Rice is arguably one of the healthiest foods you can eat due to its low-fat content and higher carbohydrate content, but cooking rice the traditional way in a pot was a hassle, so it makes sense that people are flocking toward rice cookers.
Sometimes, you may cook way more rice than you need, so you may think that you can reheat it and use it again in another dish or save it in the rice cooker.
However, there is only a small window you can do this before you run the risk of food poisoning due to bacteria development.
So, how long can you leave rice in a rice cooker safely?
The short answer is that you have between 11 and 12 hours from when you first cooked it to eat it before you really should throw it out. However, since there are a few factors that come into play, it’s not a hard and fast rule.
We’re going to go over the factors that influence whether or not it’s safe to eat your rice after you’ve left it in the rice cooker for 11 to 12 hours. This way, you’ll get a good idea of whether or not you should risk it or toss it and make a fresh batch.
How Long Rice Lasts in a Rice Cooker
On the keep warm function, you can typically keep rice in your rice cooker for 11 to 12 hours without a problem. Bacteria can start to develop after this time, so you do have to be very careful.
Some rice cookers can preserve rice longer than others, especially when you get into the professional-grade ones like Cuckoo Corp that can keep for a few more hours without spoiling.
Can Rice Last Overnight in a Rice Cooker?
Technically, you can leave rice in a rice cooker overnight, but this isn’t something we recommend you do because leaving it overnight can allow the rice plenty of time to lose its taste and change colors, and this is a sign that bacteria are starting to form.
The best way to tell if your rice is still good is to try a very small amount, but you should toss it and start fresh if this isn’t a risk you want to take.
Understanding the Keep-Warm Function
Many rice cookers come with a keep-warm function on them, and this function works by keeping the temperature inside the bowl consistent at 140 or 150°F.
This temperature range is great for keeping rice ready for serving at a moment’s notice, and it both discourages bacteria growth while preventing the rice from burning and draining.
Some rice cookers have a keep-warm function that can last for 12 hours at a time, but you want to be careful with this length because of bacteria growth.
Bacteria in Rice
Partially or fully uncooked rice can contain dormant bacteria spores that can easily cause food poisoning with diarrhea or vomiting if you ingest them.
The bacteria live in the soil, and you can find these spores on beans, potatoes, and peas, as well as transferred from raw food.
Unfortunately, it’s not possible to know if your rice contains Bacillus Cereus by smelling, looking, or tasting it, so you want to cook your rice thoroughly and serve it right away to prevent any accidental food poisoning.
The keep-warm function will continue to heat the bottom part of your cooker’s bowl, and this will cause the water to slowly evaporate to dry out your rice. Once the water vanishes completely, bacterial spores can break open and start multiplying to spoil the rice.
Can Reheat the Rice Kill the Bacteria?
Unfortunately, reheating your rice won’t kill the active bacteria spores if it has already started to develop, and there is no way you can tell if your rice is safe to eat or not.
However, research shows that storing and reheating your rice the correct way is very critical when it comes to preventing developing a case of food poisoning.
Consequences of Eating Spoiled Rice
Eating spoiled rice will give you the same standard symptoms of food poisoning, including diarrhea, vomiting, and a stomachache. The symptoms usually manifest 30 minutes to six hours after you eat the spoiled rice.
However, if you end up eating Bacillus Cereus spores, it can take up to 16 hours for them to germinate in your stomach and cause diarrhea after you first eat the rice.
How to Safely Preserve Leftover Rice
The best and safest way to preserve your rice once you cook it is to switch your rice cooker off after five hours, take the rice out, put it in a container with a sealable lid, and put it in your refrigerator.
To keep the rice the correct texture and to preserve the taste when you reheat it, use a steamer over the rice cooker to keep it as fresh and tasty as when you first cooked it.
How Long Does Rice Need to Cook in the Rice Cooker
Usually, your rice will be done around 20 minutes after you first put it in, but the total cooking time will depend on the power mode, type of rice, and the amount you want to cook.
The device will switch to keep-warm mode once it finishes cooking until you reach over and manually turn it off, and this is when your rice is safe to eat, even if the bacteria spores are alive.
The more time passes, the higher your chances are of the spores breaking open and causing your rice to spoil.
However, if you take the rice out of the rice cooker straight away and store it at room temperature, you shouldn’t wait for more than a few hours to eat it.
Once a few hours go by, the rice can get soft, yellow, or crumbly, and these are all signs that it went bad. So, you can safely leave it out at room temperature for a maximum of two hours before it’s not safe to eat anymore.
Remember, you can store it for up to 12 hours on the keep-warm function in your rice cooker, but the temperature has to be higher than 140° Fahrenheit for it to be effective.
If the rice cooker can’t maintain this temperature or slightly higher, your heating time drops from 12 hours down to 8 before you have to toss it out to avoid food poisoning.
Safe Storage Options for Different Types of Rice
There are currently over 400 rice types available, and each rice type has a different shelf life when you store them uncooked.
Jasmine rice, wild rice, white rice, and basmati have an indefinite life when you store them uncooked in your freezer, refrigerator, or cabinet.
Brown rice has a shelf life of six months in the cabinet or up to a full year if you store it in the refrigerator.
Rice types also require different cooking times in your rice cooker, but the 11 to 12 hours of safe storage type rings true for all rice types.
The temperature has to be at or above 140° Fahrenheit at a minimum to keep it safe to consume for these hours. When cooked, don’t store your rice for more than a month in the freezer and six days in the refrigerator.
You can safely keep rice in your rice cooker for 11 to 12 hours at a maximum with minimal temperature ranges before you should toss it out.
Higher-quality cookers have slightly longer times, but you should always toss the rice and make new if you have questions about whether or not it is spoiled to prevent food poisoning.