The head of shrimp contains tyrosinase, which can gradually form quinone under the action of tyrosine, and then form black substances such as true melanin and brown melanin. Therefore, the blackening of shrimp heads is mainly due to the action of enzymes and has little to do with heavy metals. If shrimp happens to eat a lot of dark algae before fishing, the shrimp head may also turn black.

The value of shrimp

Shrimp is rich in magnesium, which plays an important role in regulating heart activity and protecting cardiovascular system. It can also reduce cholesterol content, prevent arteriosclerosis, and help prevent hypertension and myocardial infarction. ?

Shrimp is also rich in astaxanthin, which has a strong ability to scavenge oxygen free radicals. It is an extremely effective antioxidant, which can prevent harmful substances from causing oxidative damage to cells and block the chain reaction of free radicals caused by the degradation of unsaturated fatty acids, thus reducing or preventing the generation of free radicals. It can also effectively protect mitochondria and prevent mitochondria, cell membrane, DNA and amino acids from being destroyed by free radicals.