From the Jin Dynasty to the Tang Dynasty, mocking a person's lack of good upbringing and ignorance of upper-class hygiene habits, he would often say that he does not know bath beans  Bath bean is a high-grade sanitary and cleaning product invented in Wei, Jin, Southern and Northern dynasties  Previously, when people washed, the only ways to remove oil were rice soup, noodle soup and natural soap horn
Bath beans are made from a variety of beans as the main material, using the natural oil removal properties of beans to clean the skin
Ordinary people seldom use bath beans