Crabs are afraid of the cold when the water temperature drops. Although crabs are cold-blooded animals, they are not very cold-resistant. When the water temperature drops, their own body temperature will also drop. When the temperature is below 10 degrees Celsius, crab activity will decrease; when it is below 5 degrees Celsius, they will stop all activities and enter a state of hibernation; when the temperature is below minus 1 degrees Celsius, the cells in their bodies will rupture and freeze to death. Crabs cannot tolerate cold weather and lower water temperatures, so in winter they must be warmed to survive. Research shows that crabs’ favorite water temperature is 22-25°C. In winter, the water temperature must be kept above 20°C so that they can survive the winter safely.

Can frozen crabs be eaten?

Whether frozen crabs can be eaten depends on the situation. Crabs that are frozen to death in the frozen layer are generally edible, because the temperature of the frozen layer is basically minus ten degrees Celsius. Crabs generally do not produce bacteria and harmful substances, but be careful not to thaw midway. However, crabs that have died naturally cannot be eaten, because crabs will produce substances harmful to the human body after death. The histoxic acid in the crab's body will decompose to produce histamine, and histamine is a toxic substance that increases with the time of death. , the crab body will accumulate more and more histamine. Moreover, after the death of crabs, a large number of pathogenic microorganisms such as parasites and bacteria will be produced. Eating such dead crabs will cause intestinal bacterial infection and cause food poisoning. In severe cases, it may cause nausea, vomiting, abdominal pain, diarrhea and other conditions.