Different phenotypic and proteomic markers explain variability of beef tenderness across muscles

This study analyzed the abundance of 24 different proteins, tenderness biomarkers, and 11 phenotypic carcass characteristics and muscle properties. This was done on 111 samples of two muscles, Longissimus thoracis (LT) and Semitendinosus (ST) from the Charolais bovine breed. The strategy was to constitute three classes of tenderness on the two muscles separately on the shear-force data (Warner-Bratzler). Then we tested which proteins or phenotypic characteristics explained this classification. Results showed that tenderness classes of ST muscle were well-explained by 12 proteins and 6 phenotypic characteristics. However, for LT muscle the classification could only be explained by 7 phenotypic characteristics. This demonstrates that in ST and LT the variability of beef tenderness is explained by different factors. In ST muscle, the main results of this study demonstrated the importance of Heat Shock Proteins such as Hsp27 (P = 0.002) and the oxidative stress protein: PRDX6 (P = 0.003). We also confirmed the role of Enolase 3, involved in glycolytic metabolism (P = 0.003), and contractile protein such as MyHC IIx (P = 0.028)