View source for Rice cooker

{{primary sources|date=September 2023}}

{{Short description|Kitchen appliance}}
{{about|automated rice-cooking appliances|less automated methods of cooking rice|rice-cooking utensils|the car and motorcycle term|Rice burner}}
[[File:Rice Cooker 1.png|thumb|right|Electric induction rice cooker with scoop]]
A '''rice cooker''' or '''rice steamer''' is an automated [[kitchen appliance]] designed to boil or steam [[rice]]. It consists of a heat source, a cooking bowl, and a thermostat. The thermostat measures the temperature of the cooking bowl and controls the heat. Complex, high-tech rice cookers may have more sensors and other components, and may be multipurpose.

The term ''rice cooker'' formerly applied to non-automated dedicated [[rice-cooking utensils]], which have an ancient history (a ceramic rice steamer dated to 1250 BC is on display in [[the British Museum]]). It now applies mostly to automated cookers. Electric rice cookers were developed in [[Japan]], where they are known as ''[[jp:炊飯器|suihanki]]'' ({{langx|ja|炊飯器}}, literally, "boil-rice-device").<ref name="atlas"/>

==History==
[[File:Electric Rice Cooker 1956.jpg|thumb|A 1956 advertisement for [[Toshiba]]'s world's first automatic electric rice cooker, priced at 3,200 yen and capable of cooking {{convert|900|g|lb}} of rice.]] The NJ-N1, developed by [[Mitsubishi Electric]] in 1923, was the first electric rice cooker, a direct ancestor of today's automatic electric rice cookers. At that time, electricity was not widely used in ordinary households; it was for use on ships.<ref name="atlas">{{cite web|url=https://www.atlasobscura.com/articles/rice-cooker-history/|archive-url=https://web.archive.org/web/20230509155150/https://www.atlasobscura.com/articles/rice-cooker-history/|last=Ewbank|first=Anne|title=The Battle to Invent the Automatic Rice Cooker|publisher=Atlas Obscura|date=31 July 2020|archive-date=9 May 2023|access-date=5 June 2023}}</ref><ref>{{cite web|url=https://www.goodspress.jp/columns/67395/2/|archive-url=https://web.archive.org/web/20220707005410/https://www.goodspress.jp/columns/67395/2/|script-title=ja:【プロダクトヒストリー】炊飯器～連続沸騰で美味しさが進化～|language=ja|publisher=[[Tokuma Shoten]]|date=20 November 2016|archive-date=7 July 2022|access-date=5 June 2023}}</ref> It was a simple mechanism that heated with an attached heating coil without automation.<ref name ="toshibae">{{cite web|title=Toshiba Firsts Of Their Kind|url=http://museum.toshiba.co.jp/toshiba_history/firsts_products/1955rice.html|url-status=dead|archive-url=https://web.archive.org/web/20111005142830/http://museum.toshiba.co.jp/toshiba_history/firsts_products/1955rice.html|archive-date=2011-10-05|access-date=2010-03-14|publisher=Toshiba Corp. Museum}}</ref>

In the 1940s and early 1950s, Mitsubishi Electric, Matsushita Electric (now [[Panasonic]]), and [[Sony]] introduced electric rice cookers for home use with built-in heating coils, but they too were not automated and were not well received and sold poorly.<ref name ="toshibae"/>

