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When the Power Goes Out, Keep a Lid on Food Safety

KANSAS CITY, Mo. – When the power goes out at home, the clock starts ticking on the safety of meats, seafood, ice cream, cut produce and even leftover pizza.

When refrigerators and freezers suffer a loss of electrical power, the foods inside can become susceptible to foodborne contaminants in just a few hours, said Londa Nwadike, a food safety specialist with University of Missouri Extension and Kansas State Research and Extension.

According to the USDA, bacteria such as E. coli, salmonella, and campylobacter can grow within minutes of food entering the “danger zone” — the temperature range of 40 to 140 degrees Fahrenheit. The insulation in freezers and refrigerators are your best allies during a power failure.

A refrigerator in good working order can maintain its temperature for about four hours, Nwadike said. A full, reliable deep freezer can keep food frozen as long as 48 hours.

“One advantage of winter storms is that we often have 24 hours or more of advance warning,” she said. This lets you take some pre-emptive steps to preserve your food:

Share space with friends. If you have nearby friends and neighbors who have extra space in their freezer, consolidating frozen foods is a great strategy. “A full freezer will maintain its temperature longer than a freezer that’s only half full,” Nwadike said.

Fill in the gaps. If you know a winter storm or blizzard is on the way, consider moving as much as possible from the refrigerator to the freezer. Putting leftover pot roast, tuna casserole and plastic bottles of fruit juice in the freezer will keep these foods in a colder environment and help fill empty spaces in the freezer. You can also use bottles, gallon jugs and plastic storage containers filled with water, Nwadike said. “Just get them frozen before the power goes out. If you have a source for dry ice, consider adding a few blocks to your freezer. Dry ice can extend your safe zone by several hours.”

Keep ’em shut! As much as you can, keep the doors closed, Nwadike said. “Don’t open them to peek in and check to see what the temperature is—just leave them closed. Avoid that temptation.”

After that, the question is simple: Keep it or toss it?

The USDA provides a handy, printable chart ( detailing which foods are most vulnerable (meats, seafood, dairy, ice cream) and which are a bit more stable (whole fruits and vegetables, condiments, hard block cheese).

When checking the freezer, ice can be a good indicator, Nwadike said. “If an item is still frozen solid, or if you can still feel ice crystals, that’s a good thing. But whatever you do, don’t taste something and think, ‘Well, if it tastes OK, it’s still good.’ Bacteria doesn’t always reveal itself that way.”

The old adage holds true: When in doubt, throw it out.

Some homeowners insurance providers will cover a certain amount of food loss that results from a power outage. Nwadike advises homeowners to check with their insurance providers to find out what is covered and what kind of documentation will be required to make a claim.

Even if the loss of food creates a financial hardship, it pales compared to the risks of eating unsafe food, which can result in illness, hospitalization and even death.

For more information and helpful tips from MU Extension, visit