1 The black paste in hairy crabs is crab paste, but it is black and can be eaten. Crab paste is a collection of semen and organs of male crab seminal vesicle, and it is also a sign of strength and maturity of male crab. The natural state of crab paste is a blue-white translucent colloidal liquid. 2. After steaming, it is translucent, sticky and a little greasy. There are two kinds of crab paste: crab paste and crab paste. Crab paste is slightly sweet and fishy. It contains water, protein, fatty acids, vitamins and other ingredients. 3. Dead crabs are unfit to eat. After death, the rigidity period and autolysis period of Eriocheir sinensis are greatly shortened, and the bacteria in the crab will multiply rapidly and spread into the crab meat. The shell of fresh crab is bluish-black, shiny, with full navel and Bai Jie abdomen. But the shell of the dying crab is yellow, and the crab's feet are soft, so it is difficult to turn it right.