When you buy fresh produce or a package of chicken thighs, you’re probably just thinking about what recipe you’re hoping to cook with them, and how long you likely have before they spoil. But that mental calculus of how long food is supposed to stay fresh likely doesn’t factor in random disasters, like blackouts, into the equation.
Alas, with the Atlantic hurricane season in full swing, and fire season in the West potentially forcing rolling blackouts, there’s a considerable chance that you might soon lose power yourself—and risk losing everything you have stocked up in your fridge and freezer.
So, what can you do if this happens to you to minimize how much you have to toss? For starters, keep the settings cool in general. “You want your refrigerator below 40 degrees, and freezer at or below 0 degrees before losing power,” says Kelly Jones, RD, a dietitian and food safety expert who taught food safety at Bucks County Community College in PA for nearly 10 years.
If you anticipate power going out (say you get notified of blackouts or know a storm is on the way), you can adjust your settings so that the fridge and freezer are a few degrees cooler than normal.
But once the power goes out, you’re up against the clock to ensure that your food stays fresh. Here’s what to know about food safety during a power outage—and how to mitigate the worst of the impact.
Food safety during a power outage: Your 101 guide
The temperature “danger zone” for food begins above 40 degrees Fahrenheit, as that is when bacteria and other microbes are able to quickly multiply and release toxins into your food. Thus, refrigerated food should be discarded after just four hours without power, says Jones. You get a little more time in the freezer, though. “Food will last in a half-full freezer roughly 24 hours and a full freezer, 48 hours,” she says.
Even if you get your power back within those time frames, you should still thoroughly check all food you intend to consume to make sure it’s still safe to eat. “Check to ensure food is below 40 degrees before preparing or consuming,” Jones says—you can do this with a standard food or meat thermometer.
That temperature check is all-important if you are trying to salvage any food, says Jones.“Since toxins, like botulism for example, have no smell or taste, it isn’t safe to rely on those measures to determine food safety,” she says, so be sure you’re paying attention to temperature before digging in.
Plus, type of food matters too. “Animal products and open bottled beverages are most likely to spoil quickly and are the foods that temperature checks are most important for,” she says. Same goes for leftovers and prepared foods, she says, like soups or cooked vegetables—even if they don’t contain animal ingredients.
Meanwhile, whole fruits and vegetables are the safest outside of the time and temperature windows indicated, so long as they have been stored away from any animal products, and there is no chance of cross-contamination.
All that said, Jones says there are some things you can do to help mitigate the damage and buy yourself a bit more time. But again, be sure to check all food before consuming it with a thermometer. And when it doubt, toss or compost it. Better safe than salmonella.
How to keep food fresh for longer during a power outage:
1. Pre-freeze ice packs and water
If you have a feeling that you may lose power, then you can prepare. “If you’re expecting a big storm, you can freeze as many gel packs and containers of water as possible in advance so that you can use them to keep food at proper temperature for longer,” Jones says. You can also buy dry ice or bags of ice in advance and store them in the freezer.
Then, when power goes out, you can transfer your frozen supplies to the refrigerator. You can also keep your ice packs in coolers nearby. “If the power goes out, transfer the food once the refrigerator or freezer has hit its safe temperature limit,” she says.
2. Stock up your freezer
Keep that freezer full if you can. “A full freezer will stay cold enough up to twice as long as a half-full freezer, so it’s a good idea to freeze whatever you are able to from the refrigerator to extend the safe window of time,” Jones says.
Looking for healthy foods to flesh our your freezer supply? Check out these healthy picks a dietitian loves:
3. Get a thermometer
No matter how you are trying to preserve food, it’s important to have a well-functioning appliance thermometer to ensure the temperature of the fridge, freezer, or cooler stays below 40 degrees Fahrenheit. “You can check the temp each time you open them to actually get food so that you limit the number of times you’re opening and letting cold air out,” Jones says.
4. Keep the doors closed
Most importantly: Once the power goes out, avoid opening the fridge and freezer as much as possible to ensure cool air stays inside. “But, know this doesn’t keep your food safe for very long without additional support,” Jones says. This will keep food as cold as it can be, but of course, if it’s been hours and you have certain foods, like dairy, meat or poultry, for example, you might not be able to keep it fresh enough to eat later on.