Abstract: In order to comprehensively and objectively evaluate the nutritional value of shark meat and fin (including whole fin and fin cartilage), the nutritional composition of shark meat and fin from Carcharhinus falciformis and Prionace glauca was analyzed. The results showed that protein content was high in both shark meat and fin (24.34%–37.03%), and was higher in shark fin than in shark meat for the same species. Crude fat content was very low in shark meat and fin from each species, less than 0.50%. Ash content was surprisingly high (6.18%–7.09%) in whole fin due to its sandy surface, but it was just slightly higher in meat than in fin cartilage (1.23%–1.63% vs. 0.86%–0.90%). Both shark meat and fin contained a wide variety of amino acids and the latter had a higher level of total amino acids (TAA) than the former. Nevertheless, the content of essential amino acids (EAA) was higher in shark meat than in fin (41.94%–42.42% vs. 17.93%–22.61%), and only shark meat met the Food and Agriculture Organization/World Health Organization standard for amino acid profile (EAA/TAA ≥ 40% and EAA/non-essential amino acids (NEAA) ratio ≥ 60%). Therefore, the nutritional value of amino acids in shark meat was higher than shark fin, and shark meat but not fin was a source of high-quality protein. The amino acid score (AAS), chemical sore (CS) and essential amino acid index (EAAI) results showed that the AAS score, CS score and EAAI score of shark meat were approximately twice higher than those of shark fin, indicating that the nutritional value of amino acids in shark meat was significantly higher than that of shark fin. According to AAS and CS evaluation, methionine and cysteine were the first limiting amino acids in shark meat, while leucine (according to AAS score) or methionine + cysteine (according to CS score) was the first limiting amino acid in shark fin. Thirteen fatty acids were detected in shark meat and the contents of saturated fatty acids (SFA), polyunsaturated fatty acids (PUFA) and monounsaturated fatty acids (MUFA) decreased in that order. Similarly, 16 fatty acids were detected in shark fin, and the content of various fatty acids followed the decreasing order of SFA > MUFA > PUFA. Both shark meat and fin were rich in oleic acid, docosahexaenoic acid (DHA) and arachidonic acid (ARA), which are unsaturated fatty acids with important physiological activities and met the ideal fatty acid profile (PUFA/SFA ratio > 0.4), but the PUFA/SFA ratio of shark meat was significantly higher than that of shark fin. Both shark meat and fin were rich in collagen, and its level was significantly higher in the latter than in the former (7.61%–11.99% vs. 0.27%–0.41%). Chondroitin sulfate was also found in both shark muscle and fin, and its content was very high in whole fin (2.67 mg/g and 10.87 mg/g for Carcharhinus falciformis and Prionace glauca, respectively), but low in muscle and fin cartilage (< 1.2%).

Key words: shark meat, shark fin, whole fin, fin cartilage, nutritional value