ABSTRACT Title of Document: INCORPORATING GRAPE SEED ANTIOXIDANTS INTO A FUNCTIONAL FOOD MODEL Lena Binzer Rebecca Brinsko Jessica Cha Zao Chen Sarah Green Kelly Grob Junjie Hao Christina Hitz Laura Li Sowmya Swamy Maxim Wolf MengMeng Xu Mary Yanik Directed By: Dr. Liangli Yu, PhD, Department of Nutrition and Food Science Dr. Margaret Slavin, PhD, RD, Department of Nutrition and Food Science Consumption of foods rich in natural antioxidants may potentially reduce the risk of chronic illnesses. This study examined feasibility and consumer acceptability of creating a functional food rich in natural antioxidants from cold-pressed grape seed oil and flour. The first study investigated and compared five grape seed varieties, and found Chardonnay grape seeds contained the highest quantity of health-beneficial properties. Consequently, addition of Chardonnay grape seed flour and oil to bread significantly increased health-beneficial properties. Baking conditions influenced antioxidant properties of bread, indicating processing conditions may affect antioxidant activity in finished food products. In addition, the consumer sensory evaluation study found control bread was preferred over bread containing grape seed flour and oil; however, grape seed containing bread had an overall positive reception. Incorporation of grape seeds into bread may be effective in incorporating health-beneficial compounds into the diet; however, further studies on long term health effects should be conducted. INCORPORATING GRAPE SEED ANTIOXIDANTS INTO A FUNCTIONAL FOOD MODEL By Team Innovative Medicines for Maladies Utilizing Nutraceutical Enhancements (IMMUNE) Lena Binzer, Rebecca Brinsko, Jessica Cha, Zao Chen, Sarah Green, Kelly Grob, Junjie Hao, Christina Hitz, Laura Li, Sowmya Swamy, Maxim Wolf, MengMeng Xu, & Mary Yanik Thesis submitted in partial fulfillment of the requirements for the Gemstone Program, University of Maryland, College Park 2011 Advisory Committee: Dr. Liangli Yu, Mentor Dr. Margaret Slavin, Mentor Dr. William J. Kenworthy, Discussant Dr. Jeffrey Moore, Discussant Dr. Qin Wang, Discussant Dr. Thomas Wang, Discussant © Copyright by Team IMMUNE Lena Binzer, Rebecca Brinsko, Jessica Cha, Zao Chen, Sarah Green, Kelly Grob, Junjie Hao, Christina Hitz, Laura Li, Sowmya Swamy, Maxim Wolf, MengMeng Xu, & Mary Yanik 2011 Acknowledgements Our research over the past four years would not have been possible without the contribution and support from various members of industry, the scientific community, as well as the University of Maryland. We have many people to thank for their contributions towards the success of our project. Foremost, we would like to express our gratitude towards our research mentor, Dr. Liangli Yu, and co-mentor Dr. Margaret Slavin and our past co-mentor Dr. Mickey Parish, for their guidance, encouragement and support over the past 3.5 years. We would especially like to thank Dr. Yu for the extensive use of her laboratory, as well as her group members for their assistance and mentorship in obtaining and interpreting experimental results. We would also like to thank our committee members, Dr. William Kenworthy, Dr. Jeffrey Moore, Dr. Qin Wang, and Dr. Thomas Wang, for the time they took to provide constructive and detailed comments on our dissertation and expanding our vision of the project through their feedback. Many thanks to the Gemstone Program staff, for their insight and support of our project, from its conceptualization to its realization. Their continuing feedback has helped to shape and improve the project over the past 4 years. We would like thank our family and friends for their support and encouragement, which have motivated us through difficult times throughout our project. Financial support for this research was provided by ACC International Academic Collaborative Fellows Program, Maryland Grain Producers Utilization Board, Maryland Soybean Board, Botanical Oil Innovations Inc., and the University of Maryland Gemstone Program. In addition, material support in the form of whole wheat flour, and cold pressed ii grape seed flour and oil were provided by the Mennel Milling Company (Fostoria, OH) and Botanical Oil Innovations Inc. (Spooner, WI), respectively. Their tremendous contribution to the success of Team IMMUNE is gratefully acknowledged. iii Table of Contents Acknowledgements....................................................................................................... ii! List of Tables .............................................................................................................. vii! List of Figures............................................................................................................ viii! Chapter 1: Introduction..................................................................................................9! Introduction....................................................................................................................9! Chapter 2: Antioxidant Properties and Phenolic Components of Grape Seeds...........14! Introduction..................................................................................................................14! Phenolic Components ..................................................................................................15! Total Phenolic Content ................................................................................................15! Phenolic Composition of Grape Seeds ........................................................................24! Trans-Resveratrol ........................................................................................................30! Antioxidant Properties.................................................................................................31! Antioxidative Properties of Grape Seeds.....................................................................31! Effects of Post-Harvest Treatments on Grape Seed Antioxidants...............................38! Effects of Thermal Treatment......................................................................................38! Effects of Particle Size.................................................................................................43! Effects of Storage Conditions......................................................................................43! Considerations in Antioxidant Property Estimation for Grape Seeds .........................44! Summary......................................................................................................................45! Incorporation Into Functional Foods ...........................................................................45! Functional Foods: An Overview..................................................................................45! Antioxidants in Functional Foods................................................................................46! Bread as a Functional Food Model..............................................................................48! Additives in Bread Models ..........................................................................................49! Antioxidants.................................................................................................................49! Fatty Acids...................................................................................................................50! Fiber.............................................................................................................................50! Diet and Health Effects................................................................................................52! Supplementation ..........................................................................................................52! Functional Foods .........................................................................................................56! Summary......................................................................................................................57! Chapter 3: Chemical Composition and Health Properties of the Selected Cold-Pressed Grape Seed Flours and Oils .........................................................................................59! Introduction..................................................................................................................59! Materials and Methods ................................................................................................61! Materials and Chemicals..............................................................................................61! Lipid Extraction...........................................................................................................61! Antioxidant Extraction.................................................................................................62! Fatty Acid Composition...............................................................................................62! Carotenoid/Tocopherol Composition ..........................................................................63! Total Phenolic Content ................................................................................................64! iv Oxidative Stability Index (OSI)...................................................................................64! Oxygen Radical Absorbance Capacity (ORAC) Assay...............................................65! Hydroxyl Radical Scavenging Capacity (HOSC) Estimation .....................................65! DPPH˙ Scavenging