1. Different production principles (1) Lactone tofu: tofu produced with gluconic acid-δ-lactone as coagulant. The traditional method of making tofu with brine is changed, which can reduce the loss of protein. (2) Brine tofu: It is made of crystallized magnesium chloride aqueous solution, also called bittern tofu, because crystallized magnesium chloride aqueous solution is commonly known as bittern. Gypsum tofu is made of gypsum water formed by calcium sulfate (gypsum). Brine, as coagulant, has complex technology, low yield, short storage period and is not easily absorbed by human body.

2. Different tastes: (1) Lactone tofu: Tofu is tender, shiny, palatable, clean and hygienic. (2) Brine tofu: The taste of brine tofu is soft and tough, and it feels hard to eat because it has less water content. Brine tofu tastes like beans, and its color looks slightly yellow in white. The texture of brine tofu is coarse and old, commonly known as "old tofu" and "north tofu".

3. Different nutritional values (1) Lactone tofu: tofu is sweet, light and cool, and enters the spleen, stomach and intestines; Beneficial to middle qi, harmonizing spleen and stomach, invigorating spleen and promoting diuresis, clearing away lung-heat, strengthening skin, clearing away heat and toxic materials, lowering qi and eliminating phlegm; Can be used for abdominal distension, hematemesis and vomiting caused by acclimatization due to spleen and stomach weakness; Moistening dryness and promoting fluid production, used to quench thirst, lack of milk and other diseases; Used for sulfur and soju poisoning. (2) Brine tofu: It contains minerals such as copper and calcium, which have an important influence on the development and function of blood, central nervous system and immune system, hair, skin and bone tissues, brain, liver, heart and other internal organs. It also contains substances such as carbohydrates and protein, which can improve immunity. Lowering blood pressure and buffering anemia are beneficial to growth and development. Boil in clear water for 1 minutes. Drinking water and eating tofu can relieve cough, especially for habitual cough.