Here's How Long A Lunchbox Will Keep Your Food Fresh

Packing a lunch for a day at the beach? That's nothing. Dig out the cooler from storage, load it with some ice, toss in some waters, grab your favorite cold cuts and fruits and you're good to go. But let's face reality: If you're regularly trying to keep a packed lunch cold, it's probably to make it through the work or school day – and not a day on the shore (we wish, though).

According to the USDA, "Foodborne illness can multiply rapidly at temperatures between 40 degrees F and 140 degrees F." Perishable foods can reach temperatures in the danger zone in as little as two hours. That's nothing compared to the time a morning commute might steal from your day. Don't waste another day of your prized PTO on another bout of avoidable food poisoning! Whether you're headed into the office or sending your kids on the bus, keep these tips and timelines in mind to keep your lunch safe and fresh in a lunchbox.

The amount of time your food stays fresh depends on how cold your lunchbox is

Two hours might not be nearly enough time to keep a lunch cold, once you take into consideration the occasion that you're packing for. In an article for The Kitchn, Ayn-Monique Klahre said that her daughter had about four hours between leaving the house in the morning and opening up her lunch bag. That's double the amount of time that the USDA warns could make perishable food unsafe.

The Kitchn also spoke with the International Food Information Council Foundation's director of food technology communications, Dr. Tamika Sims, who explained that it's completely possible to extend the life of your lunch with the proper planning. The key lies in having a cold source – no matter what box or bag you carry, you'll need a completely frozen ice pack to go along with it. The more food you're packing, the more cold sources you'll need.

If you don't have an ice pack, you can always DIY one at home by filling an old water bottle up and freezing it. As long as you add a cold source, you should expect your food to stay fresh for up to four hours – just in time for lunch.

You don't need a fancy lunchbox to keep your food chilled

Dr. Sims told The Kitchn that the best bet to keep your food safe for the longest time is "an insulated, soft-sided lunch tote ... especially if you use a cold source in there." Sure, metal bento boxes are trendy and aesthetically pleasing, but they don't do as good of a job protecting your perishables.

According to the Laborers' Health and Safety Fund of North America, you should opt for an insulated lunchbox or bag when possible. If that's not an option, a metal or plastic box is a safe second choice, as long as there are one or two cold sources tossed in the mix.

The site also recommends avoiding a bagged lunch. We've all been there: rushing out the door, late to your first meeting or bus drop-off, and aimlessly grabbing a plastic grocery store bag to toss your ham and cheese sandwich in. It's not worth getting sick, but if you're in a real rush, at least double up on the bags to help insulate and keep your cold sources frozen – and try to enjoy your sandwich before four hours are up.