Insights into protein degradation-related volatile substances changes in tilapia fillets (Oreochromis niloticus) during storage at 4 °C based on astral DIA proteomics and flavoromics

The aim of this study was to investigate the generation pathways of volatile substances derived from protein degradation in tilapia fillets stored at 4 °C, using Astral DIA proteomics. Seventeen key volatile substances were identified using HS-SPME-GC–MS. Among them, five substances were further recognized by the PLS-DA model as potential markers for sample classification. Differentially expressed proteins were primarily enriched in the Proteasome, Ribosome, and Oxidative phosphorylation pathways. Pearson correlation analysis and KEGG enrichment analysis suggested that major metabolic pathways, including Ribosome, Oxidative phosphorylation, and Neuroactive ligand-receptor interaction, may be associated with the formation of twelve key volatile substances, such as trimethylamine and nonanal, through protein degradation and the regulation of energy and lipid metabolism. A potential metabolic pathway map was constructed for amino acid, lipid, nucleotide, and carbohydrate metabolism. This study expands the theoretical understanding of volatile substances formation from protein degradation and provides insights into the regulation of protein degradation and flavor quality during refrigerated storage. • Five potential classification marker volatile substances were identified by PLS-DA. • Proteasome, ribosome and oxidative phosphorylation are the key degradation pathways. • Proteasome, cytochrome c oxidase, etc. lead to apoptosis and protein degradation. • Protein degradation, energy, and lipid metabolism affect production of key volatiles. • Enzymes in metabolism of amino acid, lipid, etc. promote generation of key volatiles.