Chengzhijin vacuum health pot is actually an ordinary imitation die-casting aluminum pot with ceramic coating and a glass cover with a silicone ring, which gives it a nice name. The main principle is that after the vegetable soup is cooked, the vent hole of the cover is closed. Because the temperature in the pot drops, the air in the pot cools and contracts, and the air pressure in the pot is lower than the external atmospheric pressure. Because of the negative pressure, the so-called vacuum, the boiling point of the liquid in the pot is lower than 100 degrees and continues to boil. It's hard to say whether the coating is poisonous or not. Because the paint made of golden yellow toner is difficult to pass the inspection of EU FDA and LFGB. At present, there are many factories producing ceramic coatings in China, but at the same time, the quality of each batch of products is mixed, and it is difficult to guarantee whether the ingredients are qualified or not.