Why Your Rice Cooker Is Boiling Over? & How To Stop It

A rice cooker should not boil over if everything is alright, but there are at least five instances when you may have a bubbly, foamy, and starchy mess on your countertop. Thus, you need to know precisely why your rice cooker is boiling over for you to use a suitable remedy to stop it. 

Your rice cooker can boil over if it has excessive water, rice, or both. Also, several rice varieties have a high starch content, which creates bubbles that appear foamy and feel gummy. To stop it, you’ll need to check your rice and water measurements and proper instructions for the rice type.

Every rice cooker has a maximum capacity and is engineered to maintain a steady boiling temperature of 212°F (100°C). Follow the instructions in the manual to prevent a rice cooker from boiling over, and use the remedies in this guide to avoid all inadvertent problems. 

5 Reasons Why Your Rice Cooker Is Boiling Over

Generally, people classify rice as long-grain, medium-grain, and short-grain, irrespective of the variety, degree of milling, color, processing, and any special quality, such as aroma and flavor. 

In time, everyone realizes that it is impractical to cook different rice varieties in an identical way. 

The world has more than 120,000 rice varieties. Whether you are a home cook or an aspiring chef, you will discover that every distinct variety of rice needs some modification in how you prepare it, the water quantity you must use, and the method of boiling, cooking, and serving. 

The following five reasons are the most common causal factors for contemporary rice cookers boiling over. You’ll need to read these reasons while considering your rice cooker features, the rice variety you have, and the quantities you cook, including the proportion of water.  

1. You Have More Raw Rice Than the Maximum Capacity

All rice cookers have a maximum and a minimum capacity. Most rice brands include their standard cups in the box, so the rice quantity you cook should always be within this range. 

An inadvertent error could be missing out on the difference between raw and cooked rice. Take the example of Aroma Housewares Digital Cool-Touch Rice Cooker, a bestselling product with excellent reviews from customers on Amazon.com. 

This Aroma rice cooker clearly states that its maximum capacity is 8 cups of cooked rice. Thus, you can cook a maximum of 4 cups of raw rice. A typical expectation is that 1 cup of raw rice will be 2 cups of cooked rice after absorbing water during the entire boiling or cooking process. 

However, some rice varieties expand more than twice their raw size by absorbing more water. 

Thus, you cannot cook 4 cups of raw rice for such varieties in this Aroma model. If a rice variety expands up to three times its raw size through boiling, the maximum you can safely cook in this Aroma model is 2½ cups. Any more, and you have the risk of the rice cooker boiling over. 

The maximum capacity and its definition or the details, such as the cup size of raw and cooked rice, are fundamental aspects of such appliances. You must adhere to these specifications even when you have more people than you expect at a given time and thus need to cook more rice. 

2. You Have Too Much Water In the Rice Cooker

Like excess raw rice, more water than necessary will cause your rice cooker to boil over. 

All rice cookers are engineered to hold a maximum quantity of water and rice. However, a widespread issue is the proportion of water used for different rice varieties, also depending on recipes. 

If you are only boiling some raw rice, the water may be in equal proportion, so 1:1. Many rice varieties require more than 1:1 water, while some recipes may even need rice and water in a 1:2 proportion. Hence, there is a high chance for such proportions to cause rice cookers to boil over. 

Your rice cooker may have markings inside the pot, as well as the measuring cup. Use the markings for real-time guidance, and exercise care to gradually change the proportions when you must do so for specific varieties of rice. A 1:2 rice & water ratio is not the industry standard. 

Another probable issue is the difference between rice measuring cups and standard cups in most American kitchens. A rice cup is generally 6 oz (180 ml), whereas regular cups are 8 oz (240 ml). 

Thus, a 1:1 rice and water ratio for these two cups is effectively 1:1.25 in oz or ml.  

When you opt for a 1:1.25, 1:1.5, or 1:2 using these two different cup sizes, there is a significant net increase in the quantity of water inside your rice cooker. Thus, boiling the maximum quantity of raw rice with so much excess water will almost certainly compel most cookers to boil over. 

3. Total Ingredients Exceed the Maximum Capacity

A rice cooker can boil over due to excess raw rice or water. 

Most rice cookers will definitely boil over if both rice and water are in excess. This compounding problem may be inadvertent for a few people or a calculated risk if someone tries to maximize one round of cooking rice. 

Also, a rice variety that needs more water in proportion to its raw size will worsen the net or compounding effect. A rice cooker may boil over if you use a rice cup and a regular cup of varying sizes while using a greater water proportion. 

The real-world kitchen or cooking experience rarely goes as planned. People have different approaches to preparing raw rice. Also, rice cookers don’t have identical features or settings for white, brown, or other rice varieties, nor the temperatures they sustain during cooking. 

