Margarine tubs, yogurt cups, takeout containers and whipped topping bowls are made for one use. They can warp or melt in the microwave, so move the food to a dish first.
Guidance based on USDA material is clear that one-time-use plastic containers should not go in a microwave. Heat can warp or melt them, and the concern is that chemicals can then migrate into the food. Clemson extension makes the same point for any container that is not labelled microwave safe. Reusing a tub for leftovers is fine in the refrigerator, but not under the microwave.
| Short answer | No |
|---|---|
| Which containers | Margarine tubs, yogurt cups, takeout containers and whipped topping bowls |
| Why | One-use plastic can warp or melt |
| Risk | Chemicals can migrate into the food |
| Exception | Only a container labelled microwave safe |
What to do instead
- Spoon the food into a ceramic or glass dish.
- Cover it loosely with a microwave safe plate.
- Heat in short bursts and stir.
- Wash and keep the tub for the refrigerator or freezer, not the microwave.
- Check the base of any container for a microwave safe symbol.
What happens when you get it wrong
- A warped tub. The container softens and collapses, and hot food spills.
- Melted plastic. It can stick to the food and the turntable.
- Chemicals in the food. Heated single-use plastic is not tested for it.
A glass or ceramic dish for reheating.
A container clearly labelled microwave safe if you need one to carry food in.
Frequently asked questions
Can you microwave a yogurt container?
No. It is single-use plastic that can warp or melt.
Can you microwave a margarine tub?
No. FSIS-based guidance lists margarine tubs among containers that should not be used in the microwave.
What about takeout containers?
The same rule applies unless the container is labelled microwave safe.
How do you know if plastic is microwave safe?
Look for a microwave safe mark on the base. If there is none, use a glass or ceramic dish.