Uncovering potential relationships between flavor compounds and bacteria, lipids, metabolites in shrimp paste: A...

Shrimp paste is commonly produced by spontaneous fermentation, resulting in substantial variation in flavor quality. However, the associations linking bacterial communities, non-volatile flavor precursors, and volatile compounds remain insufficiently understood. In this study, flavoromics, microbiomics, lipidomics, and metabolomics were integrated to characterize seven commercially available shrimp paste products and explore potential cross-omics relationships related to flavor formation. Aldehydes and sulfur- and nitrogen-containing compounds were identified as major potential contributors to the characteristic aroma of shrimp paste. Tetragenococcus, Acinetobacter, and Peptostreptococcus were identified as prevalent bacterial genera across the samples. Differential lipids and metabolites were mainly associated with linoleic acid metabolism and glycine, serine, and threonine metabolism. Cross-omics correlation analysis indicated that these bacterial genera were associated with free fatty acids, L-alanine, D-alloisoleucine, and several potential aroma-active compounds. Betaine and creatine were also associated with sulfur- and nitrogen-containing volatile compounds, suggesting that they may serve as potential flavor precursors that can be converted into flavor compounds. Overall, this study provides preliminary cross-omics insights into the associations among bacterial communities, lipids, metabolites, and volatile compounds in commercial shrimp paste, and identifies candidate bacterial taxa and metabolic precursors that may serve as potential markers for flavor quality evaluation. These findings provide preliminary insights for the development of standardized flavor assessment strategies and prioritize potential targets for subsequent validation under controlled fermentation conditions.