Tofu is a traditional soybean food in China. It is a soy protein gel product. The denaturation of soybean protein by heat treatment of raw soybean milk is a necessary condition for the formation of tofu.

Blood tofu, also known as blood tofu, originated from Yunnan ethnic minorities. It is a food made by adding salt to animal blood and directly heating and solidifying. Common blood exuberance is made of duck blood, chicken blood and pig blood.

Protein is denatured by heating. It can be seen that tofu and blood tofu are related to the degeneration of protein.