How Does A Rice Cooker Work?

I grew up with my Chinese grandma and that meant eating rice with almost every meal. She used a simple, one-button rice cooker, and measured her rice and water using nothing but her index finger.

The rice was always perfect and I distinctly remember the audible click the rice cooker made. A signal that the rice was ready and it would soon be time to eat.

Since then, I’ve used dozens of rice cookers, in professional kitchens and at home. And every time, I would press a button and walk away, never thinking twice about it.

But not today. After far too long, I’ve taken the time to get to know the little machine that has gotten me through countless meals at home and busy services at work. And I can finally answer the question; how does a rice cooker work?

Rice Cooking Basics

You can use a pot, an ancient rice cooker from your grandparents, or a high-tech Japanese model. No matter what you’re using, taking rice from dry grain to fluffy, chewy, and delicious is a fairly straightforward task.

The steps are simple. Dry rice grains are covered with water and a lid, then heat is applied. As the water gets hot it will force its way into the rice grains so that it becomes soft and edible.

One of the keys to making the best rice is using the right ratio of water to rice. The goal is for the rice to finish cooking at the same time as all of the water is absorbed.

Too much water and the rice will simply continue to absorb, leading to mushy rice. Too little and your rice will still have a raw, crunchy center and there’s a good chance the bottom will burn.

Following the ratio on each rice package is usually a pretty safe bet. And most rice cookers will include measurements that will do most of the work for you.

Not All Rice Cookers Are Created Equal

There’s a seemingly endless number of rice cookers on the market, with models available for under $20 and others that will cost you over $500.

So, what’s the big difference and why would you buy one rice cooker that costs 25 times as much as another?

There are a couple of reasons that make expensive rice cookers expensive.

Heating Element

Less expensive models rely on radiant heat to cook rice. Think of this like the heating coil you’d find on a standard electric stove. The coil gets hot and that radiates heat to boil the water and cook the rice.

Very high-end rice cookers use induction technology to heat and cook rice. Induction heating uses an electromagnetic field that creates electric currents within the cooking pot to produce heat. I won’t bore you with the science now, but if you’re interested you can read more here.

All you really need to know is that induction rice cookers use very little energy and cook very evenly at very precise temperatures. Oh, and they can be very expensive.

Settings And Features

The least expensive rice cookers generally feature one single button or lever to make the magic happen. Place your rice and water in the pot, press the button, and you’re off to the races.

Now, this isn’t necessarily a bad thing. These models have very few moving parts and no complicated sensors or computers. So, inexpensive rice cookers can sometimes be the most reliable and longest-lasting option.

As rice cookers become more expensive, you’ll often see more features, settings, and cooking modes. These options can often be used for more than just rice, and will usually have settings for different rice types as well.

Many of these models will also have delayed start timers so you can set your cooker to start at a specific time regardless of whether you are home or not. And, some have impressive “keep warm” settings that will keep your rice ready to eat for up to 24 hours.

Do you need a rice cooker that costs several hundred dollars? Probably not. 

If you cook rice the same way you cook pasta (don’t do that) you’ll be plenty impressed with the results of a $20 model. But, if you want the best, most consistently cooked rice every time, you might consider splurging. 

How Does A Rice Cooker Know When Rice Is Done?

One of the most remarkable things about automatic rice cookers is how they seem to know exactly when your rice is done. You could be cooking any type of rice and the machine somehow knows when the grains are perfectly cooked (hopefully).

Even the most inexpensive models will contain some form of temperature sensor. And this sensor is set to shut the machine off or turn to a warming function as soon as the temperature goes over the 212 F mark.

Since water boils at 212 F, as long as there is water in the pot, it should never get hotter than that. But, as soon as all of the water has been absorbed or evaporated, the temperature will begin to climb higher. And that rise in temperature will trigger the machine to shut off.

If your rice cooker shuts off and you find your rice is over or undercooked, chances are good that the wrong amount of water was used rather than the rice cooker being broken.

Rice Cooker vs. Regular Pot

Why use an expensive or even an inexpensive rice cooker when you can use any old pot that you already have? Well, I hate to admit it, but this is one machine that can really outcook just about any home cook or professional chef.

I often turn to a plain old stainless steel pot when I cook rice at home. But that’s largely because I’m stubborn, I like a cooking challenge, and I don’t want the machines to win.

However, rice cookers are generally much more reliable and produce more consistent and overall better results than a pot on the stove. With a regular pot, your stove temperature, how and when you adjust it, and I swear even the star’s alignment plays a role in rice being slightly under or overcooked.

So if you cook rice often, it’s probably best to swallow your pride and let the rice cooker do its job (talking to myself here).

Final Thoughts

The process of cooking rice is a simple one, and the rice cooker has perfected it. As long as you use the right amount of rice and water, you can have perfect rice every time. And remember, if you find your rice to be dry or mushy, try adjusting the amount of water you use before concluding that your machine is broken.

But, if you are in need of an upgrade or even your very first machine, take a look at the 3 best Japanese rice cookers that will take your meals to the next level.

Frequently Asked Questions