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How to Reheat Rice Without Getting Food Poisoning

Reheated rice is the leading cause of Bacillus cereus food poisoning. Here is how to store and reheat rice safely every time.

By Mia Nakamura •

The Hidden Danger in Leftover Rice

Rice is one of the most common causes of food poisoning, and most people have no idea. The culprit is Bacillus cereus, a spore-forming bacterium that is naturally present in uncooked rice.

Here is the problem: B. cereus spores survive the cooking process. They are heat-resistant. When the cooked rice sits at room temperature, the spores germinate into active bacteria that produce a toxin. This toxin is also heat-resistant, meaning reheating the rice does not destroy it.

For more on this topic, see our guide on How to Clean a Scorched Rice Cooker Pot Without Ruining It.

The Safe Window

Cooked rice must be refrigerated within 1 hour of cooking (or within 1 hour of removing it from the keep-warm function). The longer rice sits at room temperature, the more toxin is produced.

For more on this topic, see our guide on Rice and Food Safety: The Bacillus Cereus Danger You Need to Know.

How to Store Cooked Rice

  1. Spread the hot rice in a thin layer on a baking sheet or wide, shallow container. This cools it rapidly.
  2. Once it stops steaming (within 20-30 minutes), transfer to an airtight container.
  3. Refrigerate immediately. Stored rice is safe to eat for 3-4 days.
  4. For longer storage, freeze rice in portion-sized bags. Frozen rice keeps for up to 6 months.

How to Reheat

Microwave (Best Method)

  1. Place rice in a microwave-safe bowl.
  2. Add 1-2 tablespoons of water per cup of rice.
  3. Cover with a damp paper towel or microwave-safe lid.
  4. Heat on high for 1-2 minutes, stirring halfway through.
  5. The steam from the added water rehydrates the dried grains.

Stovetop

  1. Add rice to a saucepan with a splash of water.
  2. Cover and heat over medium-low, stirring occasionally, until hot throughout.

Rice Cooker

Some cookers have a “Reheat” function. If not, place the cold rice in the inner pot with a tablespoon of water, close the lid, and press Cook for 5-10 minutes.

The Rule

When in doubt, throw it out. If rice has been sitting at room temperature for more than 2 hours, discard it. The $0.10 worth of rice is not worth the 24 hours of violent vomiting and diarrhea that B. cereus causes.