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Why did my soup explode in the microwave?

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Why does my soup “pop” violently in the microwave and then still come out lukewarm? Why does soup explode in the microwave? How do you keep soup from exploding in the microwave? How to microwave soup without exploding

Microwaves improve speed, efficiency and overall convenience. But cleaning up a huge mess after microwaving soup isn’t really helping out.

From thick to thin, soups have a tendency to make lots of noise and “pop” violently while inside the microwave, but still manage to come out being lukewarm. So what is going on inside the microwave and why is the food not hot?

Microwaves use electromagnetic radiation heat food. Water molecules are excited by the energetic flow, which causes them to move around violently resulting in intense friction that generates heat.

Microwave heat up food unevenly. If left unattended, you will experience burning hot areas directly next to cold or even frozen areas in the case of frozen food. Frequent stirring is recommended to promote even heating, along with a turntable inside the microwave is useful.

Why did the soup explode in the microwave?

Cleaning up food splatter inside the microwave is not the definition of a fun time. To understand why the soup exploded inside the microwave, we must start by understanding superheating.

Superheating liquids in the microwave is a phenomenon where extremely hot liquid are trapped underneath layers with cooler temperatures. Steam vapor builds up under pressure and is trapped below the surface tension, which can lead to a dangerous explosion of severely hot liquid.

Soup will explode in the microwave because the surface has trapped steam underneath. Therefore, it’s important to place foods in the center of the microwave so that the heat is more evenly distributed.

A wooden spoon, skewer or stirring stick should be left in the container while heating to break up the surface tension. The wood stick will help to breakup the surface tension, which may also prevent the superheating effect.

In addition, soups and thick liquids should be stirred frequently while heating. Open the door every 30 to 60 seconds to carefully inspect the soup and give it a quick stir.

Why does tomato soup explode in the microwave? Viscosity of the liquid has a direct correlation with fluids exploding in the microwave. Although tomato soup may not be as thick as a chowder, it is definitely thicker than water.

In general, boiling water in the microwave does not explode as often as heating up a thick soup like chowder. Follow adequate safety precautions to reduce the risk when heating up soup in the microwave.

Clear broth soup in a white soup bowl inside the microwave

How do you keep soup from exploding in the microwave?

It is convenient, simple and safe to microwave soup, but you may have to adhere to basic recommendations. Here are easy ways to keep soup from exploding in the microwave:

  1. Use a microwave-safe soup container. Glass or ceramic mugs and bowls work best, but you can use anything labeled “safe for use in microwave.” It’s not recommended to microwave soup in take out containers.
  2. Remove the cover. Never heat foods in the microwave with a completely sealed cover or airtight lid.
  3. Place container of soup in center of microwave. The focal point is the center of the microwave, so place food in the center to heat food quickly and more evenly.
  4. Insert a non-metallic object into the soup. A wooden skewer, popsicle stick, or chopstick will break tension on the surface, which helps avert superheating.
  5. Heat soup in 1-minute intervals. Carefully check the soup after every 1-minute duration and give it a good stir to promote even heating.
  6. Carefully tap the container of soup to check for superheating. Disrupt the surface tension inside the soup by tapping the side of the container with a stick or spoon. The soup may explode violently if the surface tension is broken.
  7. Cautiously remove the soup. Use hot mitts to avoid burns from the hot container or splashing soup.

Heating soup in the microwave is fast and efficient, however you must follow these precautions to prevent soup from exploding in the microwave. According to the USDA, recooking food is considered a potential food safety hazard and soups should be reheated to 165 °F.

Things to know before heating soup in the microwave

Soup can definitely explode in the microwave. Therefore, adequate measures need to be taken to prevent a dangerous soup explosion and unnecessary microwave cleaning associated with it.

Microwave heat up food unevenly, therefore it is best to heat up a small amount of soup at a time. Use a microwave safe soup bowl, heat uncovered in 1-minute intervals, and stir frequently to promote a balanced distribution of heat.

Thicker soups are much more likely to splatter than thinner liquids. Heat concentrates more easily in viscous liquids, which allows steam vapor to expand until it is large enough to explode and make a mess.

Foods should be centered inside the microwave because heat is more consistently dispersed. Remember that it is important to reheat foods to a minimum temperature of 165 °F.

Microwaving soup may not be the best option when compared to heating up soup on the stovetop. However, these safety precautions can prevent soup exploding in the microwave when done correctly.

Why did my soup explode in the microwave?