Morphological structure and quality characteristics ofcultured Larimichthys crocea in Ningde

Ningde area is the main producing area of Larimichthys crocea in China. It is a useful reference for revealing the morphology, digestive structure and quality characteristics of cultured L. crocea in Ningde, and for the deep processing and sustainable breeding of L. crocea. In this paper, the biological parameters and food physicochemical analysis, the shape parameters of L. crocea, the proportion of each part and the rate of meat yield, the organ parameters of the digestive tract, the diameter of myofibrils, texture, color, cooking loss rate, water loss rate, pH, amino acid composition and taste, fatty acid composition, etc. were measured and analyzed. The results showed that the condition factor of L. crocea in Ningde area was 2.25%, the fish fillets accounted for 57.32% of the body weight, and the meat yield was high; the fish head, skeleton and fish tail accounted for 27.35% of the body weight. In the digestive system, the fish stomach is more developed, there are 15 ring pyloric caeca, and the length of the fish intestine is moderate, which reflects the digestive characteristics of the feed of cultured L. crocea. Its internal organs accounted for 10.73% of body weight, while the liver accounted for 36.65% of the visceral weight. The fish maw was thicker, accounting for 15.74% of the visceral weight. The liver and fish maw were worthy of deep processing. The cultured L. crocea has white muscle color, pH 6.66−6.74, muscle fiber diameter of 104.21μm. The muscle fiber density is 153.13 per square millimeter. The fish meat is tender. Its amino acid type is complete, and essential amino acids account for 41.93% of the total amino acids, and the content of lysine is higher, the umami amino acid accounts for 45.92% of the total amino acid, and the fish meat is fresh and sweet. The fatty acids in muscle are mainly unsaturated fatty acids, accounting for 62.04% of the total fatty acids, of which essential fatty acids account for 28.45% and EPA and DHA account for 20.01% of the total content. It is a high-quality food supplement for essential fatty acids and high unsaturated fatty acids.