Understanding the development of color and color stability of dark cutting beef based on mitochondrial proteomics

Label-free proteomics was applied to understand the color and color stability development of dark cutting beef (DC). The color traits of DC (pH = 6.86) and normal beef (pH = 5.49) were determined during 7 days of display. DC had a lower redness and greater color stability, which was attributed to its higher deoxy-myoglobin content, greater oxygen consumption, as well as higher metmyoglobin reducing activity and lower lipid oxidation. A total of 28 differentially expressed mitochondrial proteins (fold change >1.8) between the two groups were identified, with 21 proteins overexpressed in DC mainly involved in oxidative phosphorylation, generation of reducing equivalent, TCA cycle and chaperones. These enhance the level of mitochondrial respiration, the stability of reducing MetMb and myoglobin and mitochondria function, leading to color characteristics of DC. Moreover, Glutaryl-CoA dehydrogenase was for the first time reported to be significantly associated with color parameters and its direct relationship with meat color is worthy investigation.