Lipidomics Profile, Fatty Acid Distribution and Differential Analysis of Lipids in Dried Shrimp (Litopenaeus vannamei)

This study aimed to identify the lipid composition and the positional distribution of fatty acids in dried shrimp and to select differential lipids and investigate lipid changes and the lipid transformation mechanism during storage using lipidomics analysis. Results showed that a total of 790 lipids belonging to 7 major classes were identified, among which glycerophospholipids were the most abundant, followed by glycerolipids and sphingolipids. In phosphatidylcholine (PC), phosphatidylethanolamine (PE), triglycerides (TG), and diglycerides (DG), saturated fatty acids were found to be mainly located at the sn-1 position, while unsaturated fatty acids, especially oleic acid, linoleic acid, docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA), were mainly distributed at the sn-2 position. Using multivariate statistical analysis, 151 differential lipids were selected, 121 of which were up-regulated and the remaining 30 were down-regulated, indicating that storage had a significant effect on the types and contents of lipids in dried shrimp. After storage for 20 days, the relative contents of lyso-phosphatidylcholine, lyso-phosphatidylethanolamine, and lyso-phosphatidylserine in dried shrimp increased, and the relative contents of PC, PE, and phosphatidylserine decreased significantly, indicating the occurrence of lipid transformation.