The ER-4,<ref>{{cite web|url=http://digioka.libnet.pref.okayama.jp/detail-jp_c/id/ref/M2019030815352504951|archive-url=https://web.archive.org/web/20230605095226/http://digioka.libnet.pref.okayama.jp/detail-jp_c/id/ref/M2019030815352504951|title=自動炊飯器の歴史|publisher=Okayama Prefectural Library|archive-date=5 June 2023|access-date=5 June 2023}}</ref><ref name="toshibaer">{{Cite web|title=IH Jar Rice Cooker: The Special Duty-Free Website Toshiba Living Doors|url=https://www.toshiba-lifestyle.co.jp/living/tourist/en/special/index_j.htm|archive-url=https://web.archive.org/web/20230425133822/https://www.toshiba-lifestyle.com/jp/living/tourist/en/special/index_j.htm|archive-date=25 April 2023|access-date=5 June 2023|website=www.toshiba-lifestyle.co.jp}}</ref> introduced by [[Toshiba]] on December 10, 1955<ref name="toshibaer"/><ref name="toshiba"/><ref name="all2"/> (or 1956<ref name ="toshibae"/>), was the world's first automatic electric rice cooker for home use. It was developed by Toshiba's Shogo Yamada beginning in 1951 and completed in 1955 thanks to a breakthrough invention by Yoshitada Minami ([[:ja:三並義忠|ja]]), president of a Toshiba partner company.<ref name="atlas"/><ref name ="toshibae"/><ref name="toshiba">{{cite web|url=https://toshiba-mirai-kagakukan.jp/history/ichigoki/products.htm|archive-url=https://web.archive.org/web/20230320121800/https://toshiba-mirai-kagakukan.jp/history/ichigoki/products.htm|script-title=ja:日本初の自動式電気釜|language=ja|publisher=Toshiba Science Museum|archive-date=20 March 2023|access-date=5 June 2023}}</ref><ref name="all2">{{cite web|url=https://allabout.co.jp/gm/gc/292625/2/|archive-url=https://web.archive.org/web/20150821053810/https://allabout.co.jp/gm/gc/292625/2/|author=Katsumi Kimura|script-title=ja:台所革命！世界初の電気炊飯器の誕生物語2|language=ja|publisher=All About, Inc.|date=29 March 2006|archive-date=21 August 2015|access-date=5 June 2023}}</ref> Research and development was a continuous process of trial and error. Research showed that rice cooks best when cooked at a temperature of {{convert|98|C|F}} for 20 minutes, so theoretically rice should cook well if an automatic timer is set to turn off the cooker 20 minutes after the water in the pot has boiled. However, the time it takes for the water to boil varies depending on the temperature, the amount of heat generated by the pot, and the amount of rice and water, so in the prototype stage, sometimes the rice was overcooked and burnt, while at other times it was undercooked and the rice was left with a core. The revolutionary idea to solve this problem was to use a double-layered structure for the pot. The mechanism involved filling the outer pot with a glass of water and heating it. After about 20 minutes, the water would evaporate and the temperature would rise rapidly, which the thermostat would detect and turn off.<ref name ="toshibae"/><ref name="toshiba"/><ref name="all2"/><ref name="atlas"/>

The initial launch price was 3,200 yen, about one-third of the average college graduate's starting monthly salary.<ref name="all2"/> At its launch, 700 units were produced, but they did not sell well.
The company then conducted sales promotions using the sales networks of electric power companies, held sales demonstrations, and sold an automatic timer that could turn on the rice cooker at any time, and the product's popularity exploded. By 1960, four years after its introduction, the automatic electric rice cooker was in use in about half of all Japanese households.<ref name="all3">{{cite web|url=https://allabout.co.jp/gm/gc/292625/3/|archive-url=https://web.archive.org/web/20210725082352/https://allabout.co.jp/gm/gc/292625/3/|author=Katsumi Kimura|script-title=ja:台所革命！世界初の電気炊飯器の誕生物語3|language=ja|publisher=All About, Inc.|date=29 March 2006|archive-date=25 July 2021|access-date=5 June 2023}}</ref><ref name="toshiba"/>

The success of Toshiba's automatic electric rice cookers sparked a "manufacturing war", and Matsushita Electric entered the field as early as 1956 with the EC-36. The EC-36 was a cheaper product that used a single pot, reducing the amount of metal used and making it more competitive in terms of sales.<ref name="atlas"/>

Later, the automatic electric rice cooker was well received in Asian countries and around the world under the name "Automatic Rice Cooker". It also had a great impact on society, giving housewives more time and accelerating the [[women's liberation movement]].<ref name="all3"/> On the other hand, Helen Macnaughtan argued that the invention of the automatic electric rice cooker, which freed women from menial tasks in the kitchen and allowed some women to work part-time, was not a great victory for women's liberation because it gave them more time to devote to other household tasks.<ref name="atlas"/> Rice cookers made their way to the American market via [[Hawaii]] and [[California]]'s Asian demographics in the 1950s, and especially [[Louisiana]] with the sale of Hitachi models since in the 1970s befitting the prevalence of rice dishes in its [[Cajun cuisine]].<ref>{{cite news  |first=Jordan LaHaye |last= Fontenot |title=Hitachi: How the rice cooker became a staple of Acadiana food culture |url=https://www.countryroadsmagazine.com/cuisine/Louisiana-foodways/hitachi-rice-cooker-in-Acadiana_1/ |magazine=Country Roads Magazine |date=22 June 2023 }}</ref>

In 1972, a rice cooker with a heat-retention function was introduced, and in 1979, an electronic rice cooker equipped with a [[microcomputer]] that could also manage the soaking of rice after washing and the heat level. In 1988, rice cookers with electromagnetic [[induction heating]] were introduced, which provided higher heating.<ref name="all3"/>

