Fragmentation of loin steaks from U.S. commercial and U.S. utility beef carcasses

Short loin steaks were removed from U. S. Commercial (n=38) and U. S. Utility (n=42) beef carcasses to facilitate study of cooked meat tenderness as related to certain raw muscle fragmentation measures, carcass traits and laboratory procedures. Carcass traits explained 14.1 percent of the variation in shear force value while all fragmentation measures accounted for 61.1 percent. Frozen fragmentation measures (R² X 100 = 58.1 percent) were superior to fresh fragmentation measures (R² X 100 = 37.3 percent). Results indicate that fresh or frozen fragmentation index of raw muscle is superior to selected carcass traits and/or laboratory assays. The best regression model (two fragmentation measures) accounted for 56.6 percent of the variation in tenderness.