Can You Microwave Cardboard

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Love grabbing food from your favorite spots?

Do you even want to take out food? Do you live near the nearest quick service restaurant?

If so, are you aware of the dangers of microwaving cardboard?

Or you are just curious and want to know if it is safe to microwave cardboard.

Then this article is definitely for you.

Cardboards are made from a variety of materials.

These include paper, wood fibers, sulfate of paper (sodium sulfite), kraft fiber, cellophane, and nylon.

The standard cardboard that we get in the grocery stores is fibrous kraft paper which can be recycled repeatedly.

On the other hand, fiberboard is made from wood fibers and has no recyclable value since it cannot be recycled.

The standard type of cardboard is made from paper, a product that cannot be recycled, and up to 50% of it will end up in the landfill.

Therefore, microwaving food wrapped in cardboard is potentially hazardous.

Here’s why:

Cardboard does not have a heat-reflective surface and therefore has no thermal protection.

So if the cardboard gets too close to the heating source (microwave oven cavity), it will get very hot.

Even if a few pieces of paper do not get burned entirely, there will still be some discoloration, affecting the flavor of the food.

Also, since the cardboard is not moisture resistant, moisture absorbed from packaging will make cardboard absorb water and swell.

This will result in making the product brittle and easy to break.

Is it safe to microwave cardboard?

Since the cardboard is not heat-resistant and cannot be recycled, it is definitely not safe to microwave.

This is a complete waste of energy.

The only possible use of microwave ovens is heating food, reheating food, and cooking butter (which is not a good idea).

Do not microwave foods wrapped in cardboard for any reason whatsoever.

If you want to warm up your leftover food from the previous night, put the cardboard box in a microwave-friendly container on top of the cooking dish.

Alternatively, use a warming drawer or broiler instead.

Always dispose of cardboard properly.

It can be placed in your normal garbage, but it is a waste to use the microwave oven because it just creates more trash.

Never microwave food wrapped in cardboard into anything. Instead, use the microwave-friendly container or warming drawer to warm up frozen fruit, cereal, and leftovers from the previous night.

Make sure the cardboard you use is the type that can be recycled.

Avoid using the fiberboard type of cardboard.

Although it is fine for your pizza box to get microwaved, you should never microwave other types of food wrapped in cardboard, like soups, casseroles, etc.

When you read on the back that a package of food is microwave safe, you can be sure to microwave it because the manufacturer tested it with the oven and determined that this type of packaging keeps contents hot until it is heated to the specific temperature.

However, microwaves are dangerous, so you should always use caution when using this appliance.

Will cardboard light on fire in the microwave?

Since cardboard boxes cannot be recycled, it is not safe to use them as containers for food.

Although it does not sound like a problem for microwave ovens, the material will catch fire because of the intense heat.

The fire will have no outlet and will make the temperature in the microwave rise to a high setting.

If this happens, the microwave will overheat, which can cause a fire or explode.

If you are microwaving food with cardboard and are worried about a fire, using a microwave-friendly container is unnecessary.

Wrap your food in aluminum foil and put it inside your microwave.

To ensure there is no fire hazard, you should never exceed the maximum temperature for cooking according to the microwave’s instructions.

Also, some people mistakenly think that folding the edges of a cardboard box will prevent it from burning in the microwave.

However, this is not true; it is still flammable and can ignite even if you fold the edges a little.

Furthermore, if you pack food in a cardboard box to heat it, damaging the cardboard box will also damage the food inside.

In addition, cardboard boxes are paper-based so that they can become a fire hazard should the cardboard catch fire.

Ensure that you do not leave cardboard boxes lying around (especially if they are old).

Can you microwave cardboard safely?

As mentioned before, if you want to microwave food wrapped in cardboard, you should use a microwave-safe container with a lid on top of the dish.

You can also use a warming drawer.

So yes, you can microwave cardboard safely.

However, when it comes to making sandwiches, you should not use a cardboard container.

Instead, try wrapping your food neatly with aluminum foil.

Or else you can always go without cheese and bread and instead fill the sandwich up with vegetables like lettuce or sliced radishes and tomatoes to make salads instead of sandwiches.

Another way is to wrap your sandwich tightly in aluminum foil after putting it inside the microwave dish.

The same applies to heating leftovers from dinner the night before.

Although many people like tossing their leftover food into a box until they are reheated in the microwave, some people would prefer using a container (like an insulated one) or an electric warmer instead for storage purposes so that their leftover food does not spoil.

Cardboard packaging paper and cardboard boxes provide no insulation.

Even if they are not microwaved, they can still become a fire hazard.

How long can you microwave cardboard?

There is no specific time limit for microwaving cardboard.

However, you should use common sense when deciding when it is safe to microwave cardboard in the microwave.

If you are not sure, you can heat small parts at a time.

Or, if a piece of your cardboard packaging paper gets too hot to touch, it is best to stop microwaving it immediately.

You may also want to wrap your cardboard packaging paper in aluminum foil or put it inside a plastic bag before microwaving.

You can also cut the cardboard packaging paper into smaller pieces to ensure that they do not get too hot before microwaving them.

In addition, some people also make their cardboard containers by cutting two triangles out of the middle of a box.

Or else they could use an empty water bottle (preferable one with a screw cap) as a container for microwave reheating purposes instead.

It is advisable for anyone who decides to utilize this method by showing caution when handling the bottle with hot water inside.

Some tips To Microwave Cardboard

Now let us see what can be done to safely microwave cardboard packaging paper or containers without getting a fire hazard or burning the food inside.

1. Do not put too much food in your cardboard container at one time.

2. Use a smaller microwaveable container if you will be heating individual pieces of food. Otherwise, your food may get too hot faster.

3. Look if the cardboard is soaked with water by poking it with a knife or fork. If you have a plastic container, use a small amount of water to ensure that it does not get too hot. Otherwise, you may get a fire hazard.

4. Microwave the cardboard packaging paper or container at a lower temperature than usual. Normally, it is recommended that microwaves are used at a temperature of 450 °F or above.

5. If you will be reheating food in your cardboard container, put water in it first, so the water does not get too hot. Usually, paper and plastic containers should have enough room for water so that the water is not too hot for microwaves to work properly.

6. Place the cardboard packaging paper or container on a microwave-safe plate to catch any spillage or drips from the food inside during reheating.

7. After reheating, make sure that your cardboard container is cool enough before opening it up to check if there are any burning smells from the food inside it.

Final Words on Microwaving Cardboard

To sum up, cardboard containers and boxes are widely used in our daily life.

At times, it is very important to use it for preserving the safe and good quality of food or other items, but at the same time, it is also prone to heat up to a very high temperature and release gases or liquids.

Since the process of microwaving cardboard packaging paper is not always safe and reliable, it needs great caution and care when using it.

Since the form of a cardboard container is flat, it is very easy to stack them one on top of another.

This makes it possible for a bigger stack of paper packaging containers to store more food in more space.

However, if the stacked boxes or containers are not properly sealed, they will allow air to enter.

While this may not affect their temperature and contents when heated in microwave ovens or when warmed in an oven, the open containers will support too much moisture, which will cause them to burst into flames once microwaved.

So, I hope that this article may be useful to you in using cardboard containers and boxes safely.

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