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You wake up the next day, happy to find out that the pizza you ordered last night and placed its leftover in the fridge for the next day, is still intact and nobody ate it. The thing is who doesn’t love leftover pizza? In fact, some connoisseurs such as myself love it more than a fresh, straight-out-oven one.
The cheese becomes settled and the flavor is amazingly accentuated and…. Well. Anyways, it’s an entirely different debate. The point to ponder upon is how many times have we thought about jamming that cardboard box containing the leftover pizza, straight into the oven without realizing if it’s safe or not? If you haven’t given it a thought yet, then maybe it’s time that you should consider that can you put cardboard in the microwave oven or not?
You can place a cardboard box with food in it (e.g. pizza) in the microwave, but not empty cardboard. Also, you need to take some other precautionary measures as well due to different contents in different cardboards.
I have noticed that just because cardboard or paper can be used as a shortcut to start fires, one might think that it is not safe to reheat a portion of food that came packaged in a cardboard box while it is still in it, but cheers; after all it is safe.
The actual science behind heating up of food in a microwave oven is that when it is heated, the water molecules that are in that drink or food, commence moving at a high frequency. Through this technique, the entire drink or food gets heated up.
The reason that there is no danger of starting a fire while heating a cardboard in a microwave oven is that it doesn’t contain much amount of moisture and it is drier. Thus, it will take much more heat to start a fire with cardboard while heating it in a microwave oven.
Let’s just say that our cardboard is not completely dry and has some amounts of moisture due to the food that is contained in it (such sauces, ketchup, mayonnaise, etc), even then it is very unlikely to reach such temperatures that will cause the cardboard to catch fire.
Obviously, it is assuming that you are using your oven in a completely normal manner and you do not have psychopathic tendencies (just a bad joke).
But let’s just not paint all the cardboard-heating cases with a single brush of positivity. There might be some points to consider before delving into the adventure of heating your food right from the cardboard box it came in.
Sometimes It Is Not Safe to Microwave Cardboard
Yes, you read it right. After all the appeasements that we provided you with, above, still we have got to give you some warnings.
There is no doubt that although generally, it is safe to microwave cardboard, but one still needs to be aware of some situations where it is simply unwise to do so.
In the light of ‘first things first’, the foremost task to do is to check the labeling on the cardboard box that you are going to put in the microwave oven. We will advise that if there is no explicit microwave-safe pass inscribed on the box then it is wise not to do it.
Most companies that manufacture cardboard boxes inscribe on it ‘microwave-safe’ if their products are microwave-safe.
The next tip is to always be sure enough to check the labeling on the cardboard box that you are heating as most of them come with labeling that explicitly labels the stuff that has used in their manufacturing.
The reason to consider this is that most cardboard boxes are made of recycled material. Now this might light up the inner ‘eco-friendly’ instincts in you, but this does put an additional task on your side because recycle stuff can virtually contain anything, from plastic to wood, from paper to metal.
Now if the list of contents of manufacturing material contains metal, then it is a dangerous thing because the metal is not safe for microwaving. It can trigger not only fires but also severe damage to your microwave machine.
An additional thing that I want to specify here (that is not related to cardboards) is that since I have mentioned metals, so also make sure to refrain from heating up those metal containers in which they pack your leftover food in Chinese restaurants.
Moreover, even if your container does not have metal in a list of its manufacturing materials, still then make sure to check for some other to materials too. Many cardboard manufacturers use a special kind of waxy inky coating on their products while some use various kinds of glue to help the cardboard pieces stick together. Heating your food for higher temperatures can assist that glue or inky coating in heating up and melting and thus sticking your food. You only want a pizza that is sticky due to cheese, not due to glue!
Secondly, use cardboard boxes in the oven for only small periods of time. These times can be made intermittent but continuous heating for longer periods is simply not recommended.
Last but not the least, do not heat an empty cardboard box (I know this does not make sense, but who knows what can happen when a person is going through a bad day). The reason is that when you heat up cardboard that is containing food in it, then most of the waves are absorbed by the food itself and very few are absorbed by the cardboard box.
When you put an empty cardboard box in it then most of the waves will be directly absorbed by the cardboard box itself and thus the chances of it heating up intensively and thus catching fire, increase dramatically.
To wrap it up, the purpose of this article was not to scare you neither to over-relax you. This is simply mentioning all the pros and cons that you can experience while heating your food covered in a cardboard box.
One just has to be aware that as long as they are using a cardboard container that is microwave-safe then it is no problem in using your cardboard box as a comforting alternative to plates so you don’t have to do dishes!
So, I hope you got the true meaning of the question on “can you put cardboard in the microwave oven?”
Best of luck! 🙂