Divergences of Biochemical Features of Three Reared Trouts; Brook Trout (Salvelinus fontinalis, Mitchill 1814), Rainbow Trout (Oncorhynchus mykiss Walbaum, 1972), and Black Sea Trout (Salmo trutta labrax Pallas 1811)

The objective of this present study is to signify biochemical features of three reared trouts (brook trout, rainbow trout, Black Sea trout) that are economically consequential and reared fish species in the Eastern Black Sea region. The rainbow trout has been reared successfully for a long period of time. However, brook trout and the Black Sea trout have been two new species to be reared in the region with a high potential contribution to the economy. Therefore, there is a strong need to determine and report the differences between the fish (especially the two new species), levels of carbohydrates, energy, carotenes (Vitamin A), fatty acid, and proximate composition (protein, lipid, moisture, and ash). In addition, the lipid indices [Atherogenic Index (AI), Thrombogenic Index (TI), and polyene index (PI)] were also measured and reported for the trouts. Moreover, the color of the fillets of the fish was also measured. The results of this present study show that the average levels of moisture and protein varied while the average levels of lipid and ash were close to each other. The highest levels of carbohydrates, energy, and carotenes were determined in the muscle of brook trout in this study. The highest meat yield was also obtained from brook trout followed by Black Sea trout and rainbow trout. A total of 19 fatty acids were determined for Black Sea trout and brook trout and 17 fatty acids for rainbow trout in the present study. The omega-3 levels of the all trout used for the present study were roughly twice as much as that of the omega-6, except for rainbow trout.