The division between acidic food and alkaline food is determined by the pH value of inorganic salts left in the body after digestion, rather than directly detecting the pH value of food.

For example, foods rich in protein are digested to form acids such as nitrogen, carbon, sulfur, chlorine and salt, which are called acidic foods. Acidic foods in daily life mainly include cattle, sheep, pigs, chickens, ducks, fish, grains, egg yolks, white rice, shrimp, brown rice, bread, broad beans, beer, flour, peanuts, fried tofu, dried laver and so on.

Acidic foods are as follows:

1. Strongly acidic food: egg yolk, cheese, dessert, white sugar, tuna, flounder, cheese, western-style cakes, persimmon cakes, mullet roe, chaiyu, etc.

2. Acidic food: sausage, bacon, chicken breast, raw pork, squid, beef and mutton, toast, wheat, tuna, beef and mutton, toast, wheat, fresh cream, horse meat, etc.

3. Weakly acidic foods: chocolate, hollow powder, onion, sorghum, peanut kernel, wine, fried tofu, seaweed, clams, squid, loach fish, etc.