First, look at the appearance.
Bad shrimp's head and body, shell and meat are loosely connected. When it is lightly touched by hand, the head and tail are easy to fall off or separate, and its original curvature cannot be maintained.
Second, look at breathing.
If the shrimp dies, there will be no small bubbles in the water from time to time.
Third, look at the color.
Fresh shrimps have shiny shells, river shrimps are blue-green, and prawns are blue-white (female shrimp) or egg-yellow (male shrimp).
Stale shrimp, the shell is black, and the primary color of shrimp turns red or grayish purple.
Fourth, touch the shell
Fresh shrimp, the meat is firm and tender, and it feels hard and elastic by hand.
Stale shrimp meat is soft and has poor elasticity.
Five, smell the smell
The smell of fresh shrimp is normal and there is no peculiar smell.
Deteriorated shrimp will give off an unpleasant smell.
Extended data:
Nutritional analysis
① Shrimp is nutritious, soft and easy to digest, and it is an 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 cholesterol content in blood, prevent arteriosclerosis, dilate coronary artery, and help prevent hypertension and myocardial infarction.
(3) Shrimp has a strong galactagogue effect and is rich in phosphorus and calcium, which is especially suitable for children and pregnant women.
Scientists at Osaka University in Japan have 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. ), and sea 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.
taboo
Shrimp and pumpkin: eating together will cause dysentery, and you can detoxify with black beans and licorice.
Shrimp and juice: Eating together can lead to diarrhea.
Shrimp skin and soybeans: eating together can cause indigestion.
Shrimp skin and red dates: the same food will be poisoned.
References:
Shrimp (crustacean arthropod) _ Baidu Encyclopedia