A slow cookeralso known as a crock-pot after a trademark owned by Sunbeam Products but sometimes used generically in the English-speaking worldis a countertop electrical cooking appliance used to simmer at a lower temperature than other cooking methods, such as baking, boiling, and frying.
Slow cookers achieved popularity in the US during the s, when many women began to work outside the home. The Rival Company from Sedalia, Missouri, bought Naxon inacquiring Naxon's patent for the bean simmer cooker. Martin also designed and produced the mass-production machines for Rival's manufacturing line of the Crock-Pot.
The cooker was then reintroduced under the name "Crock-Pot" in The Crock-Pot brand now belongs to Newell Brands. A basic slow cooker consists of a lidded round or oval cooking pot made of glazed ceramic or porcelainsurrounded by a housing, usually metal, containing an electric heating element.
The lid itself is often made of glass, and seated in a groove in the pot edge; condensed vapor collects in the groove and provides a low-pressure seal to the atmosphere. The contents of a crock pot are effectively at atmospheric pressuredespite the water vapor generated inside the pot.
A slow cooker is quite different from a pressure cooker and presents no danger of an abrupt pressure release. The " crock ", or ceramic pot, itself acts as both a cooking container and a heat reservoir. Slow cookers come in capacities from mL 17 US fl oz to 7 L 7.
Because the heating elements are generally located at the bottom and often also partway up the sides, most slow cookers have a minimum recommended liquid level to avoid uncontrolled heating. Some newer models have coated aluminum or steel "crocks" which, while not as efficient as ceramic at retaining heat, do allow for quicker heating and cooling as well as the ability to use the "crock" on the stove top to brown meat prior to cooking.
Many slow cookers have two or more heat settings e. In the past, most slow cookers had no temperature control and deliver a constant heat to the contents. The temperature of the contents rises until it reaches boiling point, at which point the energy goes into gently boiling the liquid closest to the hot surface.
At a lower setting, it may just simmer at a temperature below the boiling point. While many basic slow cookers still operate in this manner, newer models have computerized controls for precise temperature control, delayed cooking starts and even control via a computer or mobile device.
To use a slow cooker, the cook places raw food and a liquid, such as stockwater, or wine, in the slow cooker. Some recipes call for pre-heated liquid. The cook puts the lid on the slow cooker and turns it on. Some cookers automatically switch from cooking to warming maintaining the temperature at 71—74 °C — °F after a fixed time or after the internal temperature of the food, as determined by a probe, reaches a specified value.
The heating element heats the contents to a steady temperature in the 79—93 °C — °F range. The contents are enclosed by the crock and the lid, and attain an essentially Mat och Bakning temperature. The vapor that is produced at this temperature condenses on the bottom of the lid and returns as liquid, into which some water-soluble vitamins are leached.
The liquid transfers heat from the pot walls to its contents, and also distributes flavors. The slow cooker's lid is essential to prevent the warm vapor from escaping, taking heat with it and cooling the contents.