Rice cooker

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 rice cookers may have many 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 pressure cookers suihanki (炊飯器^?).

The cooking bowl is filled with rice and water. During cooking, the rice/water mixture is heated at full power. The water reaches a temperature of 100 °C (212 °F); it cannot get hotter than its boiling point (all the energy goes into vapourizing the water). At the end of cooking there will be no free water left; most will have been absorbed by the rice, and some boiled off. As heating continues, the temperature can now rise above boiling point; this makes the thermostat trip. Some cookers switch to low-power "warming" mode, keeping the rice at a safe temperature of approximately 65 °C (150 °F); simpler models switch off.

This means that if more water is added, the rice will cook for longer.

Cooking rice has traditionally required constant attention to ensure the rice was cooked properly, and not burnt. Electric rice cookers automate the process by mechanically or electronically controlling heat and timing, thus freeing up a heating element on the cooking range that had to be otherwise occupied for rice cooking. Although the rice cooker does not necessarily speed up the cooking process, with an electric rice cooker the cook's involvement in cooking rice is reduced to simply measuring the rice, preparing the rice properly and using the correct amount of water. Once the rice cooker is set to cook, the rice will be cooked with no further attention.

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Wikipedia