4 Best Insulated Food Containers, Tested by Our Experts

An insulated food container stacks the odds more in your favor because it’s designed to retain hot and cold temperatures for longer. But as CR discovered when testing eight insulated jars in our labs, they’re only as good as their ability to retain temperatures and not leak chicken soup all over your bag. We tested some of the things you might be concerned about when carrying an insulated food container around town—including insulation and leaks, and how well a jar can eliminate the lingering smell of chili (talk about a challenge). We even performed a drop test, and we’re happy to report that all the containers survived. We learned that no single jar is perfect, but four rose above the rest.

Some insulated jars come with specific claims about how long they can be relied on to maintain consistently hot or cold temperatures. Tracking temperatures is important, not just because you want to enjoy your meal at a reasonably warm or cold temperature, but because the Department of Agriculture says that keeping hot food at or above 140° F can prevent it from developing bacteria and falling into the “danger zone.” Keeping cold food at or below 40° F is also recommended to help prevent bacterial growth.