Can Cardboard Go In The Microwave?

Microwaves are incredibly convenient utensils for heating food or drink. Most foods can easily be heated in a matter of minutes. So if you have leftovers, it’s super simple to reheat food.

However, knowing what materials are safe to microwave can be tough. This is because certain materials, such as metal, should never be heated in the microwave.

If you have been asking “can cardboard go in the microwave”, you’ve come to the right place! The answer is a little confusing, as some cardboard containers are microwave safe while others aren’t. Let’s explore why!

Can You Microwave Cardboard?

In some cases, cardboard is safe to microwave. In others, microwaving cardboard is not safe. This is because the cardboard can catch fire when heated in the microwave.

The reason for this is that cardboard can contain combustible chemicals, such as a waxy coating or other materials that may ignite. Moreover, cardboard containers can include metal elements that can be a safety hazard in the microwave.

Though not all cardboard containers will catch fire, the risk is too great. Cardboard can be microwaved for short periods, though if you heat it for too long this could be hazardous. Therefore, it is best to refrain from microwaving cardboard altogether.

If the instructions found on a microwave meal say that the cardboard container is safe to microwave, then you can use it without fear of it catching fire. If the product does not feature a microwave-safe label, you must not put it in the microwave.

Can You Microwave Cardboard Pizza Boxes?

If you have leftover pizza from the takeaway you ordered the night before, you might be wondering whether these boxes are generally safe to microwave.

After all, it’s a lot less hassle to reheat a pizza in its cardboard pizza box than to transfer it to a microwave-safe plate.

The good news is that most pizza boxes are safe to reheat in the microwave. Just make sure that the cardboard box has been specifically labeled as microwave safe.

Are Brown Paper Bags Safe To Microwave?

No, these brown paper bags are not microwave-safe. They do not withstand high temperatures, meaning that they are liable to catch fire. When they are heated, brown paper bags may emit toxic fumes. These toxic fumes can cause breathing difficulties. Not to mention, this method of reheating food has proven to be unsanitary.

On the whole, you must avoid using these paper bags in the microwave.

Are Paper Plates Safe To Microwave?

Most paper plates are appropriate for use in the microwave. On the other hand, paper plates may have a plastic coating.

This plastic material is not best-suited to microwaves, so you should avoid using these plates if you wish to reheat food. Remember to check the label to see if these plates are appropriate for use in microwaves.

Are Cardboard Takeout Boxes Suitable For Microwaves?

If you’ve ever had a takeaway, you’ve likely been served the food in plastic or cardboard takeout containers. To reheat the leftovers, you may wish to keep the food in the takeout box.

But the truth is that these takeout containers are designed to supply food, not reheat it. As a consequence, these cardboard takeout boxes may not survive the warm temperatures of the microwave.

Can Coffee Cups Be Used in the Microwave?

If you have ordered a cup of coffee from a local store, you may wish to reheat this brilliant beverage in your microwave. Unfortunately, coffee cups are not designed to be microwaved. The majority of these cups are made with plastic or wax coatings, which can start a fire when microwaved.

Can Cardboard Go In The Microwave?

Microwave Safety Tips

To ensure that you are safe when using a microwave, you must follow these easy and practical tips:

  • Always follow the manufacturer’s instructions. This includes the instructions in the manual for a specific microwave.
  • Also, follow the cooking instructions on the packaging of food. This will tell you not only how long you should reheat food, but also what parts of the packaging are microwave safe.
  • Never use a microwave with a faulty door. The door of a functional microwave oven will remain closed, as this can be a safety issue.
  • Refrain from using metal materials in the microwave. This includes aluminum foil.
  • Always use a microwave-safe container if you wish to reheat food or drink.

How To Microwave Cardboard Safely

Though we recommend refraining from putting cardboard in the microwave, this material can be used in the microwave so long as you are incredibly careful. If you are determined to microwave cardboard, here’s what you should do when heating cardboard:

Ensure that there are no metal parts in the cardboard. This can include metal handles, which are commonly found on cardboard containers. Staples may have been used to seal the cardboard, so be sure to remove them.

Check the labels to make sure that the cardboard container is safe. If the cardboard box is designed to heat food, there should be accompanying instructions. Furthermore, don’t use wet cardboard. The moisture content can lead to fires.

Fill an empty cardboard container with whatever food you want to be reheated. When microwaving food in a cardboard box, it is best to turn the microwave on for as little time as possible. Of course, you must obey food hygiene rules when heating this food. You may also wish to opt for a low-power setting.

Be careful when handling reheated food, as it can be very warm. You may wish to use an oven glove to protect your hands.

Never leave your food in the microwave unattended. This way, you can spot any smoke coming from the cardboard, which could result in a fire. If your microwave becomes smoky, turn it off immediately.

Once you have finished, remember to recycle the cardboard. Recycled cardboard can be beneficial for the environment as it can be transformed into another product.

Closing Remarks

Though microwave ovens are incredibly useful cooking tools, they can be somewhat dangerous. It’s important to educate yourself on how to properly use microwaves, including what materials are microwave safe.

Otherwise, the simple act of microwaving food or drink can become hazardous! 

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Kathryn Sewell

Hi! I'm Kate and I have been baking and cooking for as long as I can remember. I like to share the most interesting tips and recipes I try here on What Kate Baked for you to enjoy. If you have a favorite recipe you'd like to share send it over on social.

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