LYSOSOMAL INTEGRITY IN POSTMORTEM BOVINE SKELETAL-MUSCLE

Post mortem aging of bovine skeletal muscle was found to result in los s of lysosomal integrity when assessed by biochemical and ultrastructu ral means. However, after aging to 14 days, the non-sedimentable beta- glucuronidase activity was only slightly higher than that at slaughter . Similarly, total non-sedimentable cathepsin D activity increased onl y slightly. Specific activity of cathepsin D increased, perhaps throug h proteolytic activation. Ultrastructural examination revealed that me mbrane integrity decreased substantially post mortem. These results su ggest that a portion of the lysosome's enzyme content was released in response to normal aging and thus could participate in changes in meat texture post mortem.