How to Know What Fridge Food Is—and Isn’t—Safe to Eat After a Power Outage

Hurricanes. Floods. Storms. Any number of things could prompt the loss of power to a residential property. While the lack of internet or lights might be frustrating, the longer-term issue is the fate of refrigerated foods. Once a fridge loses power, it’s only a matter of time before spoilage occurs.

So what do you do with a stocked fridge that’s out of commission?

1. How Long Foods Stay Good During Power Outages
2. Perishable vs. Non-Perishable Foods
3. Planning for a Power Outage

How Long Foods Stay Good During Power Outages

According to the U.S. Food and Drug Administration (FDA) and the U.S. Centers for Disease Control and Prevention (CDC), the broad rule for keeping perishable food safe after losing power in a refrigerator is four hours. For freezers, it’s 48 hours.

But there are some important asterisks to consider. These estimates assume you keep the doors to the appliance closed. When opened, you’ll be letting cold air escape, hastening the rise in temperature.

The quantity of food in your freezer matters, too. Per the FDA, a half-full freezer might only maintain a safe temperature for 24 hours. That’s because cold items tend to act as insulators for other cold items. The more you have, the longer it will take for the temperature to rise.

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But how do you know whether the appliance has remained at a safe temperature? The FDA recommends putting an appliance thermometer inside both your refrigerator and freezer compartments. (This feature may be built in on some, but not all, refrigerator models.) This helps establish the appliance is functioning properly and will alert you to temperature drops that could prove damaging to food stock.

Fridges should be kept at or below 40 degrees; freezers, at or below 0 degrees. If cooked or raw food is kept above 40 degrees for over two hours, you should assume it's no longer safe to consume, as pathogens can begin to grow. A closed fridge should be able to keep food from falling into this danger zone for up to four hours, but if your thermometer reads 45 degrees after an hour, then obviously you’re out of luck. (And leftover pizza.)

If you got hit with an outage and don’t have a thermometer, you’re inviting a bit more risk, but following the four-hour rule is generally fine. One thing you shouldn’t do is rely on a sniff or taste test to see if food is still good: Many things can spoil without a noticeable odor or unpleasant taste, and you might wind up consuming bacteria. But if freezer items still have ice crystals on them, that means they haven’t thawed into a dangerous temperature zone and are likely safe.

Perishable vs. Non-Perishable Foods

Not everything in your fridge will fall under the four-hour rule. Most condiments (excepting mayonnaise or anything made with eggs) are shelf-stable, so there’s no need to toss ketchup or oil-based salad dressings.

Meat, seafood, leftovers, softer cheeses, and dairy are obviously different. Once they’re no longer cold, they’re no longer safe to eat, even if you cook them immediately, although the FDA does make one allowance: If food has risen to 45 degrees but is then prepared right away, it’s probably safe to consume.

Other salvageable and non-salvageable items are listed below.

Anything labeled keep refrigerated is also subject to being discarded.

For freezer items, it’s best to assume anything in it should be tossed after the 24-48 hour rule, though you might be able to refreeze baked breads and fruit juices as well as processed frozen waffles.

Discarding food is never fun. You can probably hold on to more of it, however, if you know a power outage is coming.

Planning for a Power Outage

If an oncoming storm or weather event increases the risk of an outage, you can take steps to protect your perishables. You can freeze water in pans or use gel packs and place them inside the appliance to try and help maintain cooler temperatures for longer. Some people also buy blocks of ice or dry ice for the same purpose, though not everyone may have these readily available.

If you have food you don’t need to consume right away, like leftovers or meats, you can put them in the freezer. Since they’re starting at a colder temperature, it will take them that much longer to arrive at a more concerning temperature.

If your power is expected to remain out for over four hours, you might want to consider moving perishables to a cooler. Your safest best is to use a thermometer to make sure the cooler remains below 40 degrees. If the temperature cannot be maintained, then you’ll have to discard the contents.

One “hack” that won’t work: Snow storms can knock power out, but snow is not an effective insulator. Never try to keep food cold by burying it outdoors. The sun can warm up the ground fairly quickly, making it difficult to know for certain your food is remaining cold.

Obviously, donating food under suspicion of spoilage isn’t an option for humans, but you may find some local zoos will accept perishables for their animals so long as nothing is moldy.

When it comes to food and doubt over whether it’s been kept within a safe temperature range, the old better-safe-than-sorry rule applies: When in doubt, throw it out.