Comparative evaluation of muscle quality, nutritional composition, and flavor in rainbow trout (Oncorhynchus mykiss) cultured between freshwater and seawater.

Rainbow trout is an important fish species that can be cultured in both freshwater and seawater. Nevertheless, its muscle quality has not been systematically evaluated until now. This study was conducted for the comparison of meat quality in rainbow trout cultured between freshwater and seawater. Results showed that seawater significantly improved growth performance and muscle hardness, gumminess, and chewiness. It also promoted the accumulation of Na+, Cl-, Ca2+, and sweet-tasting amino acids. In addition, seawater-cultured rainbow trout had higher contents of unsaturated fatty acids and inosine monophosphate, indicating better nutritional quality. Electronic tongue analysis revealed clear differences in flavor characteristics between two environments. Volatile compound analysis showed that seawater-reared individuals contained higher levels of esters, aldehydes, and hydrocarbons, which are associated with sweet, pleasant, and roasted aromas. Overall, seawater aquaculture can effectively improve the meat quality and flavor of rainbow trout, providing support for the development of seawater farming.