Slow cooker
A slow cooker, also known as a crock-pot (after a trademark owned by
History
Slow cookers achieved popularity in the US during the 1940s, when many women began to work outside the home.[2] They could start dinner cooking in the morning before going to work and finish preparing the meal in the evening when they came home.
The Naxon Utilities Corporation of
Other brands of this appliance include
, and the now defunct American Electric Corporation.Design
A basic slow cooker consists of a lidded round or oval
The "
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. 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 control via a computer or mobile device.
Operation
To use a slow cooker, the cook places raw food and a liquid, such as stock, water, 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 (160–165 °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 (174–199 °F) range. The contents are enclosed by the crock and the lid, and attain an essentially constant temperature. The vapor that is produced at this temperature
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.
Basic cookers, which have only high, medium, low, or keep warm settings, must be turned on and off manually. More advanced cookers have computerized timing devices that let a cook program the cooker to perform multiple operations (e.g., two hours high, followed by two hours low, followed by warm) and to delay the start of cooking.
Because food cooked in a slow cooker stays warm for a long time after it is switched off, people can use the slow cookers to take food elsewhere to eat without reheating. Some slow cookers have lids that seal to prevent their contents from spilling during transport.
Recipes
Recipes intended for other cooking methods must be modified for slow cookers. Quantities of liquids may need adjustment, as there is a little
Advantages
Cheaper cuts of meat with
The low temperature of slow-cooking makes it almost impossible to burn even food that has been cooked too long. However, some meats and most vegetables become nearly tasteless or "raggy" if over-cooked.
Food can be set to slow-cook before leaving for the day so it is ready on return. Many homeowners with
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.
Disadvantages
Some vitamins and other trace nutrients are lost, particularly from vegetables, partially by enzyme action during cooking and partially due to heat degradation.[citation needed] When vegetables are cooked at higher temperatures these enzymes are rapidly denatured and have less time 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.[citation needed] Blanched vegetables, having been exposed to very hot water, have already had these enzymes rendered largely ineffective, so a blanching or sauteing pre-cook stage leaves more vitamins intact.[9] 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, (pot-au-feu, olla podrida). Added ingredients must be given time to cook before the food can be eaten.
Hazards
Scalding
Slow cookers are less dangerous than ovens or stove tops due to their lower operating temperatures and closed lids. However, they still contain a large amount of foods and liquids at temperatures close to boiling, and they can cause serious scalds if spilled.
Poisoning concerns
Slow cookers should not be used to cook dried kidney beans and other legume seeds.[10] These foods contain the highly toxic lectin phytohemagglutinin,[11] making as few as four raw beans toxic.[12] This lectin is only deactivated by long soaking, then boiling in fresh water at 100 °C (212 °F) for at least thirty minutes.[13] Information published by the United States Food and Drug Administration states that slow cookers should not be used to cook bean containing dishes.[14] Commercially canned beans are fully cooked and are safe to use. Pressure cooking also deactivates the lectins.[15]
See also
- Beanpot
- Carry over cooking
- Combi steamer
- Haybox
- List of cooking appliances
- Low-temperature cooking
- Rice cooker
- Remoska
- Sous-vide
- Thermal cooking
References
- ^ Gisslen, Wayne (2011). Professional cooking, 7th ed., John Wiley & Sons, Inc. p. 71
- ^ a b c d e Delgado, Michelle (26 November 2019). "A Brief History of the Crock Pot". Smithsonian. Retrieved 15 December 2019.
- ^ Naxon, Lenore. "My Dad, the Inventor of the Crock Pot". Archived 2013-06-14 at the Wayback Machine. Beyond Bubbie. 8 April 2013. 2 May 2013.
- ^ Pilkington, Katie (January 31, 2014). "From humble to high tech, a slow cooker history". CNET. Retrieved December 29, 2016.
- ^ The Rotarian. April 1950. p. 2. Retrieved 2016-11-27.
- ^ the Editors of Easy Home Cooking Magazine . "HowStuffWorks". Recipes.howstuffworks.com. Retrieved 2010-02-09.
- ^ Blumenthal, Heston (7 December 2002). "Take your time | Life and style". The Guardian. Retrieved 9 February 2010.
- ^ Christie, Sophie (22 November 2013). "How much cheaper is a slow cooker than an oven?". The Daily Telegraph. Retrieved 5 December 2016.
- ^ "National Center for Home Food Preservation". University of Georgia. Retrieved 2010-02-10.
- ^ "Bad Bug Book (2012)" (PDF). Foodborne Pathogenic Microorganisms and Natural Toxins Handbook: Phytohaemagglutinin. Food and Drug Administration. 2012. Retrieved 9 May 2022.
Slow cookers should not be used to cook these beans or dishes that contain them. Studies of casseroles cooked in slow cookers revealed that the food often reached internal temperatures of only 75°C or less, which is inadequate for destruction of the toxin.
- ^ "Bad Bug Book (2012)" (PDF). Foodborne Pathogenic Microorganisms and Natural Toxins Handbook: Phytohaemagglutinin. Food and Drug Administration. 2012. Retrieved 2 February 2022.
Among the lectins known to have toxic effects is phytohaemagglutinin which occurs at relatively high levels in the seeds of legumes eg beans
- ^ "Bad Bug Book (2012)" (PDF). Foodborne Pathogenic Microorganisms and Natural Toxins Handbook: Phytohaemagglutinin. Food and Drug Administration. 2012. Retrieved 2 February 2022.
Toxic dose: As few as four or five raw beans can trigger symptoms.
- ^ "Bad Bug Book (2012)" (PDF). Foodborne Pathogenic Microorganisms and Natural Toxins Handbook: Phytohaemagglutinin. Food and Drug Administration. 2012. Retrieved 2 February 2022.
Studies done by British scientists suggest that beans should be soaked in water for at least 5 hours,the water poured away, and the beans boiled in fresh water for at least 30 minutes
- ^ "Bad Bug Book (2012)" (PDF). Foodborne Pathogenic Microorganisms and Natural Toxins Handbook: Phytohaemagglutinin. Food and Drug Administration. 2012. Retrieved 9 May 2022.
Slow cookers should not be used to cook these beans or dishes that contain them. Studies of casseroles cooked in slow cookers revealed that the food often reached internal temperatures of only 75°C or less, which is inadequate for destruction of the toxin.
- ^ Kotifani, Aislinn (2020-03-06). "The Truth About Lectins—Why Beans Have Gotten a Bad Rap - Blue Zones". Blue Zones. Retrieved 2022-05-10.
Further reading
- Hugh Acheson (2017). The Chef and the Slow Cooker. Clarkson Potter. ISBN 978-0451498540.