthy ingredients such as animal fat, salt and phosphates (Mahmoud and Badr, 2011). In the manufacture of low-fat meat products, water, non-meat ingredients, hydrocolloids or gums and dietary fibers are used as fat replacers (Choi et al., 2008). Hydrocolloids such as carrageenan, konjac, xanthan and locust bean gum have contributed as fat replacers because of their very low caloric content, inexpensive cost and versatile applications as they can be added directly or prepared as fat analogues. Among these gums, konjac flour, a water soluble and non-ionic flour is of interest for applications in the food industry. The flour has been extensively used as an additive for gelling, thickening, texturizing and binding in various food products (Thomas, 1997).