What method was used to order tofu in ancient times? It would be better to be detailed, thanks

1. Material selection: select fresh soybeans, sieve by dry selection method or water selection method to screen out impurities such as sundries, inferior beans, grass and sand.

2. Soaking beans: Soak soybeans in water to remove impurities floating on the water surface, and the amount of water is subject to submerged soybeans. In the process of soaking, to prevent the water quality of the soaked beans from becoming sour and rancid, and affecting the quality of soybean milk, change the water in time according to the specific situation, and the soaking time varies according to the temperature, generally 4-6 hours in summer; Winter can be extended to 9-12 hours.

3. Grinding: Add the soaked beans to the refiner many times, add water while adding soybeans, and grind them into soybean milk paste, generally about kilograms of soaked beans and water.

4. Filtration: Soybean milk filtration is generally done with a filter cloth or flour bag, add about 20 kilograms of warm water to the ground soybean milk paste 5 kg (about 1 kg of dried soybeans), mix evenly and then put it into the cloth bag, hang the cloth bag, shake it by hand, wait for the slurry to flow out, and repeat the operation 3-4 times until the slurry is drained.

5. Boiling pulp: Take the filtered raw soybean milk and put it in the pot, heat and boil (or heat with water steam) until the soybean milk foam on the pot surface bursts, and remove the fire to get cooked soybean milk.

6. Slurry: Slurry is generally used as a coagulant, and 1 kg of dried soybeans needs to be equipped with about 10 grams of salt brine (30 grams of liquid salt brine with 25%-30% concentration is dissolved). Methods of dispensing slurry:

Scoop the boiled soy milk out of the pot and let it cool slightly, and then dispense the pulp when the temperature drops to 80. When the soybean milk sticks to the spoon, the stirring slows down, and the speed of adding salt brine is also slowed down accordingly, until the soybean milk appears corn-sized tofu grains, stop stirring, cover the pot, and keep it for about half an hour to carry out the pulping process.

7. Pulp: Pulp is to pour the tofu brain into a wooden lattice covered with cotton cloth, wrap it, squeeze it with a heavy object, and squeeze out the water.

Processing and production method of salt-brine tofu: add a small amount of salt and brine after soaking, grinding, filtering, and boiling the soybean to make the protein of the tofu condense into "flowers", and then put it into a wooden frame to press off the excess water to form brine tofu. The tofu made by this method is more tender than the tofu made from gypsum and has no roughness.

Salt-marinated tofu can also be made into dried tofu, chili tofu, and fried tofu, which is nutritious and consumed in large quantities.