Safe microwave practices matter when heating food. One question that comes up a lot is: Can cardboard go in microwave? Read this article to go through the details and understand clearly whether you can microwave cardboard, and what precautions you have to take.
Is Cardboard Microwave-Safe?
Paper pulp: Pizza boxes, takeout containers and ready-meal packaging – cardboard is widely used as a food package. Generally speaking, most types of plain cardboard containing no coatings or additives can survive the microwave for a short duration. But there are a number of things you should keep in mind before microwaving cardboard.
Is it Safe to Microwave Cardboard? Things to Keep in Mind
1. Type of Cardboard
Not all cardboard is created equal. Uncoated cardboard without glue, or printed designs is fairly safe to microwave. However:
- Wax-coated or laminated cardboard may emit toxic compounds when heated.
- Printed cardboard may use inks that are unsafe for microwaving.
2. Presence of Metal Components
Certain cardboard containers, like takeout boxes, can have those metal handles or linings. These are not safe to microwave, because metal will spark and can ruin the microwave or start a fire.
3. Food Residue and Grease
Cardboard with food residue, especially grease, presents another risk. Grease can spark quickly and catch fire, particularly in older microwaves or at high power settings.
4. Microwave Duration
If cardboard is microwaved for a long time then there is higher risk of burning. If you must heat food in a cardboard container, keep times under two minutes and watch closely.
Microwaving Cardboard: Tips and Best Practices
1. Check Labels
Microwave caution labels — A lot of food packages include labels that ask if it’s microwavable. Look for phrases like “microwave-safe” or a microwave symbol.
2. Try Low to Medium Power Settings
Never use high power settings when heating food in cardboard. Using lower to medium heat can help prevent burning.
3. Transfer Food When Possible
If you’re unsure whether a cardboard container is safe, transfer the food to a microwave-safe dish or plate. Microwaveable storage utensils could be glass or ceramic containers.
4. Avoid Empty Cardboard
It is unsafe to microwave empty cardboard. Always put food or liquid inside the container so that the microwave energy can be absorbed by something.
Is It Safe To Microwave Cardboard? Potential Hazards
Although microwaving cardboard seems like a convenient option, there are risks associated with it:
- Fire Hazard: If cardboard is exposed to high temperature for an extended period of time, the cardboard can catch fire.
- Chemical leachates: Not only leachates from cardboard, but coatings, adhesives or inks used on cardboard can also release harmful chemicals at high temperatures.
- Uneven Heating: Cardboard is not a great heat conductor, which can result in food that isn’t evenly warmed.
Other Microwave-Safe Containers
But if you’re still unsure about putting cardboard in the microwave, here are some alternatives:
- Microwave-safe labeled glass containers.
- BPA-free microwave-safe plastic food containers
- Microwave-safe ceramic dishes
Conclusion
So what about putting cardboard in the microwave? The answer is: it depends. Although plain uncoated cardboard is typically safe to heat for short times, its always best to look for microwave safe labels and use your best judgement. Since you should never put any plastic containers in the microwave for safety and to encourage even heating, the best option is to transfer to a microwave-safe container before warming.
If you follow these guidelines, both your food safety and the longevity of your microwave will be well provided for.
