Can you put aluminum foil in a microwave

More than 14,000 social media users have been sharing a post which advises people to wrap eggs in aluminum foil before putting them in the microwave to boil them. However, it is dangerous to put foil in a microwave as it will spark and could cause a fire. Hard-boiled eggs should also not be reheated in a microwave as they will likely explode.

Various models of microwaves sit in a testing room at the Nestle Development Center in Solon, Ohio, U.S., April 24, 2018. Picture taken April 24, 2018. REUTERS/Aaron Josefczyk

The posts (here  ,  here  ,  here) show two pictures, one of hard-boiled eggs and the other of eggs wrapped in foil with the caption “Tip: wrap your eggs in aluminum foil and microwave for 2 minutes, wayyy quicker!” 

Comments and captions show that while some people recognise this would be dangerous (“Everybody know you don’t put aluminum foil in the microwave”; “Hope these people don’t actually fall for this”; “People nobody do this”), others are potentially taking the advice seriously or are unsure whether to take it seriously or not: “Can you really put aluminum in micro????”; “Doing it as we speak”; “Hmm… won’t the foil blow up in the microwave?”

The U.S. Department of Agriculture’s (USDA) Food Safety and Inspection Service (FSIS) explains on its website that “no food completely covered in foil or in a covered metal pan should be put in a microwave oven because food won’t be able to absorb the microwaves. Operating the oven empty or when the food is completely wrapped in aluminum foil can cause damage to the oven and the food won’t heat” (here). The FDA reiterates that food completely covered in aluminum foil should not be put in the microwave here  .  

The electric fields in microwaves cause charges to flow through metal. Thin pieces of metal like aluminum foil are overwhelmed by these currents, causing them to heat up so quickly that they can ignite. If the foil has sharp edges or crinkles the currents can form sparks, which can also start a fire (here  ,  here  ,  here). 

Videos of what happens if you put aluminum foil in the microwave can be seen here and here  . 

Hard-boiled eggs that have been reheated in the microwave can explode when they are pricked or someone bites into them (here  ,  here  ,  here). There is no scientific consensus as to why this happens.  

Examples of this occurring can be seen in videos here  and here  . 

Advice on how to use a microwave to cook eggs does not feature the use of aluminum foil and can be seen here and here . Pricking a small hole in the egg to avoid it exploding is advised.  

VERDICT

False. Aluminum foil should not be put in the microwave as it can cause a fire, and hardboiled eggs should not be reheated in the microwave as they will likely explode.

This article was produced by the Reuters Fact Check team. Read more about our fact-checking work  here  .

Aluminium containers can be used to pack food because they are safe for use in direct contact with food. To store aggressive foods (salty or acid) the best solution are the lacquered aluminium trays. In addition, aluminium provides a 100% water and gas barrier. More than this, all trays are 100% recyclable.

Aluminium containers can be also used for oven cooking because this material distributes heat homogeneously avoiding the risk of cracking or melting the container.

Can I use aluminium containers in the microwave?

Aluminium trays can be used in the traditional oven and in the microwave. A study by the Fraunhofer Institute (IVV) in Freising, Germany established that aluminium foil packaging can be safely used in microwave ovens. “The Fraunhofer Institute conducted the heating procedures with the microwave ovens set at maximum power and there was not a single case of damage to the microwave ovens or danger to the user”, said Thomas Pfeiffer, the study’s author.

How to use aluminium containers in the microwave

Aluminium lid must be removed from the tray before use. You have to place aluminium container in the middle of the turntable in the microwave oven because the container must not come into contact with the walls of the microwave. If your microwave is equipped with a metal turntable, you should place a ceramic or glass plate beneath the tray: no contact between the two metallic objects. And last but not least, only one tray at a time must be used in the microwave oven.

Is it safe to put aluminum foil in the microwave?

Why does aluminum foil spark in the microwave?