Lactylation of muscle proteins is associated with meat quality traits in MSTN‐mutated cattle on rigor mortis

Abstract BACKGROUND Rigor mortis is a complex biochemical process in the conversion of muscle to meat and results in an increase in the toughness of the meat during the early post‐mortem period. The mechanism of rigor mortis, particularly in myostatin (MSTN) mutant‐type (MT) beef, remains to be elucidated. RESULTS Here, we investigated the pH of different wild‐type (WT) and MT muscles during the early post‐mortem period and showed that the ultimate pH of WT meats is reached at 48 h post mortem and that of MT at 12 h post mortem. Furthermore, meat quality traits, including color, shear force and water holding capacity, and protein lactylation were measured at 12 h post mortem. In particular, we showed that the total levels of lactylated proteins in longissimus dorsi, tenderloin, sirloin and semitendinosus muscles is positively correlated with shear force, pressing loss and cooking loss, whereas in shank muscles there is no significant relationship between lactylation and meat quality traits. CONCLUSION The present study uncovers a novel epigenetic modification involved in rigor mortis of MSTN‐mutated beef and provides more insights into the post‐mortem meat aging. © 2025 Society of Chemical Industry.