The Wonderful Tofu, Good for Our Health (豆腐)

Tofu or bean curd is a food made by coagulating soy milk and then pressing the resulting curds into soft white blocks. It is of Chinese origin, and it is also a part of East Asian and Southeast Asian cuisine such as Chinese, Japanese, Korean, Indonesian, Vietnamese, and others. There are many different varieties of tofu, including fresh tofu and tofu that has been processed in some way. Tofu has very little flavor or smell on its own, so it can be used either in savory or sweet dishes, and it is often seasoned or marinated to suit the dish.
Tofu is thought to have originated in ancient China, but its precise origins are debated. Tofu and its production technique were introduced into Korea and then Japan during the Nara period. It also spread into other parts of East Asia. This spread likely coincided with the spread of Buddhism because it is an important source of protein in the vegetarian diet of East Asian Buddhists. Li Shizhen in Ming Dynasty described a method of making tofu in Bencao Gangmu.
Tofu contains a low amount of calories, relatively large amount of iron, and little fat. Depending on the coagulant used in manufacturing, the tofu may also be high in calcium and/or magnesium.
Tofu is made by coagulating soy milk and pressing the resulting curds. Although premade soy milk may be used, most tofu producers begin by making their own soy milk, which is produced by soaking, grinding, boiling and straining dried (or, less commonly, fresh) soybeans.
Coagulation of the protein and oil (emulsion) suspended in the boiled soy milk is the most important step in the production of tofu. This process is accomplished with the aid of coagulants. Two types of coagulants (salts and acids) are used commercially.
The third type of coagulant, enzymes, is not yet used commercially but shows potential for producing both firm and "silken" tofu.