What is the chemical principle of tofu making?

Protein content in soybean is very high, and protein particles will gather together soon after brine. Brine Brine mainly contains magnesium chloride, and gypsum is calcium sulfate, so it becomes tofu brain. Squeeze the water out again, and the tofu brain will become tofu.

Adding brine to make tofu is a caking process, which is due to the neutralization of positive and negative charges, resulting in the decline of particle stability in turbid liquid.

South tofu is made of gypsum, and the solidified tofu flower is tender because of its high water content, with a water content of about 90%. Beidoufu is usually made of brine or sour sauce. The solidified tofu flower has less water content, and its texture is older than that of south tofu, with a water content of about 85%. However, due to less water content, tofu has a stronger taste, a tougher texture and is easier to cook.

Another is to add glucono-δ-lactone, which is called lactone tofu. This is a new coagulant. Compared with the traditional preparation method, it improves the yield and product quality, and reduces environmental pollution. The Japanese name is "silk tofu", and its texture is obviously smoother and more delicate than that of north tofu and south tofu.

Extended data:

Due to the different coagulants added in the production process, tofu is mainly divided into three categories:

The first is to add gypsum powder as coagulant, which is more common in the south. Because of the high water content, the solidified tofu flower is fresh and tender, and the water content is about 90%.

The second type is mostly made of brine or acid paste, which is more common in northern areas. The solidified tofu flower has less water content, and its texture is harder than that of southern tofu, with water content of 85%~88%. However, due to less water content, tofu tastes stronger, its texture is tougher and it is easier to cook.

The third is to add gluconic acid-δ-lactone, which is called lactone tofu. This is a new coagulant. Compared with the traditional preparation method, it improves the yield and product quality, and reduces environmental pollution. The Japanese name is "silk tofu", and its texture is obviously smoother and more delicate than that of north tofu and south tofu.

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