Effects of Feeding Ice Fish and Feed on the Flavor of Chinese Crab

Abstract— Eriocheir sinensis is an important aquaculture animal in China. In order to compare the effects of feeding chilled fish and feed on the flavor of Chinese mitten crab, this experiment compared the volatile flavor substances, sensory evaluation and the differences of amino acids (AA), fatty acids (FA) and nucleotides. As a result, the sweet taste, fresh taste and grass flavor of Chinese chelate crab in the feed group were significantly higher than those in the ice fish group (P<0.05). The fishy smell of the feed group was significantly lower than that of the ice fish group (P<0.05). Amino acids in feed group and chilled fish group were not significantly different. Only 5'-adenosyl monophosphate (AMP) was found to be significantly different between the two groups (P<0.05), and the AMP content in feed group was significantly higher than that in ice fish group. The fatty acid composition of feed group and chilled fish group varied greatly. compared with the chilled fish group, saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) in feed group decreased significantly (P<0.05), while high unsaturated fatty acids (PUFAs) increased significantly (P<0.05). Gas chromatography-mass spectrometry (GC-MS) was used to study volatile small molecules in muscle difference, compared with the ice fish group, the content of aldehydes in the feed group increased significantly (P<0.05), and the content of ketones and nitrogen compounds decreased significantly (P<0.05). The enzyme (lipoxygenase) that catalyzes the formation of aldehydes from polyunsaturated fatty acids was further analyzed. Compared with the ice fish group, the expression of LOX 5 genes and proteins and LOX enzyme activity in the feed group were significantly increased (P<0.05).