Flavor characterization of pork cuts in Chalu black pigs using multi-omics analysis

The study investigated the flavor variations in four different fresh pork cuts (longissimus thoracis, LT; trapezius muscle, TM; hamstring muscle, HM; Pork Belly, PB) from Chalu black pigs (ten castrated boars) using multi-omics techniques. The research also explored the influence of muscle fiber type on the flavor profiles of these cuts. Results from quantitative real-time PCR (qRT-PCR) indicated significant differences in muscle fiber type across the four pork cuts in various anatomical locations. Each cut exhibited distinctive volatile organic compounds (VOCs) profiles, with HM displaying a sweet and fruity green flavor, LT showcasing a fatty and nutty taste, PB presenting a fresh, citrusy, and green flavor, and TM offering a floral and bitter note. Variations in fatty acid carbon number and saturation were observed among the cuts, with HM, LT, and PB being rich in fatty acids with C16-18, C19-21, and 3 double bonds, respectively. The metabolites specific to each cut were found to play key roles in different metabolic pathways, such as protein-related pathways for HM, arginine biosynthesis for LT, lysine biosynthesis for PB, and D-arginine and D-ornithine metabolism for TM. Differentially expressed genes (DEGs) were associated with amino acid metabolism for HM, glycolysis/gluconeogenesis for LT, and cellular aromatic compound organization for PB. Notably, HM and PB displayed unique flavor characteristics, while TM exhibited relatively neutral features. The study also identified correlations among VOCs, muscle fiber type, lipids, metabolites, and gene patterns specific to each cut, highlighting the complex interplay of factors influencing pork flavor.