Storage evolution in non-volatile and volatile lipid oxidation products of salted large yellow croaker based on targeted lipidomics and GC–MS analysis

Abstract

The hydroxylation and epoxidation of lipids rich in polyunsaturated fatty acids (PUFAs) are significant processes that cannot be overlooked. In this study, the concentrations of non-volatile and volatile compounds derived from lipid oxidation significantly increased during storage of salted large yellow croaker. In which epoxy-fatty acids demonstrated greater stability and steadily accumulated throughout the entire process. The precursors for non-volatile lipid oxidation secondary products included linoleic acid, α-linolenic acid, arachidonic acid, eicosapentaenoic acid, and docosahexaenoic acid. Additionally, compounds such as 1-penten-3-one, decanal, etc., which belong to alcohol, aldehyde, hydrocarbon, ester, and ketone, were identified as key variables. Correlation analysis revealed that non-volatile compounds exhibited a positive correlation with esters and linear alcohols, while showing a negative correlation with aldehydes, ketones, and linear alcohols. These findings have profound implications for a deeper understanding of the complex oxidation processes involved in the storage of salted marine fish with high levels of PUFAs.