Al About Instant Pots

It seems that everyone has one of these electric pressure cookers hanging out on their counters. But what even is an Instant Pot?

History of Pressure Cookers

In the 1670s, French physicist and mathematician named Denis Papin invented the“steam digester,” the precursor to both the pressure cooker and the steam engine. The device was designed to extract fats and collagen from bones and ground the bones into meal. The steam digester consisted of a closed pot with a tight-fitting lid. As food and water heated up, the vessel trapped steam, raising the pot's internal pressure. In the 1930s, Alfred Vischer created the “Flex-Seal Speed Cooker” as the first pressure cooker for the home kitchen.

Science of Pressure Cookers

The pressure cooker can be best explained by the “ideal gas law” (or “general gas equation”), which describes the behavior of most gases under most conditions. It is commonly given as: PV = nRT. P stands for pressure, V stands for volume, T stands for temperature, n represents the amount of a given gas ,and R represents a constant. In the pressure cooker, V and R does not change. As the pressure cooker heats food up, T goes up.

As the system heats up, there is more energy supplied to molecules of water vapor, which causes them to bounce around and collide randomly both with each other and against the walls of the container. The force of these collisions against the walls is one definition of pressure.