MUSCLE NUTRITIONAL COMPARATIVE OF FOUR DIFFERENT GEOGRAPHICAL SILURUS ASOTUS GROUPS

To investigate muscle nutritional components of Silurus asotus in the Yellow River, the Songhua River and the Bigyang River, standard method was used to determine nutritional composition in back muscles of the four natural Silurus asotus groups. Silurus asotus samples were collected from Baiyin group in Yellow River (BY), Zhengzhou group in Yellow River (ZZ), Donggang group in Bigyang River (DG) and Harbin group in Songhua River (HEB). The results showed that crude protein of BY was significantly (P0.05) higher than that of ZZ and DG, and crude lipid of BY was significantly (P0.05) higher than that of ZZ, DG and HEB. Unsaturated fatty acids are the major fatty acids in muscle, and the highest content of monounsaturated fatty was oleic acid. Oleic acid content of BY was significantly (P0.05) higher than that of ZZ, DG and HEB. EPA + DHA contents of BY were significant lower than those in other 3 groups (P0.05). Glutamic was the most abundant amino acid. Values of other amino acids except valine and isoleucine by amino acid score (AAS) were close to or higher than 1. The evaluation of amino acids by chemistry score (CS) was higher than 0.5. Valine and Isoleucine were the first and second limiting amino acids, respectively. HEB showed the highest score in essential amino acid index (EAAI), and DG had the lowest in EAAI. In conclusion, difference nutritional values were observed between BY and other three groups (ZZ, DG and HEB) that illustrated similar nutritional value, which might be explained by various geographical environments.