It’s an age old question. Can you put aluminum foil in the microwave?
No, you cannot put aluminum foil in the microwave. Let there be no ambiguity to this: The best case scenario of putting aluminum foil in the microwave is that your microwave is destroyed. The worst case scenario is your house burning down. You are probably wondering how that is.
Why You Can’t Put Aluminum Foil In the Microwave
The effect microwaves have on aluminum can be described in several ways. Some ways of describing this effect are complex, some are quite simple. To begin with, consider this simple reason: Aluminum catches fire in the microwave. That is a thing that happens 100% of the time. Do you need to know why? No, not really.
There is no way around this. There is no lifehack, no clever trick, no single thing that can be done to get around this. If this article is seeming like it is repeating itself, consider who might usually be asking whether or not you can put aluminum foil in the microwave.
Most of the time, it is going to be people who want to do it. The people who ask that question are going to be the kind of people who think they can outsmart science. They think they can figure out some way that somehow no one has ever thought of that can make aluminum safe in microwaves.
It is for that pathetic life form that articles like these must be repetitive and unambiguous. It begins to sound like a Dr. Seuss book. You cannot put aluminum in the microwave over there. You cannot put aluminum in the microwave over here. You cannot put aluminum in the microwave anywhere.
But at the same time, there is another, more noble reason to inquire into putting aluminum into the microwave. Perhaps you know that it can burn your house down, but you want to know what causes that to happen. For you, here are some questions that you might want to have answered.
Why Does Aluminum Catch Fire In The Microwave?
Every material in existence has a property called “conductivity”. Conductivity is the material’s ability to convey energy through itself. Imagine you are trying to get electricity from one end of the room to another. Rubber would not be able to transfer that electricity. Metal would do so the best.
Metal is more conductive than basically any other material. Aluminum foil is included among those metals, even though it is so thin it might not seem like a metal at first blush. Metal can contain and pass on more heat than your average material.
Why is the conductivity of metal important? Well, because microwaves utilize something called “microwave radiation” in order to heat food up. This radiation is sent into the food, or whatever else is in the microwave, heating it in accordance with its conductivity.
What is interesting about this is that it means microwaves do not usually heat the food itself as much as they heat the water inside the food. Obviously this causes the food to be heated too, but the water is basically burned as fuel to accommodate this heating process.
Now compare a microwave to a normal oven. Whereas an oven can only heat up a metal so much (the metal will become too hot to touch, but not much worse than that) a microwave will keep heating and heating and heating and heating the metal until it combusts. Tons of heat will be pushed into this metal.
Pop quiz hotshot: What is the combustion point of aluminum? The answer is around 2400 degrees Celsius. That microwave radiation keeps heating the metal more and more till it catches fire. Eventually the aluminum explodes in your microwave, doing so with the heat of a hand grenade.
What Can You Use Instead?
Usually when people want to put aluminum in the microwave it is not just to be funny. They usually want to use it as a sort of makeshift container for their food. This is recommended in many recipes as a way to heat up sandwiches in the oven. It makes use of metals’ conductivity to cook the sandwich all the way through.
Were microwaves smarter, perhaps this would work. But as things are right now, trying to do the same thing in a microwave that you do in a normal oven will just result in things getting too crazy to fix. As such, one must find alternatives to aluminum to make sure their microwaved food is cooked all the way through.
Interestingly, the best alternative to aluminum foil when cooking in the microwave is usually a paper towel. This is interesting because paper towels will usually be the thing to catch fire if they are left in the oven. But in the microwave, which only heats things that are conductive, especially unconductive paper towels are safe.
What the paper towels will do for you is create a greenhouse for the heat generated by your foods’ water. Essentially, the water inside your food will be heated by the microwave. That heat would normally disperse but wrapping it in a paper towel keeps it tightly packed in with the food, heating it better than normal.
The worst thing that might come out of this is the paper towel feeling “sweat” afterwards. This is the result of the vaporized water from the food being absorbed by the towel. It is a little gross, but safe.
So, in short, use a paper towel or paper plate instead of aluminum when microwaving food. It might just save your life.