University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Theses and Dissertations in Animal Science Animal Science Department 7-2012 Mechanism and Control of Beef Toughening during Retail Display in High Oxygen Modified tmospherA e Packages Lasika S. Senaratne University of Nebraska-Lincoln, [email protected] Follow this and additional works at: https://digitalcommons.unl.edu/animalscidiss Part of the Other Animal Sciences Commons Senaratne, Lasika S., "Mechanism and Control of Beef Toughening during Retail Display in High Oxygen Modified tmospherA e Packages" (2012). Theses and Dissertations in Animal Science. 54. https://digitalcommons.unl.edu/animalscidiss/54 This Article is brought to you for free and open access by the Animal Science Department at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Theses and Dissertations in Animal Science by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. MECHANISM AND CONTROL OF BEEF TOUGHENING DURING RETAIL DISPLAY IN HIGH OXYGEN MODIFIED ATMOSPHERE PACKAGES by Lasika Shyamalie Senaratne-Lenagala A DISSERTATION Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Doctor of Philosophy Major: Animal Science Under the Supervision of Professor Chris R. Calkins Lincoln, Nebraska August, 2012 MECHANISM AND CONTROL OF BEEF TOUGHENING DURING RETAIL DISPLAY IN HIGH OXYGEN MODIFIED ATMOSPHERE PACKAGES Lasika Shyamalie Senaratne-Lenagala, Ph.D. University of Nebraska, 2012 Advisor: Chris R. Calkins This research was conducted to elucidate the mechanism and factors (diet, aging time, antioxidant level, and retail display time) affecting beef toughening in retail display under high oxygen atmosphere packages (HiOx-MAP; 80% O2 and 20% CO2). In the first study, effects of HiOx-MAP on color and lipid stability of beef m. longissimus lumborum steaks from yearlings fed corn or 30% wet distillers grains plus soluble (WDGS) diets supplemented with (150 mg/kg) or without (0 mg/kg) AGRADO-PLUS (AG) antioxidants were studied. Steak color-shelf life was extended (P < 0.0001) by HiOx- MAP compared to oxygen permeable film packages (PVC-OW). Steaks from corn+AG- supplemented cattle had (P ≤ 0.05) less discoloration and lower lipid oxidation levels at the end of retail display than steaks from all other diets. However, effects of AG on reducing steak discoloration and lipid oxidation when feeding WDGS could not be seen (P > 0.05). In the second study, mechanism and factors affecting beef toughening due to HiOx-MAP during retail display were investigated. High oxygen atmosphere packages oxidized proteins (P < 0.10) and formed protein aggregates (P = 0.01) thereby making steaks tougher (P <.0001). Also, HiOx-MAP reduced (P = 0.001) troponin-T degradation in beef. Protein aggregates were formed mainly by polymerization of myosin proteins mostly due to disulfide bonds. Retail display of steaks aged long-term increased protein oxidation (P <.0001) and polymerization (P < .0007), thereby making beef tougher (P < 0.06). Feeding WDGS also increased protein oxidation (P = 0.002) and polymerization (P < 0.07); however, tenderness was improved (P = 0.06). Dietary supplementation of AG toughened beef due to protein oxidation (P < 0.04) and decreased (P = 0.001) proteolysis by decreasing (P = 0.007) sarcoplasmic free-calcium levels. In the third study, tenderness and protein oxidation gradient in the beef m. triceps brachii roasts were studied. Protein oxidation, aggregation, and toughening occurred at a descending gradient from the outside to the inside of beef roast packaged in HiOx-MAP systems (P < .0001). iv ACKNOWLEDGEMENTS Earning a Ph.D. degree is probably the most challenging and enthusiastic accomplishment in the first 34 years of my life. It has been a great privilege to spend several years in the Department of Animal Science at the University of Nebraska-Lincoln and all its members and memories gathered will always remain cherished in my heart…!! Foremost, I would like to thank my supervisor, Dr. Chris Calkins, who has given great scholastic support and shared his expertise and research insight with me for the last five years. I am indebted to him for giving me a golden opportunity to pursue a Ph.D. in Meat Science and Muscle Biology, an area in which I was passionate about since I was an undergraduate. I am deeply grateful to him for sharing a wealth of expertise and insight in Meat Science research and dedicating his valuable time, guidance and directives for me to be fruitful in research. Also, I would like to express my sincere gratitude and appreciation to my Ph.D. supervisory committee, Drs. Madhavan Soundararajan, Steven Jones, and Timothy Carr, for providing me an excellent support whenever it was needed. I must also thank to Drs. Roger Mandigo, Dennis Burson, and Gary Sullivan in the Department of Animal Science for educating me about fascinating facts of meat science during my stay in the graduate school. I would like to thank Tommi Jones, who provided invaluable support in laboratory works, Sherri Pitchie for helping me on numerous occasions and for always being there for me, and Calvin Schrock for arranging things in the meat lab every time, even after a short notice. v My deepest gratitude also goes to all the present and past graduate students in the department of Animal Science who I came across with during my graduate program. Among them, I highly appreciate the invaluable and unselfish support I received from Amilton Souza de Mello Jr., Kim Varnold, Siroj Pokharel, Justine Hosch, Jeremey Hinkle, Jerilyn Hergenreder, Michelle Semler, Justin Moore, Derek Schroeder and Michael Chao. I am thankful to Ranjith Ramanathan at the University of Kentucky, and Rebecca Cederberg and Yoshitha Wanniarachchi in the department of Animal Science for giving their valuable time and help whenever I needed. I am also very thankful to the Novus International Inc., for funding in part for this research. I would like to express my sincere debt of gratitude to my undergraduate advisor and my mentor Prof. H. W. Cyril at the University of Peradeniya, Sri Lanka for identifying my potentials and directing me to the truly fascinating field of meat science. Special thanks should also go to the faculty in the department of Animal Science at the University of Peradeniya, Sri Lanka for the guidance I received to be successful in life. Finally, I would like to express my eternal gratitude to my ever loving mother and sister for bringing sunshine into my life when all else failed. Also, I would like to extend my heartfelt thanks to Roshan for his unconditional love, care and emotional support for the last few years. Last but not least, I wish to dedicate my PhD dissertation to my beloved father who is the angel that has been constantly watching over me since he left us 18 years ago. vi TABLE OF CONTENTS ABSTRACT ....................................................................................................................... ii ACKNOWLEDGEMENTS ............................................................................................ iv TABLE OF CONTENTS ................................................................................................ vi INTRODUCTION..............................................................................................................1 LITERATURE REVIEW .................................................................................................4 High oxygen modified atmosphere packaging .................................................................5 Effects of high oxygen atmosphere packages on muscle food quality ...............................5 Color stability ...............................................................................................................5 Lipid stability and off-flavor ........................................................................................8 Juiciness ......................................................................................................................10 Nutritional quality ......................................................................................................13 Tenderness ..................................................................................................................15 Mechanism of protein oxidation .....................................................................................17 Formation of carbonyls...............................................................................................19 Loss of sulfhydryl or free-thiol groups .......................................................................20 Protein cross-linking ...................................................................................................21 Oxidation of myofibrillar proteins .................................................................................22 Oxidation of proteases ....................................................................................................23 Calpains ......................................................................................................................23 Oxidation of calpains ..................................................................................................25 Controlling strategies against protein oxidation .............................................................26 vii Dietary strategies ........................................................................................................26