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If you're considering putting aluminum foil, metal trays, popcorn bags, or anything containing metal inside your microwave oven, read this essential guide.
After all, not all foods and the metal materials they're packaged in are safe to use in microwaves, even in highly rated small microwaves.
We'll explain how you can safely put metal in the microwave and how to properly heat things up without them melting from the radiation.
Most microwaves come with an owner's manual, which details which materials you can and cannot use inside your microwave.
Some materials that have different compatibility levels depending on the microwave model are aluminum foil, a metal bowl, or other smooth metal-material containers.
Check the packaging or container itself to see if it's microwave safe. You don't want to heat unstable plastic material in a high-powered microwave.
You can usually see the labels like the one pictured above if it is deemed safe to put inside the microwave. Use only plastic containers that have this label or labels similar to it.
Step 3. Use USDA-Approved Containers and Materials
You can study the USDA's list of safe and unsafe containers for microwaving. They test these materials to see if they are better at reflecting or absorbing microwaves.
They also test to see if they emit poisonous chemicals that can endanger you and your family when irradiated.
Step 4. Check Your Food Manufacturers’ Instructions
Avoid using any thin sheet of old crumpled foil with sharp edges close together. This will cause electricity to arc between them, which is a fire hazard.
What Really Happens to Metal in the Microwave?
You might be asking yourself why some metals are unsafe to use in the microwave. We'll dispel some microwave myths here too.
Unlike what microwave myths say, not all metal will explode in the microwave. It will only arc with electricity jumping from metal to metal if they're close enough.
While food particles like water, fat, and sugar molecules efficiently absorb electromagnetic waves from the microwave, metal doesn't act the same way.
Metal in the microwave has a lot of negatively charged electrons. These become loose electrons that get attracted to other metals close by. This is what causes the arcing.
What Kind of Metal Is Microwave-Safe?
Avoid sticking thin metal foil inside a microwave, especially if it's crumpled. This will cause more arcing electricity between them, and the metal clump heats up quickly.
On the other hand, thick metal is safer to use because the thicker metal heats slower. It is less likely to cause static electricity arcing between points.
Which Containers and Materials Are Microwave-Safe?
You should avoid sticking metal that's thin and crumpled because it will lead to electricity arcing between the sharp points.
Don't stick china with delicate golden glaze or other food receptacles that have metal trim unless they're labeled explicitly as microwave-safe.
You can keep the metal rack that comes with the microwave. It's designed to be used with the appliance.
You can put metal-lined pouches like popcorn bags and Hot Pockets. They steer bouncing electrons back into the food to heat them better.
Safely Microwave Metal FAQs
You might still have questions about microwaving metals and other materials after reading about it. We’ve answered the most commonly answered questions below.
What Are Other Unsafe Materials to Microwave?
One material that falls into absolute microwave no-no materials is polystyrene foam, which is widely known as Styrofoam. It can melt and release harmful chemicals into the air.
Also, avoid putting cold storage tubs meant to hold foods like yogurt. They aren’t safe to microwave and might also release chemicals into the air.
What Food Should I Not Heat in the Microwave?
Don’t heat hot chili peppers in the microwave. They will give off retina-burning chemicals that will stay in the air and irritate your eyes for a while.
Hard-boiled eggs and grapes will both explode in the microwave because the electrons can’t escape once they get inside.
We hope this guide has clarified what you should and shouldn't do with metals in the microwave. The important thing to remember is: when in doubt, don't microwave it.
