If crabs are frozen directly after death, they are edible. If a crab dies for a while, it can't be eaten. Because after the crab dies, the bacteria in its body will multiply rapidly, which will make the crab deteriorate and stink. If you eat bad crabs, it will cause gastrointestinal diseases and even food poisoning. So when choosing crabs, you must choose fresh ones. If some of them have just died and can't be eaten after returning to China, they can be frozen, but don't freeze them for too long. Try to eat them for a short time.