Contribution of mitochondria to postmortem muscle tenderization: a review.

ABSTRACT

Postmortem meat tenderization is a process mediated by a series of biochemical reactions related to muscle cell death. Cell death is considered a sign that muscle has started to transform into meat. Mitochondria play a significant role in regulating and executing cell death, as they are an aggregation point for many cell death signals and are also the primary target organelle damaged by tissue anoxia. Mitochondrial damage is likely to have an expanded role in postmortem meat tenderization. This review presents current findings on mitochondrial damage induced by the accumulation of reactive oxygen species during postmortem anaerobic metabolism and on the impact of mitochondrial damage on proteolysis and discusses how this leads to improved tenderness during aging. The underlying mechanisms of mitochondrial regulation of postmortem muscle tenderization likely focus on the mitochondria's role in postmortem cell death and energy metabolism. The death process of postmortem skeletal muscle cells may exhibit multiple types, possibly involving transformation from autophagy to apoptosis and, ultimately, necroptosis or necrosis. Mitochondrial characteristics, especially membrane integrity and ATP-related compound levels, are closely related to the transformation of multiple types of dead postmortem muscle cells. Finally, a possible biochemical regulatory network in postmortem muscle tenderization is proposed.