1, hairy crabs that have just died or are dead are not edible. This is because when the hairy crab is dying or dead, the oxygen acid in the crab will decompose to produce histamine. Histamine is a toxic substance. With the extension of death time, more and more histamine is accumulated in crabs, and the toxic gas is getting bigger and bigger. Even if crabs are cooked, this toxin is not easy to be destroyed. Excessive ammonia nitrogen must be excreted from the kidneys, so eating dead hairy crabs is very unfavorable to the kidneys. People who eat dead crabs may have symptoms such as vomiting, abdominal pain and diarrhea.

2. Even a half-dead "crab with legs" is not suitable for eating. The infection rate and infection degree of metacercaria of Paragonimus larvae in live crabs are very high. Paragonimus parasitizes in the lungs, which can stimulate or destroy lung tissue, and can cause cough and even hemoptysis. If it invades the brain, it will cause paralysis.

3. According to experts' investigation, the infection rate of paragonimiasis is 20% after eating hairy crabs slightly, 55% when eating pickled crabs and drunken crabs, and 71%when eating raw crabs. The resistance of paragonimiasis metacercariae is very strong, and it usually takes 30 minutes in water at 55℃ or 48 hours in 20% salt water to kill it.

4. Eating raw hairy crabs may cause symptoms such as intestinal inflammation, edema and congestion. Therefore, eating steamed and cooked hairy crabs is the most hygienic and safe. When cooking hairy crabs, it should be noted that it should be cooked for at least 20 minutes after the water is boiled, and the germs of crab meat can be killed only after it is cooked thoroughly. One thing is also very important. When eating, you must remove four substances: crab gill, crab heart, crab stomach and crab intestine, because they contain bacteria, viruses and sludge.

Why can't hairy crabs die easily?

1, Tie up the hairy crabs, put them in the cold room, preferably on the fruit floor, spread wet towels on the hairy crabs, don't twist them too dry, and don't fold the towels. This will keep it for a while.

2. Keep the hairy crabs in water. If the hairy crabs are too thin or want to be stored, you can feed them sesame seeds or broken eggs and add some yellow wine to fatten them up.

3. Keep it moist. It's not a big problem to live for a week or two. Just don't soak it in water. The breeding place is usually placed in a cement pool, sprayed with water every day, sometimes for a month or two.