After four hours without power, toss out perishable foods like meat, fish, sliced fruits and veggies, eggs, milk and leftovers, the CDC advises. Any foods with “an unusual odor, color, or texture,” should also be thrown out.
As for the freezer, food will become unsafe to eat after 48 hours in a fully stocked freezer, and 24 hours in a half-full freezer.
“If the power has been out for 4 hours, and a cooler and ice are available, put refrigerated perishable foods in the cooler,” the federal health agency says. “To keep them at 40°F or below, add ice or a cold source like frozen gel packs.”
Foods kept below 40°F can be safely heated or cooked.
Try keeping refrigerator and freezer doors closed as much as possible. If power is suspected to be for a long period of time, dry ice could also help keep foods cold in the refrigerator.