The composition of Scylla serrata is rich in protein, and the content of female gonad is as high as 30.98%, which is the highest in fresh protein. Moreover, protein of Scylla serrata has complete amino acids, and the score of essential amino acids is 84.23 ~ 93.58. Protein can promote human growth, maintain nitrogen balance and enhance immune function.

Scylla serrata is rich in fat and unsaturated fatty acids (UFA). The unsaturated fatty acid content of muscle was 74.58%, which was higher than that of Portunus trituberculatus muscle (65.6 1%) and squid head (74.3%). Among them, PUFA is as high as 47.83%, which is nearly 650% higher than Portunus trituberculatus (38.43%). EPA was as high as 18.04%, DHA was 13.52%, Portunus trituberculatus was 15.2 1%, Portunus trituberculatus was 17.69%, and squid head was15.77. Unsaturated fatty acids in liver were the lowest, accounting for 58.32%, which was higher than Portunus trituberculatus. Scylla serrata has a high content of unsaturated fat, especially omega-3 fatty acids EPA and DHA, which cannot be synthesized in human body. EPA can obviously reduce serum triglyceride (TG) and cholesterol (TC), prevent platelet aggregation, delay thrombosis, and prevent cardiovascular and cerebrovascular diseases and prostatic hyperplasia. DHA can promote brain development and enhance brain learning and memory ability.

Scylla serrata is a kind of food with high potassium and low sodium, which is more suitable for patients with hypertension. The content of Ca in its liver is very high, second only to stone snail, shad, shrimp, shrimp skin and clove fish, and the natural organic calcium is easily digested and absorbed by human body. Other essential elements such as magnesium, iron, copper, zinc and manganese in Scylla serrata are also high. The selenium content of all components of Scylla serrata is very high, especially. Participating in the synthesis of coenzyme A and coenzyme Q can protect the structure and function of cell membrane, resist oxidation, scavenge free radicals, antagonize and reduce the toxicity of some poisons, and stimulate the production of immunoglobulin and antibody. Selenium content in human liver, pancreas and kidney is high, while selenium content in serum and hair of cancer patients is low. Therefore, Scylla serrata, especially Formicidae, has nourishing, anti-aging and anti-cancer effects.

The mass ratio of gonad to edible part is 16.52% for females and 1.83% for males. The protein content of female gonad (ointment) is 73.95% higher than that of male, and the EAA/TAA is 9.0 1%, especially the tryptophan content is 3.75 times higher. In terms of fat content, women. Moreover, the black hair is also high 12.52%, but the contents of PUFA, EPA and DHA in male gonads are 40.57% and 90.0% and 86.2% higher than those in female gonads, respectively. In terms of essential inorganic elements, most elements, especially selenium, are high in female gonads, but the cholesterol in female gonads is four times higher than that in male gonads. The content of UFA, especially EPA, in muscle which accounts for about 59.30% of the edible part is quite high, and the content of UFA, especially EPA, in female gonad and liver which accounts for about 16.52% of the edible part is also very high, so eating ointment will not increase triglyceride and cholesterol in human serum. The muscle, female gonad and male of Portunus trituberculatus are raised separately.

To sum up, Scylla serrata is rich in protein, with a complete range of amino acids and a variety of monounsaturated and polyunsaturated fatty acids. The nutrient composition analysis of Scylla serrata is 83, which is rich in inorganic elements, especially selenium and calcium. It is a kind of seafood with high nutritional value and health care function.