The so-called yellow of a crab refers to the eggs of a female crab, and the crab paste refers to the sperm nest of a male crab.

In the fall, the climate gradually changes from cool to cold, and the crabs gradually grow stronger. The digestive glands and ovaries of female crabs grow into crab roe in preparation for winter and reproduction in the coming year (crab roe becomes crab roe in the spring).

At this point, when you peel off the crab shells, you can see a lot of yellow, sticky stuff among the shells and lumps of crab, which is the raw crab roe. When cooked, the yolk turns red, and the darker the red, the stronger the crab.

Male crabs, in preparation for winter, also gradually accumulate fat and grow into crab paste (commonly known as crab oil). When you peel off the shell of a male crab, what you see in the same place is white, sticky stuff, which is crab paste (crab oil). When cooked, the crab paste becomes translucent. The more crab paste there is, the stronger the male crab is.

Crab roe and crab paste are not only delicious, but also nutritious, which is the essence of crabs.

A small number of crabs grow and reproduce exclusively in freshwater, mostly under rocks in mountain streams. There are also a few crabs, such as the ground crab, that can adapt to life on land, burrowing in moist mud holes and migrating to the sea during the breeding season. Most crabs are omnivorous. Some crabs are carnivorous, such as the pike crab, which preys on fish, shrimp and mollusks. A few crabs, such as the stranded window crab, scrape or filter feed on algae and organic debris.

Common seawater crabs are pike crabs, snow crabs, green crabs, etc. Among them, snow crabs are basically dead from the water after capture, and pike crabs can be cultured artificially. Pike crabs, snow crabs intake of food quality and growth environment is better, after death can be eaten, selection should be selected fresh: back shell is greenish-black, with glossy, umbilical cord full, belly white freshness is higher.

The green crab lives in shallow coastal waters and estuarine mud and sandy bottoms, carnivorous, and sometimes feeds on decaying small animals. Once dead, green crab gastrointestinal tract may have toxins and spread to the muscle, so dead green crab should not be eaten. It is best to put green crabs in clean, lightly salted water for temporary purification after purchase to help clean the crab's digestive organs.