Glycogen and other glucose-related metabolites are mobilized into glycolysis as energy substrates , resulting in lactate accumulation and subsequent pH decline . Consequently, many cytosolic and myofibrillar proteins, such as enolase, troponin T, and desmin, are exposed to acidic denaturing environments. Neutral proteases, calpains, are activated by Ca 2+ released from the dysregulated sarcoplasmic reticulum, while caspases also participate in the postmortem degradation of muscle cell proteins . Muscle protein degradation is thought to contributes to postmortem meat tenderization and the generation of flavor component precursors, such as AAs and peptides .