If you know how to boil water, you can cook rice. That's the theory, at least. You still have to watch over it, adjusting the heat and turning it off in time to make sure the pot doesn't boil over or burn.
An automatic rice cooker makes the whole job worry-free. If you can measure, you can make perfect rice -- every time. This is a boon even for good cooks, who after turning on the cooker are free to focus on the parts of the meal where no machine could take over.
At the push of a button or flip of a switch, the rice cooker will monitor itself, noting its temperature and, in some high-tech cases, use fuzzy logic to adjust its own settings.
Many of today's rice cookers are like microcomputers, with smart heating systems, preset options that guarantee hot rice at a certain time, steaming trays that make it possible to cook an entire meal in one appliance and settings for different types of grains, including brown rice.
Most also have an automatic warming feature, which is a nice bonus; even with the lowest of flames, you'd be hard-pressed to keep rice warm on the stove without getting a thick crust at the bottom.
Considering the wide price range in rice cookers, how often you eat rice is a good gauge of how much you should spend on a rice cooker.
We tested several models, from a $30 Oster to a $260 Zojirushi. Each comes with its own measuring cup (slightly smaller than a standard cup), which should be used for the best results. That's because it often corresponds with the water lines marked in the pot. You put two cups of dry rice into the pot, for example, then pour in enough water to the "2" line. The cooking pots are removable and nonstick, so cleanup is a cinch.
At its simplest, a rice cooker works via a thermostat. Inside the center of the heating plate is a small thermal sensing device on a spring. When rice and water are placed in the cooking pot, which goes into the rice cooker, the weight of the pot depresses the thermal sensor.
Switch on the rice cooker and an electric coil warms up the heating plate and brings the water to a boil. Once the rice has absorbed all the water, the temperature will begin to rise past 212 degrees (the boiling point of water). When the thermal sensor senses this, the system turns off the heat and switches to the "keep warm" cycle.