==Principle of operation==
[[File:Rijstkoker.jpg|thumb|right|Traditional rice cooker commonly used in the Netherlands by residents of the former [[Dutch East Indies]] (now: [[Indonesia]]) in the 1950s. Showcase on display at the Eurasian festival ''[[Tong Tong Fair]]'' 2012.]]
[[File:Hezery99-Gas rice cooker.jpg|thumb|A typical commercial gas cooker. To use it, the left lever is depressed to ignite the pilot burner for standby and keep-warm purposes. To start cooking, the right lever is pushed to operate the main burner, which is ignited by the pilot burner. Like its electric counterpart, the cook lever releases automatically once the rice is fully cooked.]]
[[File:Electric Rice Cooker.png|thumb|left|Basic principle of electric rice cooker operation]]

A basic rice cooker has a main body (pot), an inner cooking container which holds the rice, an electric [[heating element]], and a [[thermostat]].<ref> {{cite patent
| country       =US
| number        =USD984195S1
| title         =Electric rice cooker
| pubdate       =2023
|inventor1-last=Mao
|inventor1-first=Tan
| url = https://patents.google.com/patent/USD984195S1/en
}} </ref>

The bowl is filled with rice and water and heated at full power; the water reaches and stays at [[boiling point]] (100&nbsp;°C, 212&nbsp;°F).<ref name=hsw>{{cite web |url=https://home.howstuffworks.com/rice-cooker1.htm |title=Rice Cooker Basics |website=How Stuff Works|date=4 April 2008 |access-date= 10 February 2019}}</ref> When the water has all been absorbed, the temperature can rise above boiling point, which trips the thermostat. Some cookers switch to low-power "warming" mode, keeping the rice at a safe temperature of approximately 65&nbsp;°C (150&nbsp;°F); simpler models switch off; the rice has entered the resting phase.

Rice cookers are usually sold with a [[rice paddle]] and a measuring cup included.  The measuring cup is typically 180&nbsp;ml or roughly one ''[[gō (unit)|gō]]'', a [[Japanese units of measurement|traditional Japanese unit]] of volume.

More advanced cookers may use [[fuzzy logic]] for more detailed temperature control, [[Induction heating|induction]] rather than resistive heating, a steaming tray for other foods, and even the ability to rinse the rice.<ref name=hsw/>


<!--
<imagemap>
File:Rice_Cooker_115V.svg|frameless|right|thumb|upright=2.5|Rice Cooker 115V
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rect 123 934 181 971 [[Switch]]
rect 932 803 992 850 [[thermal fuse]]
rect 191 967 361 1053 [[indicator lamp|This indicator lamp is on when the power is connected and the heater is off.]]
rect 513 971 682 1053 [[indicator lamp|This indicator lamp is on when the heater is on.]]
rect 288 710 585 797 [[Heating element|Some cookers use two heater elements for 115 volts each. When configured to 115 volts power, the heaters are wired parallel, for 230 volts power, the heaters are wired in series.]]
rect 797 719 1088 797 [[Heating element|Some cookers use two heater elements for 115 volts each. When configured to 115 volts power, the heaters are wired parallel, for 230 volts power, the heaters are wired in series.]]
rect 1035 994 1093 1043 [[Fuse (electrical)|fuse]]
rect 593 719 789 770 [[magnet|This permanent magnet was selected by its curie temperature. When cooking the rice finished, the bottom heats up due missing water and makes the magnet reach its curie temperature. This causes the release of the lever and the spring pushes back the lever making the heater turn off by turning the switch.]]
rect 1206 941 1341 1051 [[IEC 60320|power input jack]]
rect 1238 259 1288 287 [[:File:Rice Cooker 230V with keep warm option.svg|The trough collects condensed water.]]
rect 774 821 774 821 [[Spring (device)|This spring pushes the magnet in its aluminum cover to the bottom of the pot, retrieving its temperature. When the pot is removed or empty, it should lift it and remove the magnet from the lever turning off the heater.]]
rect 600 766 782 829 [[Spring (device)|This spring pushes the magnet in its aluminum cover to the bottom of the pot, retrieving its temperature. When the pot is removed or empty, it should lift and remove the magnet from the lever turning off the heater.]]
rect 600 830 782 918 [[Curie temperature|This spring pulls the lever from the magnet when the magnet loses its magnetism by reaching its curie temperature. It is far enough not to enable the magnet to pull the lever again, when the temperature drops and the magnetism of the magnet returns by cooling below its curie temperature.]]
poly 1206 542 1208 610 1197 649 1173 670 1130 694 253 694 209 674 189 649 175 622 177 538 [[rice|This is the maximum level to fill rice into the pot.]]
rect 175 405 1210 542 [[water|When the uncooked rice is in the pot, water is filled to this level over the rice.]]
rect 910 1054 994 1121 [[Drain (plumbing)|If water enters the area with the electric components, it drains off here.]]
rect 957 64 1041 292 [[steam|Steam is released here.]]
rect 440 19 945 131 [[handle|With the handle, the empty cooker can be moved or the top lifted to open.]]
rect 1257 191 1325 244 [[Hinge]]
rect 12 483 109 610 [[Pushbutton|Pushing or drawing down this button, the heater is turned on, pulling it up, the coocker should turn off. It is fixed to the lever.]]
rect 2 203 127 277 [[lock button|This button releases the top of the cooker to open it.]]
rect 585 125 770 275 [[Spring (mathematics)|This spring closes the pot to keep the steam exit to the hole only. On overpressure it releases.]]
rect 304 846 345 893 [[protective ground|All touchable conduction parts required to be connected to the protective ground to prevent hazards on electrical failure.]]
desc bottom-right
</imagemap>-->

