Abstract:To investigate variations in cold-water fish muscle quality under different growing environments and their causes, this study focused on masu salmon (Oncorhynchus masou) as a target object. Samples were collected from migratory and landlocked triple, breeding and non-breeding group masu salmons. The appearance, texture, nutritional composition, and omics features of the back muscles of masu salmon were compared. Results showed that the fracture, gumminess, and water- holding capacities of the masu salmon triple group were significantly higher than those of the migratory, breeding, and non-breeding groups (P<0.05). The adhesive force, shear force, and cohesiveness of the triple group were significantly lower than those of the migratory, breeding, and non-breeding groups (P<0.05). The pH of the triple-breeding group was significantly lower than those of the breeding and non-breeding groups (P<0.05). The hardness of the migratory group was significantly higher than that of the non-breeding group (P<0.05). The redness of the triple-breeding group was significantly higher than those of the migratory, breeding, and non-breeding groups (P<0.05). The crude fat and water content of the masu salmon triple group were significantly higher than those of the migratory, breeding, and non-breeding groups (P<0.05). The crude protein and ash content of the migratory group were significantly higher than those of the landlocked triple, breeding, and non-breeding groups (P<0.05). The TAA, EAA, and DAA contents of the migratory masu salmon were significantly higher than those of the landlocked masu salmon (P<0.05) and showed significant differences between the groups (P<0.05). The contents of saturated fatty acids (∑SFA), monounsaturated fatty acids (∑MUFA), and polyunsaturated fatty acids (∑PUFA) of the landlocked masu salmon were significantly higher than the migratory masu salmon (P<0.05), and the triploid group was highest. The eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) contents of the triploid group were significantly higher than those of the migratory, breeding, and non-breeding groups (P<0.05). The fiber diameter of landlocked masu salmon was significantly larger than that of migratory masu salmon (P<0.05). The results showed that the protein and amino acid contents of landlocked masu salmon were slightly lower than those of migratory masu salmon. However, landlocked triploids were better than migratory and other breeding groups in terms of muscle texture, color, fatty acid composition, and muscle fiber structure. These results provide a scientific basis for variety breeding optimization, differentiated breeding, and functional feed development in cold-water fish.