Protein-rich animal raw materials are often used in soup, preferably cattle, sheep, pig bones and chicken and duck bones. The method is as follows: firstly, wash the raw materials, add enough cold water once, boil with strong fire, then switch to low fire for 20 minutes, skim off the foam, add ginger, cooking wine and other seasonings, boil the water again, and continue to cook for 3-4 hours with medium fire, so that protein in the raw materials can be dissolved more, and the soup is thick and milky. After cooling, it can be regarded as the boiled soup.

Many people like to cook soup with a small fire for a whole day, thinking that the nutrition of food can be fully dissolved in the soup. In fact, there is no scientific basis for this practice. Studies have proved that a moderate extension of cooking time is indeed helpful to the release and absorption of nutrients, but too long time will cause certain damage to nutrients.