Key lipid molecules in hepatopancreas of Eriocheir sinensis: Identification and thermal oxidative degradation characteristics.

The hepatopancreas of Eriocheir sinensis are the key parts that form its unique flavor. Lipids are important parts of hepatopancreas; hence, this study used UHPLC-Q E Orbitrap mass spectrometer to investigate the changes in the lipid composition of crabs formed from thermal oxidation system. The results demonstrated that key lipids in the hepatopancreas of female Chinese mitten crabs were phosphatidylethanolamine (PE) and free fatty acid (FFA) during the steaming process. The key fatty acids of PE were C18:1, C18:3, C20:3, C20:4, C20:5, and C22:6. The degradation rate of C24:0 in FFA was greater than the synthesis rate. Principal component analysis, partial least square analysis combined with hierarchical cluster analysis found that PE (16:0/20:5), PE (18:1/20:4), PE (16:0/22:6), PE (16:0/20:4), PE (16:0 /16:1), PE (16:0/18:2), PE (18:0/20:5), PE (18:0/22:6), PE (18:0/20:4), PE (16:0/18:1), PE (18:0/18:2), PE (18:0/22:5), and PE (18:0/18:1) were the key PE molecular species. Simulating thermal oxidation to understand the dynamic change mechanism of lipids is meaningful for processing of Chinese mitten crab products and catering to public sensory orientation. PRACTICAL APPLICATIONS: In this study, the UHPLC-Q E Orbitrap method was used to detect and analyze the molecular species changes of Eriocheir sinensis in the simulated thermal oxidation system, and systematically analyzed the law of changes. Based on these results, we can expand our understanding of the changing characteristics of the hepatopancreas and pancreas of the river crab and provide a direction for the formation mechanism of the aroma substances of E. sinensis during the heat treatment and the improvement of the quality of its products.