Analysis of Lipid Molecule Profiling and Conversion Pathway in Mandarin Fish (Siniperca chuatsi) during Fermentation via Untargeted Lipidomics

Lipids are the key aroma contributors and nutrients infermentedfish products. A total of 376 lipid molecules were identified in mandarinfish during fermentation by untargeted lipidomics, including glycerolipids,glycerophospholipids, lysoglycerophospholipid, sphingolipids, fattyacids (FAs), and sterol lipids. Both lipid composition and contentchanged dynamically during fermentation. Triglyceride (TAG, 30.05%)and phosphatidylcholine (PC, 14.87%) were the two major lipids, withespecially 39.36% saturated FAs in PCs and 35.34% polyunsaturatedFAs in TAGs. The content of TAGs and PCs reached a peak point at 0and 6 days, respectively. Fermented mandarin fish expressed a highnutritional value, and the ratio of total linoleic acid/total linolenicacid was about 5:1. Glycerophospholipid metabolism was a potentialmetabolic pathway, and the oxidation of derived FAs contributed toflavor. These data progress in understanding lipid dynamic variationduring fermentation and provide thoughts on controlling the flavorquality and safety of fermented fish products.