When you want to quickly reheat food without having to use plates or do extra washing, using cardboard in the microwave is a great option. In general, can you microwave cardboard, but there are a few important precautions to keep in mind.
To begin, make sure you never microwave an empty cardboard container – or plain cardboard of any kind – without food or liquid. Under supervision, you should microwave pure cardboard containers with food or drink. Microwaving cardboard containing plastic, wax, ink (unless the label says otherwise), glue, or metal, on the other hand, is not recommended. Stop overheating by not placing cardboard in the microwave without any food or drink. If heated to a sufficiently high temperature without food or liquid to absorb the microwave’s energy, cardboard, and other paper products may cause steam explosions.
Second, make sure there are no metal pieces in the cardboard bag. Metal handles, for example, can be found on several Chinese restaurant take-out cardboard containers. Microwaving these is never a good idea because the metal handles can spark and ruin your microwave. Metal particles and sparks can often be found in recycled cardboard, although this is rarely the case for food containers.
The products paper and cardboard are flammable. As a result, there’s a chance the cardboard container will catch fire or burn when you heat food in the microwave. However, since it retains water and food moisture, it has a low risk of catching fire if heated for too long.
Another concern with can you microwave cardboard is that certain boxes contain or are covered with plastic. Although it is not a normal occurrence, search for a plastic or wax coating on cardboard before putting it in the microwave. It might not be microwave-safe if it feels overly sticky or smooth to the touch, as it may emit poisonous fumes or partially melt.
Chemicals are another danger you’ll have to deal with. Recycled materials are used in some cardboard containers. As a consequence, the metal that is not microwave safe can be present in your food cardboard containers. As a consequence, always check the labels of your food containers before microwaving them.
Even if you’re sure your cardboard is safe to microwave, you can always keep an eye on the food or drink you’re reheating. When liquids are microwaved for an extended period, they would become superheated and burst. While it is highly improbable to harm your device, opening the microwave or consuming the liquid creates safety when using a cardboard box.