Can You Put a Metal Bowl in The Microwave?

Your choice of the bowl to use in the microwave greatly determines your heating experience.

A microwave-safe bowl will give you the best results while a microwave-unsafe bowl might cause unintended consequences.

But can you put a metal bowl in the microwave or not?

Well, read through our elaborated write-up to understand what happens when you put a metal bowl in the microwave.

Can You Put a Metal Bowl in The Microwave?

Never put a metal bowl in the microwave oven. Most metals are considered microwave-unsafe unless they have a microwave-safe symbol.

Metal bowls are not the best for microwaving food and if you have used them before without any consequences, just consider it as pure luck and never use your ignorance to justify your action.

Metals tend to reflect heat waves instead of absorbing them thus, the microwaves intended to heat the food do not penetrate the thick metal walls.

No metal is safe when it comes to microwave use. Thick metals block the microwaves meant to warm food while thin metal sheets are a fire risk.

Additionally, metal bowls with uneven surfaces are likely to cause arcing which can cause a fire in the microwave.

Even when the metal bowl does not cause fire, it remains inconvenient because it does not warm the food. The heat waves are blocked from reaching the food.

Some metals like stainless are considered safe for microwave use to some extent. 

Some people argue that stainless steel is a safer metal because it has a coating that enhances its safety.

However, steel is not 100% safe but it can be microwaved with a lot of caution. Stainless steel might not be as hazardous as ordinary metal.

However, it takes more time to heat food in a stainless steel container since steel is a heavy metal. The temperatures too must be set to optimal to heat the food well.

Steel is a very reactive metal that releases ions, especially when exposed to heat. When the released ions interact with food they change its flavor and taste.

These are the things to consider should you choose to microwave your food using a steel container:

  • Always look out for a microwave symbol, usually 3 wavy lines at the bottom of the container.
  • In case the symbol is missing, look out for guidelines for heating metal using a microwave on the appliance’s user-guide manual.
  • Remove the lid while heating food to allow the microwaves to penetrate the wall of the bowl into the food.
  • Since steel is just as strong as ordinary metal, you need to maintain optimal oven temperatures to make sure food is evenly heated.
  • The steel bowl must be of a regular shape without pointed edges, dents, and rust.

A study by the European Aluminum Foil Association (EAFA) also recommends aluminum containers as microwave-safe and the best alternative to ordinary metal containers.

However, never overheat Aluminum because it tends to release toxins that can leach into your food causing contamination.

Some research also confirms that modern microwave appliances have been modified to accommodate metal containers.

This gives us an allowance for using metal bowls but with a lot of moderation.

What Happens When You Put a Metal Bowl in The Microwave?

Metal surfaces tend to reflect heat waves that hit them. The microwaves might not penetrate a thick metal bowl to heat the food.

This makes the metal bowls inefficient because the main objective of microwaving food is to heat it.

Additionally, too much heat might cause the metal surface to release electrons.

Once the electrons are heated, they tend to move rapidly back to the microwave walls. The back-and-forth reflection of the electrons makes them become charged, forming an electric current.

The electric current can be strong enough to spark a fire. The fire can be big enough to damage the appliance or set the entire kitchen ablaze.

Also, some metals release toxins when heated. The toxins can leach into the food rendering it harmful for consumption.

Thin-walled metal bowls too are not ideal for microwave use. Thin metal tends to heat up quickly and might end up causing a fire.

It is even more risky to use a metal bowl with uneven edges because the electric current tends to build up around those sharp pointed edges.

However, regular-walled microwave-safe metal bowls can be microwaved under maximum precaution. The bowl must be free from scratches, dents, or even rust.

Why Is It Dangerous To Put a Metal Bowl in The Microwave?

The back-and-forth reflection of the microwaves from the oven’s walls to the metal bowls causes a mirror effect that damages the oven’s circuit.

The heat build-up on pointed edges can cause a fire that will further damage your appliance.

Some metals interfere with the trajectory of microwaves. The charged electric current causes holes in the walls of the appliance.

Steam from the heating food can cause an explosion if it interacts with the electric current produced by the oven and the bowl.

Thick bowls tend to absorb heat and can cause serious burns on your hands.

What Are The Precautions To Observe Should You Microwave a Metal Bowl?

The following are the safety measures you need to keep in check if you microwave a metal bowl:

  • Place a paper towel under the metallic bowl. The paper towel helps to absorb excess steam from the food.
  •  If the steam is left unabsorbed, it is likely to interact with the electric current causing an explosion.
  • Always observe temperature when reheating food in a microwave using a metal bowl. Metal tends to heat up faster and it can cause a fire.
  •  Since most of the heat is absorbed by the metal bowl, you need to prolong the heating time to ensure your food attains the desired temperature.
  •  However, if you must extend the heating time beyond the recommended microwave time (30 seconds) do it at intervals.
  • Always place the bowl in the microwave lying flat and away from the oven’s walls.
  • The metal bowl should be placed at the center such that its walls do not rub the walls of the microwave.
  • Do not leave metal spoons inside the metal bowls because it leads to the concentration of the electric current and increases the chances of fire.
  • In case you hear unusual sounds from the microwave, consider it as a warning and switch off the appliance promptly.
  • Leave the door closed until the metal bowl cools down.
  • Use oven gloves to remove the hot metal bowl from the oven to avoid burns.

What Type Of Bowls Can Go in The Microwave?

Glass bowls are the most ideal for microwave use since they allow the microwaves to penetrate through them and heat the food.

Glass is safe because it does not emit any chemicals when exposed to heat. It retains its initial nature even under high microwave heat.

The glass bowls allow the food to heat evenly especially when the bowl is not covered with a lid.

They can also withstand high microwave heat without breaking or causing a fire.

Ceramic and plastic bowls too can be used instead of metal bowls.

They too can withstand high temperatures without sparking a fire.

They also allow food to warm evenly since they do not reflect nor absorb microwaves meant to heat food.

Such bowls are unlikely to cause serious burns since they allow heat to pass on to food rather than retain it.

Final Thoughts

Most metals are generally microwave unsafe and not recommended for heating food.

Metals have thick walls that absorb microwaves intended to heat the food so the food ends up being unevenly heated.

The back-and-forth reflection of microwaves causes an electric current that can cause a fire.

It is therefore advisable to choose a more microwave-safe container like glass or ceramic dishes to warm your food.

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