Exploring the lipid oxidation mechanisms of Antarctic krill oil (Euphausia superba) during storage based on relationship between lipidomics and volatilomics

Antarctic krill oil (AKO) is known for its richness in unsaturated fatty acids, but its oxidative sensitivity hinders its utilization in functional foods. In this study, qualitative and quantitative analyses of lipids in AKO based on lipidomics were performed, and gas chromatography-ion mobility spectrometry was used for monitoring AKO flavor changes during storage. 1678 lipids were identified, belonging to 26 subclasses of AKO, with glycerophospholipids being the most abundant. Through a chemometrics analysis, 326 differentially abundant lipids and 30 characteristic volatile flavor substances with VIP > 1 and P < 0.05 were screened in AKO. 10 lipid molecules were considered as key precursor lipids for the oxidation of AKO, namely LPA 20:2, PA 16:1_20:5, PI-Cer 13:2;2O/16:2;O, PMeOH 12:0_22:6, CAR 20:1, DG 22:1_18:3, DGCC 8:0_17:0, LPA 17:0, MG 18:1, and TG 16:1_17:2_36:10, which were correlated with key aromatic compounds. This study provides a theoretical basis for understanding the oxidation mechanism during AKO storage.