What's Important To Know About Pressure Cookers

Denis Pain, a French physicist invented the pressure cooker in 1679, at that time they were called steam digesters. They were also called many other names, but that was the original name. Slowly over time it became known as a pressure cooker. Then they started making pressure cookers in the United States, sometimes called pressure canners, with a large capacity which was able to hold jars for canning at home. 

An autoclave, also known as a big pressure cooker is used in hospitals and laboratories to sterilize materials. In the food industry pressure cookers are called retorts. So there are many different names used for pressure cookers however the design is basically the same. Most are made from stainless steel or aluminum. The best ones are made of stainless steel as they last longer. 

Pressure cookers are usually buffed, stamped, anodized and can be put in the dishwasher for cleaning. Some manufactures recommend hand washing your pressure cooker. High quality pressure cookers are made with heavy, three-ply or copper clad bottoms for spreading the heat evenly. 

There is a sealing ring or gasket that forms a gas-tight seal which does not allow air or steam to escape the stainless steel pressure cookers. When the pressure builds up, the only way the steam can escape is through the regulator on the lid. If the regulator happens to get stopped up, there is a safety valve that provides backup for the steam to be released. If by chance the pressure exceeds the design limit, the plug pops out of its seat. 

Larger pressure cookers that are used at home have oval oversized lids. Since the lid is larger than the opening one will insert the lid at an angle, and then align the top of the cooker, holding the lid in place. The pressurized steam inside the cooker keeps the lid in place, preventing accidental removal of the lid. 

Pressure cookers are heavy; they have to be because of the pressure they hold. There are some pressure cookers for camping that are very light maybe 1.2 kg for the four-liter pot. 

To cook at home with a pressure cooker is quite simple. Just put the food you want to cook into the pot and add a little bit of water. Put the lid on tightly turning the lid until it clicks. Select the pressure setting, some use a weight placed on the steam vent. Place the pressure cooker on the highest heat. (Usually the stove top.) When the pressure cooker reaches full pressure, just turn down the heat and time the recipe. The relief valve opens and starts to steam. 

Stainless steel cookers have a reputation as being very dangerous, they can explode and food goes everywhere. Early ones were known to do that. But today’s pressure cookers are much safer as they have two or three extra safety valves or regulators that prevent explosions.