Myofibrillar 1-D fingerprints and myosin heavy chain MS analyses of beef loin at 36 h postmortem correlate with tenderness at 7 days.

This study investigated the potential for relating changes in electrophoretic protein patterns derived from the longissimus dorsi of beef cattle 36 h postmortem with tenderness at 7 days. We report finding a significant correlation (R(2)=0.82) between electrophoretic l. dorsi myofibrillar fingerprints at 36 h postmortem and tenderness at 7 days, as determined by Warner-Bratzler shear analysis. In addition, we have used mass spectrometric analyses to identify fragments of bovine myosin heavy chain that are significantly correlated with tenderness. Furthermore, this method offers the potential to increase our understanding of the fundamental cellular mechanisms underlying the proteolytic breakdown of muscle proteins during the aging process.