From the moment the crab dies, the germs in the crab will multiply rapidly. If you use it for food, you don't need to keep it. Even if it is just dead, don't try it. You should throw it away decisively. Freezing is useless, because the temperature of the refrigerator can't limit the breeding and reproduction of germs at all. Maybe other things in the refrigerator will be contaminated by germs.

Crabs are different from fish. Even if the fish is dead, it can still be eaten under normal circumstances as long as the meat quality has not deteriorated, but crabs are completely different.

The metabolism of live crabs can compete with microorganisms and inhibit their reproduction; After the death of crabs, microorganisms will multiply rapidly with rich nutrients, and crabs will rot and deteriorate to produce a variety of toxins. People may cause fever, vomiting, abdominal pain, diarrhea and other food poisoning symptoms after eating.

Extended data:

Tie up the crabs, put them in the cold room, preferably on the fruit layer, spread wet towels on the crabs, don't twist them too dry, and don't fold the towels, so that they can be preserved for a period of time.

Keep crabs in water. If 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.

Keep it moist, it's not a problem to live for a week or two, just don't soak it in water. Farming places are usually placed in cement pools, which are sprayed with water every day, sometimes for a month or two.