The origin of tofu can be traced back to the Han Dynasty. During the Han Dynasty, farmers in the Huaihe River valley used stone mills. Farmers soak rice and beans in water, put them in a water mill with a funnel, grind them into paste and spread them in a pot to make pancakes. Pancakes and homemade soybean milk are the daily food of farmers in two stones in Huaihe River. Farmers have accumulated various experiences in planting, boiling, grinding and eating beans. Inspired by the long-term deterioration and coagulation of soybean milk, people finally created the earliest tofu by primitive self-sedimentation.

According to legend, Liu An, king of Huainan in Han Dynasty, began to make tofu. Liu An is the grandson of Emperor Gaozu Liu Bang, and his fief is in Huainan. He once recruited a large number of alchemists, pharmacists and immortals. They know chemical knowledge and improve the method of making tofu by the farmer anonymous. Use gypsum or brine as coagulant to make white and tender tofu. It's possible. Tofu, in the five dynasties, appeared in the north and south food markets. According to the records in Qing Louis at that time, people called tofu "little slaughtered sheep" and thought that the tenderness and nutritional value of tofu could be comparable to that of mutton. In the Song Dynasty, tofu workshops mushroomed all over the country. Those who climb Mount Tai to worship Buddha and visit should try the smooth and delicate Taian tofu. In ancient Tai 'an, there were many bean curd workshops. At night, the grinding wheel of the whole city was rolling and the bean fragrance was overflowing. Anhui Bagongshan bean curd, Hubei Huangzhou bean curd, Fujian Shanghang bean curd, Hebei Zhengding bean curd, Guangxi Guilin yuba, Zhejiang Shaoxing bean curd are all famous bean curd products in ancient times.

Tofu includes South Tofu, North Tofu, Old Tofu, Tender Tofu, Board Tofu, Round Tofu, Water Tofu, Frozen Tofu, Steamed Tofu, etc. They are all fresh products of tofu (including dried tofu, tofu skin, tofu brain, etc.). The fermented products of tofu include stinky tofu, milk rot and long-haired tofu, which are traditional non-staple foods of our people.

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/food/2004-08/25/content _1880291.htm Tofu is rich in nutrition, containing many trace elements necessary for human body, such as iron, calcium, phosphorus and magnesium, as well as sugar, vegetable oil and rich high-quality protein, and is known as "vegetable meat". The digestion and absorption rate of tofu is above 95%. Two small pieces of tofu can meet a person's daily calcium requirement.

Tofu is a nourishing, heat-clearing and health-preserving food. Regular eating can tonify the middle energizer, clear away heat and moisten dryness, promote fluid production and quench thirst, and clean the stomach. It is more suitable for people with heat constitution, bad breath, thirst, indigestion and fever. Modern medicine has proved that tofu not only has the function of increasing nutrition, helping digestion and stimulating appetite, but also is beneficial to the growth and development of teeth and bones, and can increase the iron content in blood in hematopoietic function; Tofu contains no cholesterol, and is a medicinal food for patients with hypertension, hyperlipidemia, hypercholesterolemia, arteriosclerosis and coronary heart disease. Supplementing nutrition for children, patients and the elderly is also a good diet therapy. Tofu is rich in phytoestrogens and has a good effect on the prevention and treatment of osteoporosis. It also has the function of inhibiting breast cancer, prostate cancer and hematological tumor diseases. Sterol and stigmasterol in tofu are both effective components in inhibiting cancer.

Tofu is one of the auxiliary materials in traditional Chinese medicine processing. Boiled tofu is one of the processing methods of traditional Chinese medicine. Implant the medicine into tofu, cover with tofu, and cook over high fire until the tofu is honeycomb-shaped and the color of the medicine becomes lighter, about 4 hours. Such as sulfur, which contains toxic components, can reduce toxicity after being cooked with tofu and be cleaned. Because tofu is rich in protein, it is an amphoteric compound, which can not only precipitate with alkaline substances, but also dissolve some acidic toxic substances to reduce toxic components, and because of its large surface area and many gaps, its adsorption effect is good.

Tofu can also be used for dietotherapy and has certain medicinal value. For example, stewed onion with tofu can cure the first cold and eat it 3 ~ 5 times a day; Cooking crucian carp with tofu can cure measles patients with residual heat and can also be used for lactation; Fried tofu with onion can be used for edema and swelling; Tofu and radish soup can be used to relieve asthma by phlegm fire; Boiled tofu with brown sugar can be used for vomiting blood. I guess you can say that.