There is no particularly scientific statement on how long after death crabs cannot be eaten, but it is best to steam live crabs or freshly dead crabs to eat. Because crabs will produce a toxic substance called "histamine" in their bodies after death. Crabs that have been dead longer will produce more toxic substances, which will be extremely harmful to the human body after being eaten.

1. Can you eat dead crabs? Will it be poisonous if eaten?

You cannot eat crabs after they die. The meat quality of the crabs after death will change, which will harm people's health. The reasons are analyzed as follows:

Crabs in the water mainly feed on dead fish, dead shrimps and other dead animal carcasses, so a large number of bacteria will be present in the crab's body. Live crabs can eliminate bacteria from the body through their own metabolism. , but dead crab bacteria will accumulate in the crab body and produce toxins. People who eat dead crabs will be poisoned.

2. How long does it take to eat a crab after it is dead?

Even though it is a freshly dead crab, the protein and fat contained in it will become nutrients for bacteria, leading to the growth of a large number of bacteria. At the same time, the protein will be decomposed into cadaverine and histamine. Cadaverine and histamine have Toxic, eating it will cause poisoning, and histamine can cause allergies, numbness of the limbs, skin allergies, general weakness, and even allergies such as asthma and difficulty breathing.

If you find a dead crab, you will not be poisoned if you cook it and eat it immediately. But for the sake of your health, it is best not to eat dead crabs.

3. What will happen if you eat a dead crab?

1. Poisoning

Crabs are scavengers and often eat dead animal carcasses. Because crabs contain some bacteria, pathogenic bacteria and other substances outside their bodies, crabs are poisonous when they are about to die. When the crab dies or dies, bacteria will quickly decompose the protein of the hairy crab, causing the content of cadaverine and histamine to rise rapidly. They are toxic substances, so eating them can cause poisoning or allergies.

2. Diarrhea

After the crab dies, the bacteria in the body quickly invade the inside of the hairy crab. Hairy crabs are rich in protein and fat, and rich in nutrients. The invading bacteria breed quickly and are easy to eat. Diarrhea, vomiting, abdominal pain, etc. occur.

4. How to tell whether a crab is alive or dead?

1. Pick up the bundled hairy crab and touch its eyes with your hands to see if it blinks. Blinking means it is alive.

2. Take half a basin of water and put the tied crab into the water. Check whether the crab's mouth spits bubbles. Bubbles indicate freshness. (Remember, do not put the tied crabs into the water for a long time, because there is insufficient oxygen in the water, and the crabs will soon suffocate to death)

3. Touch the crab claws, straighten the smallest claws, and see Does it bend naturally quickly? If it bends naturally, it means it is fresh.

4. Untie the tied crab and see if the crab can crawl. If it can crawl, it means the crab is very vigorous.

5. How to choose crabs?

1. Look at the crab shell

If the back of the shell is black and green with light, it means the meat is thick and strong; if the back of the shell is yellow, the meat is thinner.

2. Look at the belly button

If the belly button is protruding, it is full of fat; while if the belly button is recessed, there is insufficient fat.

3. Look at the chelicerae

If the chelicerae is covered with villi, it means the foot is old and healthy; if there is no villi on the chelicerae, the body is soft and without fat.

4. Look at the vitality

Place the river crab on its back with its belly facing the sky. Those that can turn over and crawl quickly will appear old and healthy; those that cannot turn over and crawl will have poor vitality and cannot be bought.

5. Look at the male and female crabs

Around the ninth month of the lunar calendar, the gonads of female crabs are mature and the meat is plump; after the tenth month of the lunar calendar, the gonads of male crabs are mature and the meat is plump.

Dead crabs cannot be purchased and eaten no matter how cheap they are. In addition, crabs contain more histidine in their bodies. The longer the crab dies, the more histamine accumulates in its body. Histamine is a toxic substance that can cause poisoning when it accumulates in the body to a certain extent.