The overall objective of the proposed research is to delineate the role of mitochondria in modulating postmortem metabolism and meat shelf stability during storage and display. We will accomplish the overall research objective by pursuing the following specific aims: 1. Investigate the role of mitochondria in modulating the rate of postmortem metabolism and pH decline in pork; 2. Determine the contribution of mitochondria-mediated oxidative stress to beef color stability during retail display; 3. Determine metabolic differences between muscles varying in mitochondrial content, rate of pH decline, and color stability using untargeted metabolomics profiling.