Home > Slow Cooker And Crockpot
Slow Cooker And Crockpot
A slow cooker, also known as a Crock-Pot (a trademark that is sometimes used generically in the US, Canada, Australia and New Zealand), is a countertop electrical cooking appliance that is used for simmering, which requires maintaining a relatively low temperature compared to other cooking methods such as baking, boiling and frying, allowing unattended cooking for many hours of pot roast, stews, soups, boiled dinners and other suitable dishes, including dips, desserts and beverages.
A basic slow cooker consists of a lidded round or oval cooking pot made of glazed ceramic or porcelain, surrounded by a housing, usually metal, containing an electric heating element. The lid is often of glass seated in a groove in the pot edge; condensed vapour collects in the groove and provides a low-pressure seal to the atmosphere. The contents of a crock pot are effectively at atmospheric pressure, despite the water vapour generated inside the pot. A crock pot is quite different from a pressure cooker and presents no danger of an abrupt pressure release.
The ceramic pot or "crock" acts as both a cooking container and a heat reservoir. Slow cookers come in capacities from 500 ml (17 US fl oz) to 7 L (7.4 US qt). Due to the placement of heating elements generally at the bottom and often also partway up the sides, there is usually a minimum recommended liquid level to avoid uncontrolled local heating. Many slow cookers have two or more heat settings e.g., low, medium, high and sometimes a "keep warm" setting; some have continuously variable power. Most slow cookers have no temperature control and deliver a constant heat to the contents. The temperature of the contents will rise 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.
Recipes intended for other cooking methods must be modified for slow cookers. Quantities of liquids may have to be adjusted as there is a little evaporation, but there should be enough liquid to cover the food. Many published recipes for slow cookers are designed primarily for convenience and use few ingredients, often prepared sauces and/or seasonings. The long, moist cooking is particularly suitable for tough and cheap cuts of meat including pork shoulder, beef chuck and brisket; for many slow-cooked dishes these cuts give better results than more expensive ones. They are also often used to cook while no one is there to care for it, meaning the cook can fill the pot with its ingredients and come back several hours later to a ready meal.
Cheaper cuts of meat with connective tissue and lean muscle fibre are suitable for stewing, and produce tastier stews than those using expensive cuts, as long slow cooking will soften the connective tissue without toughening the muscle. Slow cooking leaves the gelatinised tissue in the meat, so that it may be advantageous to start with a richer liquid. The low temperature of slow-cooking makes it almost impossible to burn food even if cooked too long. Food can be set to slow-cook before leaving for the day, and will be ready on return. Many homeowners with rooftop solar panels switch to slow cooking because its under-1KW load is low enough to be powered entirely by 1-2KW panels during the day. Some models include timers or thermostats which bring food to a given temperature, and then lower it. With a timerless cooker it is possible to use an external timer to stop cooking after a set time, or both to start and stop. Cooking the meal in a single pot reduces water waste resulting from cleaning multiple dishes, and the low cooking temperature and glazed pot make cleaning easier than conventional high-heat pots.
Some vitamins and other trace nutrients are lost, particularly from vegetables, partially by enzyme action during cooking and partially due to heat degradation. When vegetables are cooked at higher temperatures these enzymes are rapidly denatured and have less time in which to act during cooking. Since slow cookers work at temperatures well below boiling point and do not rapidly denature enzymes, vegetables tend to lose trace nutrients. Blanched vegetables, having been exposed to very hot water, have already had these enzymes rendered largely ineffective, so a blanching or sautéing pre-cook stage will leave more vitamins intact. This is often a smaller nutrient loss than over-boiling and can be lessened to an extent by not removing the lid until the food is done. Slow cookers do not provide sufficient heat to compensate for loss of moisture and heat due to frequent removal of the lid, e.g. to add and remove food in perpetual stews. Added ingredients must be given time to cook before the food can be eaten. Because of the longer cooking time, there is greater danger with slow cookers of having an extended power outage during cooking without the cook's knowledge; for example, the power may go out for several hours while the cook is away at work in places with unreliable power supply.