4. You Are Cooking a Rice Variety With a High Starch Content

The raw rice quantity and water proportion are two relatively easy problems to detect and solve. 

A complex issue is the starch content in your preferred rice variety. There is no way one can generalize this without knowing the specific variety of rice and the raw quantities you cook. 

Any rice variety with excess starch will create foamy bubbles as the water boils, so these frothy bubbles rise in a rice cooker. Gradually, more bubbles populate the upper rim of the rice cooker as the appliance continues to boil the water and cook the rice. 

Eventually, there are too many foamy or starchy bubbles bursting under the lid for the rice cooker to contain them inside. 

As a result, you find an enormous foamy mess on and around your rice cooker, probably also on the floor. The situation may be worse if you are not watching the pot because the excess starchy water can dry up on your countertop and thus become a tedious chore for you to clean. 

A traditional practice in some Asian cultures is soaking and rinsing the raw rice before cooking it. You may soak starch-rich raw rice for a few minutes. The water will turn hazy, which is a telltale sign of abundant starch in the grains. 

Ideally, rinse this soaked raw rice once or twice. 

Also, soaking and rinsing with clean water gets rid of dust and other materials from the milling and processing phases. A few rice varieties need two to three rounds of extensive rinsing. You will see that the water turns less hazy after each rinse. Rinse starch-rich raw rice until some clean water does not turn hazy at all and thus remains clear, which will keep it from boiling over. 

Furthermore, soaked and rinsed raw rice cooks faster. 

Of course, all the other best practices regarding size or quantity are still relevant. Besides, you must always choose the appropriate settings on your rice cooker, be it white or brown, the optional timer, and other special features. 

5. Incorrect Rice Cooker Settings and Appliance Defects

Rice cookers have relatively simple settings, such as white or brown rice, timer, keep warm, and others. Check if you are inadvertently choosing the wrong settings, albeit that may not be the actual cause for your rice cooker boiling over. 

Also, don’t rule out any defects in the appliance. 

A rice cooker may have a faulty thermal fuse. Steam or vapor may leak if the valve or gasket is defective. Also, an improperly sealed lid will allow steam or vapor to leak, and your rice cooker may boil over for no fault of yours, such as excess quantity or abundant starch in the raw grains. 

Verify if you are following the instructions in the owner’s manual and take the remedial actions shared in this guide. If you are not erring in any way, consciously or inadvertently, the real culprit could be the rice cooker, and you must contact the manufacturer or consult with a technician. 

For safety, do not use a rice cooker if you suspect it has a flaw, be it the thermal fuse or any material defects. Use the warranty if it is still valid. A rice cooker may underperform before any components go kaput. 

However, there may not be evident symptoms before it stops working. 

How To Stop Your Rice Cooker From Boiling Over

Here are a few solutions to stop your rice cooker from boiling over:

  • Don’t exceed the maximum raw rice capacity of the cooker.
  • Always use the rice cup provided by the manufacturer. 
  • Use less water but in proportion to the raw rice quantity.
  • Use the rice cup to measure water or adjust accordingly. 
  • Soak and rinse starch-rich rice before cooking it.
  • Choose the appropriate settings on the rice cooker.
  • Test the minimum and maximum capacities of the rice cooker.
  • Get a different rice variety to verify if the cooker is the problem.
  • Try a few tricks like a wooden skewer, spoon, or spatula.
  • You may add some oil, butter, or salt to the raw rice and water.

Watch this video to use bamboo skewers to stop your rice cooker from boiling over:

A wooden spoon or spatula may work, too. Although the following video is not of a rice cooker, it shows how effective a wooden spoon or spatula can be to hold off the water from boiling over to a certain extent. 

This trick may work better if a pot or pan is not open like the one in the video:

Adding a bit of oil or butter can create a sort of coating on the rice grains, effectively creating a barrier. Also, butter or oil can break those starchy bubbles so that they don’t keep rising and frothing under the lid or at the rim of the pot of your rice cooker. 

Besides, butter, oil, and other similar options may prevent the rice grains from getting too sticky while adding a bit of flavor. 

Salt has the ability to slightly increase the boiling point of water, thus enhancing the cooking time and temperature of rice or other foods. Therefore, adding some salt may prevent a rice cooker from boiling over. 

However, no theory states that salt can break starchy bubbles. 

All popular rice varieties have substantial starch in the raw grains. Soaking the raw rice for a few minutes and rinsing it up to three times should prevent your rice cooker from boiling over. Otherwise, you have to try one of the other remedies in this guide or cook less than the maximum capacity.