Electric rice cookers are equipped with two main types of heating elements: electric heating tubes and PTC (Positive Temperature Coefficient) materials. The electric heating tube provides excellent insulation, corrosion resistance, thermal conductivity, and mechanical strength, ensuring a long lifespan and high efficiency. On the other hand, the PTC heating plate offers self-regulating temperature control due to its positive temperature coefficient property, making it more energy-efficient and safe without producing an open flame.
Rice cookers are known for their high safety standards and rapid heat-up time, which makes them less sensitive to power fluctuations. This reliability is especially important in areas where electricity supply may not be stable.
The temperature control systems used in rice cookers include bimetallic and magnetic material-based systems. While both serve the purpose, the magnetic material system is generally considered more accurate and safer. Rice cookers can also be categorized based on their design: some are combined type, while others are monolithic. Additionally, they are classified by pressure levels—low pressure (0.04 MPa), medium pressure (0.1 MPa), and high pressure (0.15–0.2 MPa)—which affects how food is cooked. The cooking method can also vary, either through direct or indirect heating.
Since the 1950s, rice cookers have gained widespread popularity, particularly in Asian countries. In 1986, the United States produced 5.9 million units, while Japan reached 6.902 million. By 1987, China had already manufactured over 10.263 million rice cookers. In the mid-1980s, electronic rice cookers with microprocessors started to appear on the market. These advanced models allowed precise control over cooking parameters such as temperature, time, and heating mode, leading to better cooking performance and more consistent results.
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