Comparative proteomics to reveal muscle-specific beef color stability of Holstein cattle during post-mortem storage

- Proteome differences in LL and PM during storage were analyzed by label-free MS.
- Results of color traits indicated that LL showed better color stability than PM.
- Overabundant proteins with roles of antioxidation, protection, and repair in LL.
- Proteins involved in TCA cycle and mitochondrial ETC were overabundant in PM.

Label-free strategy was applied to elucidate muscle-specific beef (M. longissimuss lumborum (LL) and M. psoas major (PM)) color stability of Holstein cattle during post-mortem storage at 4 °C ± 1 °C. LL showed greater (p < 0.05) redness (a∗) value than PM at day 4 and 9 storage, while the proportion of metmyoglobin in PM exhibited a greater increase than in LL muscle. Furthermore, an overabundance of proteins with the functions of antioxidation, protection, and repair in LL were conducive to its color stability, whereas the overabundant proteins/subunits involved in tricarboxylic acid (TCA) cycle and mitochondrial electron transport chain (ETC) in PM indicated greater oxidative metabolism and degradation of ETC complexes, resulting in poor color stability. Bioinformatic analyses indicated that these proteins mainly participated in oxidation-reduction processes, TCA cycle, and ETC processes. All of these results provided a deeper understanding of muscle-specific beef color stability from the perspective of proteomics.