Compositional characteristics and nutritional quality of Chinese mitten crab (Eriocheir sinensis)

Chinese mitten crab (Eriocheir sinensis) was analyzed for proximate composition, minerals, amino acids and fatty acid composition, and also evaluated for nutritional quality. The yields of crab meat and edible viscera were 24.2% and 9.2%, respectively. The crab meat contained 18.9% crude protein. About 80% of the protein resided in the crab meat portion, while about 90% of the fat was in the viscera. Chinese mitten crab was an excellent source of minerals, particularly zinc, iron, copper and phosphorus. The crab protein contained high amounts of glutamic acid (151 mg/g), aspartic acid (99 mg/g), arginine (99 mg/g), lysine (81 mg/g) and leucine (77 mg/g), and it was a high quality protein with well-balanced essential amino acid compositions. Twenty six fatty acids were found in the crab oil. The monounsaturated fatty acids were predominant with a percentage of 49.8. Oleic acid (18:1) was the dominant fatty acid, followed by palmitoleic acid (16:1), palmitic acid (16:0) and linoleic acid (18:2n − 6); and the percentages were 31.0, 14.3, 14.2 and 11.9, respectively. The ratio of n − 6/n − 3 polyunsaturated fatty acids (PUFAs) was 2.2, and this is a n − 3 PUFA-rich food. In short, the results showed that Chinese mitten crab is a nutritious food.