What is Pressure Cooking?
Pressure cooking is fun, fast, and easy— once you understand how it works.
Food and liquid are sealed into an airtight vessel, and no steam is released before the pre-set pressure is reached. The boiling point of water increases as the pressure increases, so pressure built up inside the cooker allows the liquid inside to boil at a temperature higher than 100°C / 212°F.
Pressure cooking is often used to simulate the effects of long braising or simmering, but in a much shorter period of time.
A Brief History of the Pressure Cooker
Believe it or not, the concept of pressure cooking has been around for over 350 years. The first known pressure cooker was invented by French physicist, Denis Papin, in 1679. However, pressure cooking only became popular during World War II, when people realized how much fuel could be saved by the quick cookers. Now, pressure cookers are a common household appliance, saving time and energy in the kitchen.
Conventional pressure cookers were designed to be used on a stovetop, with a steam regulator, safety valve and pressure-activated locking mechanism to provide protection against overheating and the risk of explosion. When a stovetop pressure cooker reaches the target pressure, the steam inside pushes the steam regulator up, which regulates excess pressure. This is why conventional pressure cookers generate that loud rattling noise when pressurized.
Inventing the Electric Pressure Cooker
The electric pressure cooker is an ingenious 20th century invention. Historians are divided about the specifics, but Chinese scientist, Yong-Guang Wang, filed the first electric pressure cooker patent on January 9th, 1991 (patent No. ZL91100026.7). This patent is currently owned by the world’s No. 1 electric pressure cooker manufacturer, Midea Group.
Electric pressure cookers consist of a pressure cooking container (inner pot), temperature & pressure sensors, and an electric heating element. Heating is controlled by a built-in microprocessor based on the readings of the pressure and temperature sensors. This whole process forms a “closed loop control system” in control engineering terms, a principle similar to cruise-control in cars.
Essentially, the cook puts all the ingredients into the inner pot, and specifies the pressure cooking duration—the electric pressure cooker does the rest!
The Next Generation
Over time, leading manufacturers began developing cooking “profiles”. By using various combinations of temperature, pressure and cooking time, pre-set programming emerged for simmering, steaming, braising, slow cooking, warming, and rice cooking. This enhancement lead to the next generation of electric pressure cookers: “3rd generation” programmable smart cookers.
Learn more about how electric pressure cookers work.