Improvement of Physiological Metabolism and Flavor Quality of Eriocheir sinensis Ovaries by Dietary Supplementation with Antarctic Krill Meal

Abstract

This study investigated the effects of dietary Antarctic krill meal (AKM) on the physiological metabolism and flavor quality of adult Eriocheir sinensis ovaries during the postharvest temporary rearing. The AKM concentrations tested were 0% (including negative control group and positive control group), 2%, 4%, 6%, and 8%. The results indicate that the E. sinensis ovaries in 8% AKM group produced the highest levels of aroma compounds after thermal processing, including hexanal, heptanal, phenylacetaldehyde, 3-octanone, and 2-methylbutanoic acid ethyl ester. The 8% AKM and negative control group were analyzed by UPLC-MS/MS combined with the nontargeted and widely targeted metabolomics technique. The AKM altered the composition of aroma precursors by adjusting the metabolism of glycerophospholipid, linoleic acid, α-linolenic acid, and amino acid in ovaries. Moreover, lipids composed of polyunsaturated fatty acids (PUFAs) were significantly upregulated (p < 0.05). Dietary supplementation with 8% AKM had the best effect on improving the ovarian flavor quality of E. sinensis. During the postharvest temporary rearing, more aromatic precursors were produced by regulating physiological metabolism. The ovarian flavor was enhanced by lipid oxidation, Maillard reaction, and Strecker degradation during thermal processing.