Can You Microwave A Thermos?

A thermos flask has been an awesome way of keeping your meals or drinks either warm or cool. However, if perchance the item in your thermos needs reheating, this makes you wonder, if it’s safe to microwave a thermos cup or flask.

As it’s a proven fact that placing metal into a microwave isn’t safe, you’re advised to do so. This begs the question if the same applies to thermos-made containers. 

Some experts advise against microwaving thermos-made containers, because it made need sparks, or cause damage to the microwave. However, with some necessary precautions, you can safely microwave a thermos container, but if you can’t, it’s best to choose a microwaveable container.

How to safely microwave a thermos container; it is best to open the lid of the flask or cup, set the microwave timer to 30 seconds under supervision, allow the microwave to cook, then open and check if it’s to your desired temperature. 

Heating a thermos in the microwave can be dicey, many choose to decide if it’s microwave-safe or not from personal experience. Nevertheless, this writer would discuss the best way to heat items inside a thermos container, and how to safely microwave a thermos. 

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The Safest Way To Heat A Thermos

The proper and safest way to heat a thermos container is by preheating it with boiling water, then adding your hot food or drink into the container, and it would be kept warm for about 5-14 hours. 

This is because some experts advise not to microwave a thermos, thus, offering this safe-secure system that can help heat a thermos, so you can store your food or beverage for hours.

To heat a thermos without a microwave; you simply start with boiling some water in a separate container on the stovetop or microwave. After boiling, pour the heated water into your empty thermos container until the container is full. 

Be careful when pouring in the hot water, close the lid of the thermos, and allow sit for about 5-10 minutes. After then, you can remove the lid, and pour out the water. Then, proceed to dry the insides of the thermos with a towel, we advise a big one, so you can wrap the thermos when cleaning, as it will be extremely hot. 

When dry, carefully add your hot food or beverage of choice into the preheated container and the thermos would help keep it warm. With this, your food or beverage can be kept warm on the go or at home for about 5-14 hours. (depending on the quality of the thermos).

Although it has been discussed above, how to heat a thermos without placing the container into the microwave. Some schools of thought, believe it is possible to microwave with a thermos. However there are some certain steps to follow, this would be discussed below. 

How To Safely Microwave A Thermos

Usually, this step should be taken if you’re not in the comfort of your home, or you have to heat the food or drink in your thermos as quickly as possible. Also; you must microwave a thermos under your supervision, and if you notice a spark or disagreeing noise, turn the microwave off immediately. 

Here’s a video on how to heat a thermos in the microwave.

As microwaves are made with metal, their heat radio cannot easily penetrate another metallic object or stainless steel-made containers. Therefore, start with opening the lid of the thermos (either thermos flask, plastic thermos, or stainless steel thermos), to allow heat waves to pass through and enter the food being microwaved with a thermos. 

Proceed to microwave the thermos, on medium heating for 30-40 seconds under your supervision. When the microwave goes off, wait for a few seconds before opening it and check if it’s heated to your desired temperature. If not, heat for additional 10-15 seconds. 

While heating watchful for sparks and ensures the thermos is completely dry, as any wetness could lead to the risk of sparks. It is worthy to also note that microwaved thermos food or beverage may come out not as evenly or thoroughly heated, but it would be safe for consumption. 

Final Thoughts 

Thermos-made containers are one of the best methods of keeping your food or beverage warm for a long period, this method keeps away bacteria and is safe to consume its contents both at home or on the go. 

However, there are two schools of thought, some experts believe in not taking the risk of microwaving a thermos, and instead preheating the container with boiling water and adding your food or beverage to keep warm. Or, following some safety techniques and you can achieve microwave a thermos.

Both thoughts have been discussed above, most people form their opinion after trying out both methods.

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