Insights into volatile substance changes of tilapia fillets before and after steaming and boiling during refrigeration based on metabolomics

This study investigated the key volatile substances using SPME-GC–MS and metabolites using LC-MS, as tilapia fillets before and after steaming and boiling during refrigeration. Results indicated untreated, steamed, and boiled tilapia fillets post-refrigeration exhibited 15, 22, and 23 key volatile substances, respectively, primarily aldehydes, alcohols, and ketones. 97, 70, and 67 differential metabolites were identified by PLS-DA, respectively. The predominant differential metabolites were categorized as lipid and lipid-like molecules (34, 28, 29), organic acids and derivatives (18, 7, 10), and nucleosides, nucleotides, and analogs (8, 8, 10). In untreated, steamed and boiled tilapia fillets post-refrigeration, 13, 15 and 10 key volatile substances respectively showed positive correlations with lipids and lipid-like molecules. Amino acid, lipid, and nucleotide metabolism were identified as potential metabolic networks for key volatile substances production. These findings provide a theoretical foundation for optimizing high flavor quality processing and culinary applications of refrigerated fish products.