Old tofu, young tofu, and lactofermented tofu are all made from soybeans, but the coagulants used in the production process are different.

The old tofu, also called north tofu, salt brine as a coagulant, pressed part of the water into the finished product made of tofu with less water, hardness, toughness and elasticity, the color of the white yellow, suitable for frying, deep-frying, stuffing, braising and other dishes. Old tofu is northern tofu, also known as "brine tofu", brine (magnesium chloride) as a coagulant, calcium and magnesium ions inside the combination of soy protein coagulation reaction, so that the tofu molding. After molding, the tofu is also pressed with a heavy weight for about 30 minutes to further drain it and make it firm and flexible. This is why older tofu is harder and has a rougher texture.

Tender tofu, also known as southern tofu, uses gypsum powder as a coagulant, contains more water than northern tofu, and has a fluffy texture and creamy color, making it suitable for making soups and other dishes.

The inner fat tofu, with β-gluconolactone as the coagulant, has a more delicate texture than southern tofu, and the process of making inner fat tofu is simple and can be easily operated at home. The advantages of inner fat tofu are that it reduces protein loss, improves water retention and increases yield, and the tofu is white, delicate, shiny, tasty and has a long shelf life.

Lactone tofu uses something called "gluconolactone" as a coagulant, which triggers a slower coagulation process. Soymilk is usually sterilized at ultra-high temperatures, and then added to gluconolactone before being sealed in a box. The tofu obtained this way has a longer shelf life.

Tender tofu does not need to be pressed after molding, and contains higher moisture for a more tender taste.

Older tofu has a tighter texture, more solid organization, yellowish color, not easy to break, and a bit more solid taste, while tender tofu is delicate and smooth, white in color, with a texture closer to soya bean curd, which is easy to break, and has a soft and tender taste that melts in your mouth.

Old tofu recipes: fried tofu with salt and pepper

Tender tofu recipes: steamed tofu with minced pork, seaweed and tofu soup

Lactone tofu recipes: steamed egg with shrimp and tofu