Factors Associated with the Tenderness of Three Bovine Muscles

Abstract

ABSTRACT Samples were obtained from bovine Longissimus dorsi (L), Biceps femoris (BF) and Psoas major (PM) muscles at different times of postmortem storage at 1.2°C. At day 1 postmortem, PM was the most tender muscle followed by BF then L; PM muscle also had the smallest fiber area and longest sarcomere followed by BF and L. After postmortem storage, shear force values decreased greatly for L, and only slightly for PM. There were no differences in activities of cathepsins, B, H, and L for any of the muscles. However, L muscle had the highest Ca ++ ‐dependent protease activity followed by BF and PM. Thus results suggested that Ca++‐dependent protease activity was best determinant of tenderization resulting from postmortem storage at refrigerated temperatures.