The color of the body surface of shrimp and crab is mainly determined by the pigment cells in the dermis of its crustaceans. Usually there are many pigments on the shell surface of shrimp and crab. These pigments are basically blue-black, and one of them is astaxanthin, which is usually combined with protein, so it will not appear red.
When crabs and shrimps are heated at high temperature, many pigments will be destroyed one by one, because astaxanthin is more stable and difficult to be destroyed at high temperature, so astaxanthin can be separated from protein at this time, thus showing its original red color, which is magically highlighted at this time, so the shrimps and crabs seen at this time are mainly red.
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Nutritional analysis
1. Shrimp is nutritious, soft and easy to digest. It is excellent food for people who are weak and need to be nursed back to health after illness.
2. Shrimp is rich in magnesium, which plays an important role in regulating heart activity and protecting cardiovascular system. It can reduce the cholesterol content in blood, prevent arteriosclerosis, dilate coronary artery, and help prevent hypertension and myocardial infarction.
3. Shrimp has a strong breast enhancement effect and is rich in phosphorus and calcium, especially suitable for children and pregnant women.
4. Scientists at Osaka University in Japan found that astaxanthin in shrimp helps to eliminate the "jet lag" caused by jet lag.
5. No matter what kind of shrimp, it is rich in protein and has high nutritional value. Its meat is as soft and digestible as fish, without fishy smell and bone spurs. At the same time, it is rich in minerals (such as calcium, phosphorus, iron and so on. ) Shrimp is also rich in iodine, which is very beneficial to human health. According to scientific analysis, protein accounts for about 16 ~ 20% of the edible part of shrimp.
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