Chemical and LC–MS-based lipidomics analyses revealed changes in lipid profiles in hairtail (Trichiurus haumela) muscle during chilled storage

Chemical and liquid chromatography-mass spectrometry (LC-MS)-based lipidomics techniques were used to investigate the alternations of lipid profiles in hairtail (Trichiurus haumela) muscle after chilled storage for six days. The chemical results showed that the peroxide values (PVs) and thiobarbituric acid reactive species (TBARS) content in the muscle increased significantly, from 0.43 meq/kg of lipids and 0.86 mg malondialdehyde (MDA)/kg of muscle to 8.36 meq/kg and 10.69 mg MDA/kg, respectively, after six days of chilled storage. LC-MS-based lipidomics analyses detected 1446 lipids in hairtail muscle tissues assigned to 26 lipid categories, including 257 triglycerides (TGs), 232 phosphatidylcholines (PCs), 149 phosphatidylethanolamines (PEs), and 78 ceramides (Cers), among other classes. In total, 175 and 67 differentially abundant lipids (DALs) accumulating at low and high abundance levels, respectively, were detected in chilled stored hairtail (CSH) compared to fresh (FH) samples. Among the DALs, the PCs, PEs, and TGs/diglycerides (DGs) as predominant lipid components were more prone to oxidation/hydrolysis, likely owing to their highly unsaturated properties. The apparent alterations between the CSH and FH samples might result from lipid lipolysis, modifications of main- and side-chains, backbone cleavage, and/or the decomposition of lipids during chilled storage.