Revealing the correlation between small molecule metabolites, volatile compounds and microbial communities during the ripening of Xuanwei ham

To elucidate the impact of microorganisms on the metabolites and flavor of Xuanwei ham, the correlation between volatile compounds, small molecule metabolites, and microbial communities in Xuanwei ham was studied. The results showed that the predominant bacteria and fungi were Proteobacteria , Firmicutes , and Ascomycota , respectively at the phylum level, and the main bacteria was Staphylococcus , and the predominant fungi was Aspergillus at the genus level. A total of 48 differential metabolites were screened, and amino acids were the most abundant. Upon pathway analysis, 21 metabolic pathways were found to be related to ham ripening. More than 20 key metabolites such as arginine were accurately matched by Public Chemistry Database (Pub Chem) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Eighteen volatile flavor characteristic compounds were identified, and the relative content of acetone in ham samples from various years was the highest. Additionally, the findings explored the relationship between small molecule metabolites, volatile compounds, and microorganisms in Xuanwei ham, which showed that the microorganisms in the samples had a positive effect on a variety of amino acids and alcohols. The findings represent a fertile ground for the formation of ham quality. • The predominant bacteria and fungi were Proteobacteria , Firmicutes , and Ascomycota in Xuanwei ham, respectively. • Fermenting-ripening of Xuanwei ham was related to twenty-one metabolic pathways. • Twenty-three key metabolites including L-arginine and L-aspartic acid were accurately matched through KEGG and Pub Chem. • A variety of aldehydes and amino acids have a significant positive correlation with microorganisms. • Microorganisms generate an unequal effect in the formation of flavor and metabolites in Xuanwei ham.