=== Rice types and rice cookers ===

[[Brown rice]] generally needs longer cooking times than [[white rice]], unless it is [[broken rice|broken]], or flourblasted (which perforates the bran).<ref name=AR2002>[http://www.ars.usda.gov/is/AR/archive/may02/rice0502.htm ars.usda.gov Agriculture Research, May 2002]</ref>

Many models feature an ability to cook sticky rice or [[porridge]] as an added value. Most can be used as [[food steamer|steamers]]. Some can be used as [[slow cooker]]s. Some other models can bake bread or in some cases have an added function to maintain temperatures suitable for fermentation of bread dough or yogurt. Multi-purpose devices with rice cooking capability are not necessarily called "rice cookers", but typically "multi-cookers".<ref>{{cite web |url=https://www.independent.co.uk/extras/indybest/house-garden/kitchen-appliances/best-multi-cookers-2016-currys-8-in-1-reviews-9052033.html |title=9 best multi-cookers |newspaper=The Independent |date=21 September 2018|author=Kate Hilpern|access-date= 10 February 2019}}</ref>

A rice cooker, or [[slow cooker]], can be used in conjunction with a temperature probe and an external thermostat to cook food at a stable low temperature ("[[sous-vide]]").<ref>{{cite web |url=https://food-hacks.wonderhowto.com/how-to/cook-food-perfectly-home-with-super-cheap-diy-sous-vide-machine-0148452/ |title=How to Cook Food Perfectly at Home with a Super Cheap DIY Sous Vide Machine|website=Food Hacks|date=5 September 2013|author=Gabrielle Taylor|access-date= 10 February 2019}}</ref>

==Other uses==
Steam rice cookers have been shown to be effective for decontamination of face masks.<ref>{{cite journal
| last =Daniel
 | title =It's not the heat, it's the humidity: Effectiveness of a rice cooker-steamer for decontamination of cloth and surgical face masks and N95 respirators
 | journal = American Journal of Infection Control
 | volume =48
 | issue =7
 | pages =
 | date =July 2020
| url = https://www.ajicjournal.org/article/S0196-6553(20)30238-8/fulltext
| access-date = 12 July 2023}}</ref>

==See also==
{{portal|Cooking}}
{{div col|colwidth=30em}}
* [[Rice polisher]]
* [[Slow cooker]]
* [[Remoska]], small portable oven
* [[Vacuum flask]]
* [[Hot water dispenser]]
* [[List of cooking appliances]]
* [[List of Japanese cooking utensils]]
{{div col end}}

==References==
{{reflist}}

==Further reading==
{{Commons|Rice cooker}}
{{Cookbook|Rice Cooker}}
*{{citation|title=Where There Are Asians, There Are Rice Cookers: How 'National' Went Global via Hong Kong|last=Nakano|first=Yoshiko|isbn=978-988-8028-08-5|publisher=Hong Kong University Press|year=2009}}

{{Japanese food and drink}}
{{Authority control}}

{{DEFAULTSORT:Rice Cooker}}
[[Category:Rice]]
[[Category:Chinese food preparation utensils]]
[[Category:Cooking appliances]]
[[Category:Cooking vessels]]
[[Category:Cookware and bakeware]]
[[Category:East Asian food preparation utensils]]
[[Category:Japanese food preparation utensils]]
[[Category:Japanese inventions]]
[[Category:Korean food preparation utensils]]