WANG Shihui, SU Junjie, ZHANG Shuqi, LUO Liang, ZHANG Rui, GUO Kun, ZHAO Zhigang
To investigate the nutritional quality and heavy metal safety risk of Chinese mitten crab (Eriocheir sinensis) and the crayfish (Procambarus clarkia) farmed in cold ponds with the similar environments, the edible yield, proximate composition(moisture, crude protein, total lipid and ash), fatty acids, mineral elements, and heavy metal (Cd,Cr,Hg and Pb) in these two specieswere determined by dissection, biochemical composition analysis, area normalization, and inductively coupled plasma mass spectrometry. The results showed that the average body weight, gonadosomatic index, meat yield, and total edible yield of E. sinensis were significantly higher than those of P.clarkia (P<0.01). The moisture and crude protein contents in the hepatopancreas of E. sinensis were significantly higher than those of P.clarkia, but the crude protein content in the muscle was significantly lower (P<0.01). The total saturated fatty acid, C18:3n3 (α-linolenic acid), C22:6n3 (docosahexaenoic acid), and total 3-ω polyunsaturated fatty acid contents of E. sinensis were significantly lower than those of P.clarkia (P<0.01), whereas the total polyunsaturated fatty acid content was significantly higher (P<0.01). The contents of Na, Ca, Zn, Cu, and total minerals in the hepatopancreas of E. sinensis were higher than those in the P. clarkia, but the contents of Fe and Mn were lower. The contents of Na, Ca, Fe, Zn, Cu, Mn, Se and total minerals in the muscle of E. sinensis were higher than those in the P. clarkia, but K content was lower (P< 0.01). The contents of the heavy metal elements Cd, Cr, Hg, and Pb in the hepatopancreas and muscle of P.clarkia were slightly higher than those in. In summary, had higher body weight, gonadosomatic index, meat yield, total edible yield, and total PUFA, Na, Ca, Zn, Cu, and total mineral element contents compared to P.clarkia, whereas the edible tissues of P.clarkia had higher α-linolenic acid, docosahexaenoic acid, K contents as well as higher crude protein content in muscle. The poisonous heavy metal contents in the edible tissues of both species were lower than the national food safety standard, making them safe sources of aquatic food.
