The microwave is a pretty miraculous device. Perfect for leftovers, the appliance is a staple in many a kitchen. However, some containers—and surprisingly some foods—do not belong in a microwave.
It is pretty common knowledge that aluminum foil should not be put in the microwave because it's flammable, but many other materials are equally as flammable. Did you know that stainless steel travel mugs shouldn't be microwaved either? It's not only harmful to the appliance, but as it turns out, the steel prevents the heat from warming up the liquid, so it won't actually heat up your drink.
There are also a few less obvious items you shouldn't put in the microwave. Did you know that Styrofoam is a type of plastic? That means that it's not microwave safe. Bags are also definitely a big microwave no-no.
Not only can plastic bags cause a fire, but they can emit toxic fumes too. Paper grocery bags aren't any better—they're flammable too!
If you think it's just containers you need to avoid putting in the microwave, think again. Certain fruits can catch fire in the appliance too! Raisins will begin smoking if microwaved. (So it makes sense that grapes can't go into the microwave either for the same reason.) Eggs in the shell could also explode in the microwave due to the rapid pressure of the heat.
However, what may be the strangest thing of all to not microwave is...nothing. Turning the microwave on without putting anything in it will damage the device. Without any water molecules to absorb the microwaves, the appliance itself can get really damaged.
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