The truth about reusing takeout containers

If you enjoy takeout and food deliveries, you might find your kitchen swimming with plastic food containers. And while some orders come in a single-use carton or styrofoam boxes that you just toss, others will have been served up in containers that might be too sturdy to be single-use. Should you save those? 

Food professionals appear to love their takeout food boxes because they can be versatile, and because glass containers aren't allowed in most kitchens (they break). Chef Jeremy Umansky is partial to reusable deli containers because they can hold just about all kinds of food from sauces to fried rice, but also because they can be used as organizers for small kitchen equipment, whose parts can fall and hide under a prep counter or cabinet. As Food 52's Allison Bruns Buford puts it, "If you are in possession of the full range — a quart, pint, half-pint — you basically have a container to suit every storage need," not just because they stack well but also because there's nothing else like eating directly out of one (via Food52). 

If you're the type of person who enjoys keeping leftovers or pre-prepared meals in recycled deli food containers, there are a few things food scientists think you should know. 

Avoid reheating food in takeout containers

Deli containers are made with polypropylene, which is the second-most used plastic after polythylene, which is what plastic bags are made of. "Polypropylene, as plastics go, is supposed to be one of the 'safer' plastics," Caroline Cox, a scientist with the California-based Center for Environmental Health says. "One of the biggest problems is we don't really know what's in these containers and neither do the restaurants that are using them." This is compounded since other chemicals are added to raw plastic before they are turned into deli containers (via Epicurious). 

All these chemicals shouldn't cause any problems when takeout boxes are used to store dry goods like rice or beans. They can also be used safely in freezers, because they can be exposed to sub-zero temperatures for a long time. But while they can be labeled freezer- or dishwasher-safe, Cox says it isn't a good idea to put deli containers in microwave ovens, because that's where any toxins could leach out of the plastic. "There's a fairly big gap in the knowledge available to people about plastics and food safety," Cox tells Food52.

If you take good care of your takeout boxes, they have a few months of life in them. And you'll know it's time to say goodbye when the boxes get cracked, warped, discolored, or smelly.