Differential characteristics of meat flavor compounds, colonic microbiome and metabolome between Duroc × Landrace × Yorkshire pigs with high and low intramuscular fat of longissimus dorsi muscles.

Pork flavor has received widespread attention from consumers and producers, but the flavor differences and microbial differences in pigs with different intramuscular fat (IMF) content remain unclear. This study aimed to investigate differential characteristics of meat flavor compounds, colonic microbiome and metabolome between Duroc × Landrace × Yorkshire pigs with high and low IMF using multi-omics analyses. High IMF (H-IMF) pork had higher marbling scores, tenderness, and overall acceptability than low IMF (L-IMF) pork. The overall flavor profiles were similar between H-IMF and L-IMF pork. The main enriched volatile flavor compounds (VOCs) in H-IMF pork belonged to esters and were mainly represented by 3-methylbutanal, ethyl acetate, (E)-2-decenal, ethyl nonanoate, 2-nonanone, methional, and ethyl decanoate. Dorea was significantly enriched and showed a positive correlation with main VOCs, whereas Treponema, Alloprevotella, and Cryptobacteroides were significantly reduced in the colon of H-IMF pigs. Differential metabolites were mainly enriched in nucleotide and pyrimidine metabolic pathways. Dorea and metabolites cytidine, 2'-deoxycytidine-5'-monophosphate, and 2'-deoxythymidine-5'-monophosphate participated in nucleotide and pyrimidine metabolic pathways and potentially influenced the production of flavor compounds. Overall, the results imply that IMF influences pork flavor compounds and is closely associated with the gut microbiota, indicating potential to improve flavor attributes through microbial regulation.