Does Microwave Kill Bacteria? Everything You Need To Know

Microwaves have been helping families with saving time in the kitchen for decades. They’re the easiest way to heat up your leftovers. They can even defrost food from the freezer so you can cook it faster. They are so convenient, but does microwave kill bacteria? As much as I love a simple meal, I don’t want to get sick from it.

There are so many dangers associated with food-borne bacteria. Food contaminated with bacteria is full of pathogens and other harmful viruses that could potentially make you very sick. If you’re not safe you could end up with an upset stomach, diarrhea, fever, and vomiting. 

Bacteria can be killed in the microwave. The heat that the microwave creates is what breaks up the particles. Kills any bacteria that is growing on your food. Microwave heat works by warming the food up from the outside first until the heat reaches the middle. This could cause irregular shaped food not to be heated all the way through in certain areas.

Does microwave kill bacteria thoroughly then? The heat from the microwave will kill most food-borne bacteria so you can eat your food safely without worrying about getting sick. Keep reading for more information on how to safely heat your food up in the microwave.

Do you know how to defrost meat in a microwave? Read it here.

How Long Does It Take A Microwave To Kill Bacteria?

In order to kill all the bacteria that could be growing on your food it is important to make sure you leave it in the microwave long enough to get properly heated all the way through.

So, how long does it take a microwave to kill bacteria? Well, that all depends on what you put in there and how big it is. Remember that a frozen solid food item will heat up differently than a liquid, such as soup. You could need anywhere from 60 seconds to 5 minutes in order to successfully kill all of the bacteria.

Make sure your microwave is on the highest power to kill those germs. Researchers found that microwaving a damp sponge for 2 minutes can kill 99% of the bacteria that was growing on it. That includes things as disgusting as fecal matter.

Does Microwaving Kill Bacteria In Water?

As mentioned above it’s not the microwave that kills the bacteria, but the heat from the microwave that does the job. So if you’re wondering does microwaving kill bacteria in water we’ll explain how it’s actually one of the better ways to get the job done.

You can kill bacteria in water as long as it’s heated to boiling point. All of the germs actually die off along the way to getting boiled. When you heat the water up in the microwave it’s in a confined space, so the heat is going directly to the water. That results in heating the water faster than boiling a pot on the stove. When you boil water on the stovetop the heat works by heating the bottom of the pot and waiting for it to heat up everything inside.

The only issue with using the microwave to kill bacteria in the water is that you have less control. The water is likely to splash out of your dish making a big mess if you don’t have a proper cover.

Can You Kill Salmonella In The Microwave?

Salmonella is a food-borne disease that is found in raw chicken, vegetables, and eggs, among other common foods. You need to be careful when preparing your food because salmonella infects over 1 million people every year. The scary thing is that it is often associated with foods that are normally a part of our regular diet.

Can you kill salmonella in the microwave too? Your microwave can produce enough heat to safely kill salmonella. You need to make sure that your food is heated thoroughly to 165 degrees fahrenheit (73.9 degrees celsius) to avoid this risk. Salmonella, like most bacteria, can survive in a temperature range of 5 degrees-47 degrees celsius. It’s prime temperature for multiplying is between 35-37 degrees.

To reduce the risk of salmonella or any other food-borne bacteria, make sure you always follow safe food handling practices. Alway get your leftover food to the refrigerator as soon as possible to reduce the risk of bacteria growth.

Does Microwave Kill Bacteria? Final Thoughts

It turns out that it isn’t your microwave itself killing the bacteria, rather the heat that it produces. When you heat food up in the microwave it is in a more confined space and the heat is directly hitting the item. This helps heat the food up quicker and can be a more eco-friendly way of killing the bacteria, compared to stovetop heat.

You may have issues with irregular shaped food items not being heated all the way through. To reduce the issues this may cause, try pausing the microwave and flipping or turning the food around a few times to get it heated thoroughly.

To be extra safe, keep a food thermometer handy so you can get the internal temperature and make sure you’ve reached the safe zone. Never store food in cold temperatures that are higher than 5 degrees celsius or in hot temperatures that are lower than 45 degrees celsius. We hope this helps you understand how the microwave can help kill bacteria on your food (and sponges). Remember to always follow your microwave’s instructions for safe food practices.

Read my article on how to microwave an oats to perfection.

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