As far back as 200 BC, the Chinese had learned to make soy foods and used soybeans as the main source of quality protein. Although soy protein is the only one that rivals meat, cooked soy does not cause appetite and can cause flatulence. The birth of Chinese tofu changed the fate of soybeans. Since then, tofu has become an indispensable part of popular recipes, and it is also the main ingredient of Chinese vegetarian dishes.
Regarding the inventor of tofu, there has been controversy, but it is generally believed that Tofu was invented by Huainan King Liu An. In 164 BC, Huainan King Liu An was seeking medicine for immortality and mistakenly added gypsum to soybean milk to form a fresh and smooth tofu.
The tofu was introduced to Japan during the Tang Dynasty. It is said that in 757 AD, when Jianzheng came to Japan, in addition to the introduction of Buddhist scriptures, the technology of making tofu was also introduced to Japan. Until the 19th century, tofu was introduced into Europe, Africa, America, and other regions and countries.
In the middle and late 20th century, with the frequent and deepening cultural exchanges between China and foreign countries, with the rise of vegetarianism and healthy eating concepts in Europe and the United States, tofu has become popular in the West, with tea, porcelain, and silk.
Tofu is also known as the “Four Inventions” of Chinese food, together with bean paste, soy milk, and bean sprouts.
For the production of tofu, firstly, the soybeans (also made of beans such as black beans, peanuts, mung beans, white beans, peas, etc.) are shelled, washed, and soaked in water for a suitable period of time. Add a certain percentage of water and grind it into raw soy milk. Next, the raw soy milk is packed in a special cloth bag, the bag mouth is tightly squeezed, and the soy milk juice is squeezed out from the cloth bag. This is called “squeezing the pulp”. After the “slurrying” is finished, the bag opening is opened, the water is poured, and the bag mouth is tightened, and then squeezed again.
After the raw soy milk is squeezed, pour it into the pot and heat to boiling to 90-100 °C. When cooking soy milk, you should cook while frying the foam floating on the surface. After the soy milk is cooked, it is necessary to use a salt halide whose main component is magnesium chloride, or a gypsum “dot halide” whose main component is calcium sulfate. After “dot-halogen”, the soy milk will condense into a tofu flower containing a lot of water.
After about 15 minutes, the tofu flower is kneaded into a covered wooden tray. After the fullness, wrap the tofu flower with a cloth, cover the board, press for 10-20 minutes, and the fresh tofu is finished.
There are about 15 common bean varieties: North tofu, South tofu, Lactone, Stinky tofu, Soybean Milk, Dried tofu, Crisp tofu, Tofu Skin, Tofu Bubble, Gray tofu, Tofu Bamboo, Tofu Flower (Tofu Brain), Oil Tofu Skin, Mao tofu, Fermented bean curd.