I’ve been wondering if it is safe to use aluminium trays in the microwave for a while now. I have heard conflicting views from various sources, and I’m unsure what to believe, so I thought I would do some experiments and research and share my results with you. Here’s what I found out.
Can You Microwave an Aluminium Tray?
You can microwave an aluminium tray. The Fraunhofer Institute (IVV) in Freising, Germany, conducted experiments into this phenomenon and found no single case of hazardous result or damage to the microwave ovens even when the trays were microwaved at maximum power (1).
However, there are a few things to note if you do decide to use an aluminium tray in your microwave:
- You must remove the aluminium lid before you put the tray in. If you leave the lid on during microwaving, it might lead to arcing, which can damage your microwave oven or even start a fire.
- You must position the tray in the center of your oven so that the tray does not come in contact with the microwave the oven walls for the same reason as above.
- You can only use one tray in your microwave at a time. Do not stack multiple trays or other aluminium cookware in the microwave.
- Lastly, if you use a microwave that has a metal turntable, be sure to place a ceramic or glass beneath the tray to avoid contact between the metal turntable and the tray itself.
What Happens When You Microwave an Aluminium Tray?
I decided to do some experiments to see what happened when I microwaved aluminium trays. When I placed an aluminium tray with food in the microwave, the microwave bounced off the tray and did not seem to pass through to the food.
The only way the microwave could pass through to the food on the tray was from the opening on top. This is the reason why you must not cover the tray with a lid; the lid prevents the microwaves from getting into the food.
Another observation I made was no sparks were seen unless the tray touched the side of the microwave, which could be hazardous to your oven.
What Do The Experts Say About Microwave Aluminium Trays?
To further clarify the safety of microwaving aluminium trays, I did some research and came across a few interesting facts and insights from prominent sources such as the United States Department of Agriculture (USDA) and Fraunhofer Institute for Process Engineering and Packaging IVV in Freising, Germany.
Here’s what the USDA says explicitly about microwaving aluminium trays:
“It can be safe to use small amounts of aluminum foil in a microwave oven.”(2)
This statement is further supported by the study from the Fraunhofer Institute where it stated:
“Based on the physical insight and on empirical findings, all evaluated studies agree that there is no reason to NOT use aluminium foil packages for heating food in the microwave oven – as long as some design rules and heating guidelines are followed.”(3)
But what about the common conception that microwaving an aluminium tray can break your microwave?
From the same study that has been done for the European Aluminium Foil Association, it is stated that:
“safety of microwave over operation is not affected by heating food in aluminium foil trays if instructions are followed. If arcing occurs, it will not damage over or start a fire but may cause minor, aesthetic defects in the over the wall.”
Therefore from the above insights, I can conclude that it is safe to use aluminium trays in the microwaves as long as you adhere to the instructions given.
6 Tips To Safely Heat Food in an Aluminium Tray in the Microwave
As mentioned above, it is safe to use aluminium trays in the microwave as long as you adhere to certain instructions. So below are some helpful tips for using the tray in microwaving safely:
- Aluminium tray must be placed in the center of your microwave so that it does not touch any side of the microwave walls.
- Only use a shallow aluminium tray that is no more than 2 inches deep. This is to make sure that the food is heated evenly.
- Never microwave an empty aluminium tray. You must always put some food on the tray, and the food should cover at least about 75% of the surface of the tray. This is because, without food, there is nothing that absorbs microwaves making the microwaves bounce back and forth to the oven walls, which could cause damage to your oven.
- Do not leave the microwave unattended while you are heating food in an aluminium tray. If arching occurs during microwaving, you need to be around to switch off the microwave immediately.
- Leave the top of the aluminium tray open. If you put something like foil on the aluminium tray, the heated aluminium tray can potentially make the foil go up in flames.
- Last but not least, if your microwave is equipped with a metal turntable, you need to put a ceramic or glass under the tray so that it does not come into contact with the metal turntable. This is to avoid sparks from happening.
Can Microwaving Food In Aluminium Cause Cancer or Health Issues?
This is another issue that has been lingering in the minds of many people, and for this issue will be sharing with you the insights from two other sources :
1. A study published by Deutsches Ärzteblatt International — the German Medical Association’s official international bilingual science journal summarized that the body absorbs only 0.1% of orally injected aluminium. This is a very small percentage, and there has not been enough evidence to prove that this dose triggers or causes health issues. (4)
2. The European Food Safety Authority (EFSA) and the World Health Organization (WHO) have also stated that it is tolerable to ingest between 1-2 mg of aluminium per kg of body weight weekly without any health issues.
In summary, it is safe to use aluminium trays when microwaving your food. Providing you follow the safety instructions closely, it is unlikely that you will face any safety issues or cause damage to your microwave oven.
Healthwise, it is safer than microwaving food in plastic, paper, or styrofoam containers, and there is no proof that microwaving food in aluminium trays causes cancer or health issues.
So there is no reason why you can’t heat up your favorite food in an aluminium tray in the microwave oven.