Dynamic changes of volatile compounds and small molecule compounds during curing and drying processes of Megalobrama amblycephala

In this study, the changes in volatile compounds, lipids, and small molecule compounds during the curing and drying processes were examined. The results showed that lipid oxidation was enhanced during curing and drying processes. A total of fifty-two types of volatile compounds in the dry-cured fish were detected, and the contents of alcohols (such as 3-methyl-1-butanol, 1-octen-3-ol), ketones (such as 2-heptanone, 2-octanone), and aldehydes (such as 3-methylbutyraldehyde, hexanal, nonanal, decanal) were increased during curing and drying processes. A total of 812 metabolites were identified. The metabolites in linoleate, arachidonate, nucleotide, amino acid, and other metabolic pathways showed significant differences between drying stage and curing stage. The oxidative degradation of arachidonate acid, linoleate acid, and amino acid may contribute to the changes in volatile compounds during the curing and drying stages. Seven compounds including shikimic acid, carnitine C5: DC, carnitine C7: DC, 2-hydroxybutanoic acid, 3-hydroxybutanoic acid, malonic acid, and methylmalonic acid could be key small molecule compounds in curing and drying processing. These findings are valuable for understanding the mechanisms underlying flavour changes occurring during fish curing and drying processes.