The Effect of µ/m‐Calpain on Protein Degradation of Chicken Breast Meat.

This study was designed to determine the effects of µ/m‐calpain on the degradation of cytoskeletal proteins in pectoralis major. Four chickens were slaughtered and the breasts were removed and stored for 12 hr at 4 °C. Each sample was divided into three groups and respectively immersed in control reagent, calpain inhibitor, and caspase inhibitor at 4 °C. The samples were used to evaluate troponin‐T and desmin degradation, calpain activity, and myofibril ultrastructure at 12 hr, day 1, day 3, and day 7. Casein zymography revealed that µ‐calpain could not be detected in all samples after 12 hr postmortem. The calpain inhibitor inhibited µ/m‐calpain activity and reduced troponin‐T and desmin degradation during 7 day postmortem. The caspase inhibitor inhibited µ/m‐calpain activity and, troponin‐T and desmin degradation before day 3 postmortem. The findings suggest that, µ/m‐calpain had an effect on cytoskeletal protein degradation after 12 hr postmortem. [ABSTRACT FROM AUTHOR]