There are many ways to make tofu, and the texture of the final product varies depending upon the method used.
From Wikipedia:“Tofu, also known as bean curd, is a food cultivated by coagulating soy milk and then pressing the resulting curds into soft white blocks.
It is a component in East Asian, Southeast Asian and West African cuisines. Tofu can be soft, firm, or extra firm. Tofu has a subtle flavor and can be used in savory and sweet dishes. It is often seasoned or marinated to suit the dish ...
Tofu has a low calorie count and relatively large amounts of protein. It is high in iron, and depending on the coagulants used in manufacturing (e.g. calcium chloride, calcium sulfate, magnesium sulfate), it can have a high calcium or magnesium content. ...”
Nutrition and health:
“Tofu has a low calorie count and relatively large amounts of protein. It is high in iron, and depending on the coagulants used in manufacturing (e.g. calcium chloride, calcium sulfate, magnesium sulfate), it can have a high calcium or magnesium content.”
Protein: “Tofu is relatively high in protein, about 10.7% for firm tofu and 5.3% for soft "silken" tofu, with about 5% and 2% fat, respectively as a percentage of weight.
In 1995, a report from the University of Kentucky, financed by Solae, concluded that soy protein is correlated with significant decreases in serum cholesterol, Low Density Lipoprotein LDL (″bad cholesterol″) and triglyceride concentrations. However, High Density Lipoprotein HDL (″good cholesterol″) did not increase. Soy phytoestrogens (isoflavones: genistein and daidzein) absorbed onto the soy protein were suggested as the agent reducing serum cholesterol levels. On the basis of this research, PTI, in 1998, filed a petition with Food and Drug Administration for a health claim that soy protein may reduce cholesterol and the risk of heart disease.
The FDA granted this health claim for soy: "25 grams of soy protein a day, as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease." For reference, 100 grams of firm tofu coagulated with calcium sulfate contains 8.19 grams of soy protein. In January 2006, an American Heart Association review (in the journal Circulation) of a decade-long study of soy protein benefits showed only a minimal decrease in cholesterol levels, but it compared favorably against animal protein sources.”
“Tofu has very little flavor or smell of its own. Consequently, tofu can be prepared either in savory or sweet dishes, acting as a bland background for presenting the flavors of the other ingredients used. As a method of flavoring it is often marinated in soy sauce, chilis, sesame oil, etc.”
Varieties: “A wide variety of tofu is available in both Western and Eastern markets. Despite the range of options, tofu products can be split into two main categories: 'fresh tofu', which is produced directly from soy milk, and 'processed tofu', which is produced from fresh tofu. Tofu production also creates important by-products that are used in various cuisines.”
Production and taste:
“Regardless of the product or scale of the production, the production of tofu essentially consists of
1. the preparation of soymilk
2. the coagulation of the soymilk to form curds
3. the pressing of the soybean curds to form tofu cakes.
The typical tofu making procedures are cleaning, soaking, grinding beans in water, filtering, boiling, coagulation, and pressing. ...”
“Tofu flavor is generally described as bland, however this taste is desired by customers in North America while a more beany-flavor is preferred in East Asia. The beany or bland taste is generated during the grinding and cooking unit process during production and either a “hot grind” or “cold grind” can be implemented to influence the taste in line with taste preference.”
“Because it is made of soy, individuals with allergies, particularly those allergic to legumes, should not consume tofu.”
“Tofu-making was first recorded during the Chinese Han dynasty some 2,000 years ago.”