Comparative evaluation of nutritional value and flavor quality of muscle in triploid and diploid common carp: Application of genetic improvement in fish quality

Abstract

Hybridization can combine the advantages of different strains to produce new varieties, which may also improve the quality of fish. Triploid common carp (3n = 150) were derived from the female diploid common carp (Cyprinus carpio L.) (2n = 100) crossing with the male allotetraploid (4n = 200). Nutritional value and flavor quality were investigated in triploid and diploid common carps fed with the same diet for 13 weeks. Results indicated that the triploid common carp exhibited significantly higher levels of crude protein, essential and total amino acids, eicosapentaenoic acid (EPA, 20:5 n-3), docosahexaenoic acid (DHA, 22:6 n-3), total polyunsaturated fatty acids (PUFAs) and the ratio of n-3 to n-6 PUFAs in muscle than the diploid common carps (P < 0.05). Additionally, the concentration of sour and bitter amino acid in the muscle of triploid common carp significantly decreased than that in diploid (P < 0.05). Triploid common carp had significantly higher concentration of salt amino acid (P < 0.05) and kept unchanged the content of sweet and umami amino acid than diploid (P > 0.05). Furthermore, the characteristic volatile compounds which including styrene, ethylbenzene, butylated hydroxytoluene, 1-octen-3-ol and (Z)-β-ocimene were screened in the muscle of diploid and triploid common carps, of which styrene and 1-octen-3-ol were the odor-active compounds. Triploid common carp had significantly higher concentration of styrene and 1-octen-3-ol than diploid (P < 0.05), of which 1-octen-3-ol was the highest odor-active compound in triploid. These findings demonstrated that the triploid common carp had improved nutritional and flavor quality, which provided a novel insight for the application of hybridization in fish quality improvement.