Pressure cooker, also called pressure cooker, is a kind of kitchen utensil. The boiling point of the liquid in the pressure cooker at a higher pressure will enhance this physical phenomenon, so that the water can reach a higher temperature without boiling, so as to speed up the efficiency of stewing food. It can be used to heat the cooked food to more than 100 ℃. In high altitude areas, the use of pressure cooker can avoid the problem of reducing the boiling point of water and making it difficult to cook food.

The principle of pressure cooker is very simple, because the boiling point of water is affected by the air pressure. The higher the air pressure, the higher the boiling point. On high mountains and plateaus, the air pressure is less than 1 standard atmospheric pressure, and the boiling point of water is lower than 100 ℃, so water can boil under 100 ℃. Eggs are not cooked with ordinary pots. When the air pressure is greater than 1 atmosphere, the water will not boil until the temperature is higher than 100 ℃. The commonly used pressure cooker is designed based on this principle.