Pressure cooker can heat the cooking food to a temperature of above 100 ℃, it is invented in 1679 by French physicist Pa level. Its unique high temperature and high pressure functions has greatly shorten the cooking time, saving energy; relatively large pressure cooker has big destruction for the food nutrition. Frenchman Denis Papin (1647-1712), worked as the Huygens assistant. In 1675, Papin came to Britain with Robert ? Bolivian justice ears to work together. In 1680, he was elected to the Royal Society. In 1681, he wrote the essay to introduce digester. "Cooking" is a device in sealed containers used boiled water to cook bones until it is softening. As we now know, boiled water under high pressure has high boiling point, and thus enhance the dissolving power of water.
Working Principle of Pressure Cooker
The principle is very simple in the pressure cooker, because the boiling point of water is affected by air pressure, the higher the air pressure, the higher the boiling point. In the mountains and on the plateau, the air pressure is less than 1 ATM, water can boil at the pressure less than 100 ℃, eggs cannot be cooked to eat with ordinary cookware. When a pressure is greater than atmospheric pressure, the water will boil when the pressure is higher than 100 ℃. The now commonly used pressure cookers are designed in the use of this principle. Autoclave the water relatively tightly closed, water heated to evaporate water vapor generated cannot be diffused in the air, can only be retained in the autoclave, the internal pressure of the autoclave is higher than an atmospheric pressure, but also that the water should be higher than 100 ℃ when boiling. Now in many rural areas, the pressure cooker is still one of the most basic home kitchen appliances.
Pressure Cooker Characteristics
The ordinary aluminum pressure cooker is light in weight, fast in heating, cheap in price, the surface of the small pressure cookers has the anti-corrosion alumina layer, it can be rapidly cooling with cold water, as per the life is 1 hour per day, the life can reach eight years, and is not suitable for induction cooker. The stainless steel composite bottom aluminum pressure cooker is just like the stainless steel pressure induction cooker, it has the ordinary aluminum pressure cooker advantages, but one thing should be keep in mind that it must keep away from fires. Stainless steel pressure cooker is expensive, heat-resistant, beautiful, and according to one hour a day, the useful life is about 10 years, suitable for induction cooker and gas stove.
The article is come form:http://www.chinanon-woven.com/?p=5