Age-driven marbling in Haimen goat meat: multi-omics dissection of lipid/amino signatures and IMF regulatory networks

Elevated intramuscular fat (IMF) deposition is widely recognized as a hallmark of high-grade meat with improved sensory and nutritional properties. Thus, in the current study, the physicochemical and nutritional trajectories of Haimen goat meat slaughtered at different stages were systematically characterized. High-IMF (HF) and low-IMF (LF) were further dissected by lipidomics and amino-acid profiling to resolve fatty-acid and amino-acid signatures. IMF exhibited linear accretion with age. The HF group exhibited significantly higher proportions of SFA, MUFA and n-3/n-6 PUFA, concomitant with enhanced concentrations of essential and flavor-active amino acids. Proteomics analysis identified key regulatory genes related to intramuscular fat deposition including ECI1, HADH, and ACO2, highlighting the core roles of acetyl-CoA and succinyl-CoA in lipid metabolism. Overall, these results suggest that high-IMF goat meat may represent a nutrient-dense functional food source.