Changes in Chicken Muscle Proteins During Cooking and Subsequent Frozen Storage, and Their Significance in Quality

SUMMARY Cooking of chicken broilers destroyed the proteolytic activity and the buffer extractability of muscle proteins, and decreased the sulfhydryl‐group content of muscle proteins by about 50%. During frozen storage of cooked meat for two years at temperatures between −10 and −40°C, neither the formation of protein‐breakdown products nor the development of detectable off‐odor occurred. The sulfhydryl‐group content of muscle tissue decreased gradually, showing a relation with storage time and loss of tenderness. Results suggest that the color reaction between the sulfhydryl groups of muscle tissue and nitroprusside may be useful as an index of quality changes in precooked frozen poultry.