Analysis and evaluation of nutritional composition of <i>Schizothorax wangchiachii</i> with three different sizes

This work aimed to comprehensively study the muscle nutritional components of Schizothorax wangchiachii with different specifications. Three sizes (227g, 480g, 1050g) of S. wangchiachii cultured at Jinping-Guandi fish breeding and releasing station in Yalong River were selected as the experimental objects. The composition of conventional nutrients, amino acids, fatty acids, and mineral elements in their muscle was determined, and amino acid nutrition was evaluated. The results showed average meat, meat water, crude fiber, and crude protein contents in the three sizes of S. wangchiachii muscle were 76.36 %, 76.21 %, 0.10 %, and 19.32 %, and there were no differences among them. Average crude fat and ash contents were 2.01% and 2.00%, and the contents were medium size &gt; small size &gt; large size. 18 amino acids (145.95 mg/g) and 8 essential amino acids (EAA) (58.16 mg/g) were detected in muscle, the contents of them were large size &gt; small size &gt; medium size. Six kinds of flavor amino acids (DAA) were determined, and their average was 71.86 mg/g, but the content of large size was significantly higher than that of the small and medium size. A total of 30 fatty acids were detected in the muscle of S. wangchiachii across the three sizes, comprising 11 saturated, 19 unsaturated, 9 monounsaturated, and 10 polyunsaturated fatty acids. The contents of both unsaturated and polyunsaturated fatty acids followed the order of small size &gt; medium size &gt; large size, with the average n-3 polyunsaturated fatty acid content reaching as high as 9.95 %. 9 mineral elements were detected, including 3 macro-elements and 6 micro-elements. The average content of zinc was as high as 9.04 mg/kg, but the average content of selenium was only 0.14 mg/kg. Compared with other common freshwater fishes, the contents of meat, crude protein, flavor amino acids, and unsaturated fatty acids in S. wangchiachii muscle were rich, and the contents of amino acids, fatty acids and minerals were high and reasonable. In summary, S. wangchiachii muscle was a kind of high-quality protein source, had good nutritional value and strong edible taste.