Postmortem changes in sarcoplasmic proteins associated with color stability in lamb muscle analyzed by proteomics

The aim of this research was to correlate the postmortem changes of sarcoplasmic proteins with instrumental color and various biochemical parameters relating to color attributes. Two-dimensional electrophoresis was used to investigate sarcoplasmic protein changes in cardiac muscle during refrigerated storage. Eleven differentially abundant protein spots were identified between storage time at day 1 and day 5 (P < 0.05). The functional category of proteins consisted of metabolic enzymes, binding proteins, chaperone proteins, and antioxidant proteins. These proteins demonstrated positive correlation with a*-value (creatine kinase M-type and malate dehydrogenase), metmyoglobin-reducing activity (aconitate hydratase, creatine kinase, and thioredoxin-dependent peroxide reductase), tissue oxygen consumption rate (creatine kinase and malate dehydrogenase), and mitochondrial respiration control ratio (thioredoxin-dependent peroxide reductase and mitochondrial superoxide dismutase). The protein patterns were likely to have impact on postmortem metabolism, thereby protecting muscle against discoloration.