title: Postmortem metabolic rate and calpain system activities on beef longissimus tenderness classifications.
abstract: In this study, we adopted a model of tenderness classification in order to determine the factors affecting the tenderness and tenderization characteristics of beef longissimus, using cluster analysis on the basis of Warner-Bratzler shear force and myofibril fragmentation index, at 1, 7, and 14 d. The rate of tenderization was effectively differentiated by pH, R-values, mu-calpain activity, and calpastatin activity. Differences among tenderness classes were generally detected at 3 and 9 h postmortem for metabolic rate, and at 9 and 24 h for the activities of mu-calpain and calpastatin. Early postmortem metabolic rate and calpain system activities were verified as important factors with regard to longissimus tenderization.
authors.affiliation: Division of Food Science, College of Life and Environmental Sciences, Korea University, Seoul, South Korea.
authors.forename: Min-Suk
authors.initials: MS
authors.lastname: Rhee
authors.forename: Youn-Chul
authors.initials: YC
authors.lastname: Ryu
authors.forename: Byoung-Chul
authors.initials: BC
authors.lastname: Kim
mesh_terms: D000818:Animals; D002135:Calcium-Binding Proteins / Q000032:analysis; D002154:Calpain / Q000032:analysis*; D002417:Cattle; D016000:Cluster Analysis; D008461:Meat Products / Q000032:analysis* / Q000145:classification*; D009210:Myofibrils / Q000378:metabolism; D011180:Postmortem Changes
chemical_list: D002135:Calcium-Binding Proteins; C033668:calpastatin; D002154:Calpain