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Influence of Storage Temperature on Changes in Frozen Meat Quality

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Influence of Storage Temperature on Changes in Frozen Meat Quality Influence of Storage Temperature on Changes in Frozen Meat Quality Thesis Presented in Partial Fulfillment of the Requirements for the Degree Master of Science in the Graduate School of The Ohio State University By Jeffrey Caminiti Graduate Program in Food Science and Technology The Ohio State University 2018 Thesis Committee Dennis Heldman, Advisor Macdonald Wick, Advisor Christopher Simons 1 Copyrighted by Jeffrey T. Caminiti 2018 2 Abstract Food is often frozen to prolong shelf-life by maintaining safety and high quality. Since frozen food storage is energy intensive, careful evaluation of the influence of storage temperature on shelf-life is needed. Although the shelf-life of frozen meat at - 18°C may be desirable, the influence of slightly higher storage temperatures on shelf-life have not been thoroughly investigated. Through the understanding of quality degradation reactions and their dependence on temperature, an argument may be made to encourage storage at a more sustainable temperature. The objective was to evaluate the effect of storage temperature on frozen chicken and ground beef quality attributes to identify improved energy efficiencies during storage. Whole muscle chicken breasts (pectoralis major) were frozen to -20°C [-4°F] then stored at -10°C [14°F], -15°C [5°F], or -20°C for one year. In a completely randomized design monthly quality testing was conducted on three replicates thawed overnight to 4°C. Quality analysis consisted of % drip loss measurements, water holding capacity (WHC), moisture content (WBMC), lipid oxidation by 2-thiobarbituric acid assay (TBARS), color, and cooked texture analysis by Blunt Meullenet-Owens Razor Shear (BMORS). Differences in temperature conditions across time were observed in % drip loss, WHC, L*a*b*, and BMORS (p<0.05). The creation of a shelf-life prediction model based on % drip loss results can be used to assess risk to processors considering ii increasing storage temperatures. This study has shown the potential energy savings may be accomplished without dramatic losses in quality by increasing storage temperatures modestly. In a completely randomized study 297 ground beef experimental units consisting of 90 patties were packaged in one of three ways then frozen to -22°C . Packaging included: plastic overwrap; a high oxygen permeability package, OTR <0.1 cc/100 in2/day; and a low oxygen permeability package, OTR <0.05cc/100in2/day. The units were later distributed to one nine chest freezers stored at -10°C [14°F], -15°C [5°F], or - 20°C for one year. Color in the L*a*b* color space and lipid oxidation via TBARS were collected monthly. Prior to analysis, meat was thawed at 4°C for 24 hours. Shelf-life was not improved from improved packaging. Statistically the barriers were used as additional replications for a robust analysis of temperature. The change in redness (a*) over time followed second order rate kinetics. Arrhenius activation energy for a* change was calculated to be 122.3 kj/mol. TBARS data was fit to a modified Gompertz model (R2=0.91). Predicted maximum TBARS was dependent on temperature and greatest under -10°C, followed by -15°C, and -20°. The state and availability of the unfrozen water may play a role in maximum TBARS observation. Similar rates in the colder temperatures provide an opportunity to reevaluate storage conditions for high-fat products Observations made on whole muscle chicken and ground beef indicate potential energy savings during frozen storage. The models produced show the measurable reduction in quality would be only minor due to small increases in storage temperature. iii Due to apparent asymptotes and non-Arrhenius rate constants future work must involve a wide range of storage temperatures for the development of empirical models as a function of temperature iv Acknowledgments A special thanks to my parents and brothers, your continued support throughout my education has been everything. My years of school have been full of unexpected challenges; I would not have made it this far without your love and guidance. Thank you to The Ohio State University department of Food, Science, and Technology as well as the department of Animal Sciences. The education I have received through my time at this university has been incredibly valuable. The facilities and opportunities available are greatly appreciated. I want to thank my committee: Dr. Dennis R. Heldman, Dr. Macdonald Wick, Dr. Christopher Simons. Your support and expertise before and during my master’s work have been invaluable. You have all helped me hone my interests in scientific pursuits. I am especially grateful for the generosity of Dale A. Seiberling to the Food Engineering Research Laboratory at The Ohio State University for providing a home to my research project. A special thanks is owed to David M. Phinney and John Frelka for sharing knowledge in and out of the laboratory that became crucial to my success. Without David and John, the difficult timeline involved in these 12-month studies would not have been possible. Furthermore, Dr. John Frelka’s successful proposal and the Ohio Agricultural Research and Development Center SEEDS program have made this research a v reality. A final thanks to the livestock and the generous industry suppliers of the copious amount of meat samples used in these studies. vi Vita 2011................................................................Elder High School 2014, 2015......................................................Internship, Perfetti van Melle 2016................................................................B.S. Food Science, Ohio State University 2017 to present ...............................................Graduate Research Associate, Department of Food, Science, & Technology, The Ohio State University Fields of Study Major Field: Food, Science, & Technology vii Table of Contents Abstract ............................................................................................................................... ii Acknowledgments............................................................................................................... v Vita .................................................................................................................................... vii List of Tables .................................................................................................................... xii List of Figures .................................................................................................................. xiii Chapter 1. Introduction ....................................................................................................... 1 1.1 Objectives: ................................................................................................................ 3 1.2 References: ................................................................................................................ 4 Chapter 2. Review of Literature.......................................................................................... 6 2.1 Phenomena of sub-freezing water in food ................................................................ 6 2.1.1 Unfrozen water content in food ......................................................................... 6 2.1.2 Recrystallization in frozen foods ....................................................................... 7 2.1.3 Glass transitions state ......................................................................................... 7 2.2 Water holding capacity in muscle foods: measurements and deterioration .............. 9 2.2.1 Water holding in meat processing (yield and freezing rate) .............................. 9 2.2.2 Mechanisms in water holding. ......................................................................... 11 2.2.2 Other methods of measuring water holding ..................................................... 12 2.3 Color loss in meats: sensory considerations, measurements, mechanisms, & kinetics .......................................................................................................................... 12 2.3.1 Color perception and consumer acceptance ..................................................... 12 2.3.2 Instrumental measurement of color ................................................................. 13 2.3.3 Myoglobin oxidation kinetics effects on meat color ........................................ 14 2.4 Texture analysis of chicken breasts ........................................................................ 16 2.5 Lipid oxidation: mechanisms, history, and detection methodologies ..................... 19 2.5.1 Lipid oxidation Introduction & reaction progression ...................................... 19 2.5.2 Past reviews of lipid oxidation in meat research ............................................. 22 2.5.3 Detection of quantification of lipid oxidation in meat ..................................... 23 2.5.4 TBARS history and distillation method development ..................................... 24 2.5.5 TBARS extraction method development ......................................................... 27 viii 2.5.6 Applications of TBRS in meat quality research .............................................. 28 2.6 Extended shelf-life studies of meat: ........................................................................ 29 2.7 Magnetic Resonance Imaging (MRI) as a tool for meat analysis ........................... 33 2.8 References: .............................................................................................................
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