COMPARISON OF MUSCLE COMPOSITIONS BETWEEN RED-FLESHED AND WHITE-FLESHED CHINOOK SALMON (ONCORHYNCHUS-TSHAWYTSCHA)

Sexually mature chinook salmon were classified as red- and white-fleshed, based on the carotenoid levels of muscle and integument. Chinook salmon with high levels of total carotenoids in either muscle or integument were regarded as red-fleshed, regardless of their muscle color. The salmon with low carotenoid levels of muscle and integument were considered white-fleshed. There were no significant differences in muscle compositions of moisture, protein, and lipid. The changes in "a" value, which expresses the red color of the muscle, were parallel with those of the carotenoid levels, as indicated by a coefficient of correlation of 0.95, while no close correlation (r=0.09) was found between lipid and carotenoid levels of red- and white-fleshed salmon. These results suggested that changes of muscle composition occurring during spawning migration of chinook salmon are related to their physiological state, but not their muscle color type.