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Food Safety and Power Outages

Safe food handling is important in everyday life. In an emergency, like a power outage, it is especially important.  

Be Prepared

If you know that the power will be out:

  • Have an appliance thermometer in the refrigerator and freezer or a digital quick-response thermometer. A digital thermometer is very useful in the kitchen because it can quickly check the internal temperatures of food for adequate cooking and safety.
  • Keep on hand a few days worth of shelf-stable foods, such as canned goods and powdered or boxed milk.
  • If the power outage will be longer than 2 to 4 hours: get ice and/or dry ice. Fill one or more coolers with ice. Styrofoam coolers also do an excellent job.

During the Power Outage

  • Keep the refrigerator door closed! Refrigerated foods are safe as long as the power is out for no more than four hours and if the door is kept closed. Always keep meat, chicken, fish and eggs refrigerated at or below 40 °F and frozen food at or below 0 °F. 
  • A full freezer will keep food frozen for about 48 hours. A freezer that is half full will keep food frozen for about 24 hours.  The kind of food in the freezer makes a difference; meats and vegetables will stay frozen longer than bread. To preserve food in your freezer, keep the door closed as much as possible.
  • If the power outage is more than 2-4 hours, pack the important items in your refrigerator, such as milk, dairy products, meats, fish, poultry, eggs, and leftovers into your cooler surrounded by ice.
  • If the power outage will be longer than 24-48 hours, prepare another cooler with ice for the items in your freezer.
Once the power comes back. be sure to carefully inspect all food items and do not eat any food you think may not be safe. Spoiled food may not look contaminated. Remember, when in doubt, throw it out.

When the power is restored, check all food accordingly. 

  • Never taste food to determine its safety. 
  • If an appliance thermometer was kept in the freezer, check the temperature when the power comes back on. If the freezer thermometer reads 40° F or below, the food is safe and may be refrozen.
  • If a thermometer has not been kept in the freezer, check each package of food to determine its safety. You can't rely on appearance or odor. If the food still contains ice crystals or the temperature can be measured and is 40° F or below, it is safe to refreeze or cook.
  • Refrigerated food should be safe as long as the power was out for no more than 4 hours if the door was kept closed.
  • Discard any perishable food (such as meat, poultry, fish, eggs or leftovers) that has been above 40° F for 2 hours or more.

Frozen Food, when to save and when to throw out...

​Food​If it has ice crystals and feels as cold as if refrigerated​Thawed and held above 40°F for > 2 hrs
​Beef, veal, lamb, pork, and ground meats, poultry and ground poultry, variety meats (liver, kidney, heart, chitterlings), casseroles, stews, soups, eggs (out of shell) and egg products, shredded cheeses, cream, soft cheeses, cheesecake, cakes, pies, pastries with custard or cheese filling,, frozen meal, entree, specialty items (pizza, sausage and biscuit, meat pie, convenience foods) ​Refreeze ​Discard
​Fish, shellfish, breaded seafood products​Refreeze. (some texture and flavor will be loss)​Discard
​Milk, Cheese (soft and semi-soft)​Refreeze. (some texture will be loss)​Discard
​Ice cream, frozen yogurt​Discard​Discard
​Hard cheeses, flour, cornmeal, nuts, Breakfast items –waffles, pancakes, bagels, Breads, rolls, muffins, cakes (without custard fillings)​Refreeze ​Refreeze

Refrigerated Food, when to save and when to throw out...

​Food​Held above 40°F for > 2hrs
​Raw or leftover cooked meat, poultry, fish, or seafood; soy meat substitutes, thawing meat or poultry, salads, meat, tuna, shrimp, chicken, or egg salad, gravy, stuffing, broth, lunchmeats, hot dogs, bacon, sausage, dried beef, pizza – with any topping, canned hams labeled "Keep Refrigerated", canned meats and fish, opened casseroles, soups, stews, soft cheeses: blue/bleu, roquefort, brie, camembert, cottage, cream, Edam, Monterey Jack, ricotta, mozzarella, Muenster, Neufchatel, queso blanco, queso fresco, shredded cheeses, low-fat cheeses, milk, cream, sour cream, buttermilk, evaporated milk, yogurt, eggnog, soy milk, opened baby formula, fresh eggs, hard-cooked in shell, egg dishes, egg products, casseroles, soups, stews, potato salad, vegetables, cooked; tofu, Vegetable juice, opened, Baked potatoes, commercial garlic in oil, custards and puddings, quiche, fresh fruits, cut, fish sauces, oyster sauce, and opened creamy-based dressings​Discard
​Hard Cheeses: Cheddar, Colby, Swiss, Parmesan, provolone, Romano​Safe
​Processed Cheeses​Safe
Grated Parmesan, Romano, or combination (in can or jar)​Safe
​Butter, margarine​Safe
​Opened mayonnaise, tartar sauce, horseradish​Discard if above 50°F for > 8 hrs
​Fresh fruits, coconut, raisins, dried fruits, candied fruits, dates​Safe

For a complete list, please visit:

Boston Public Health Commission
1010 Massachusetts Ave, 6th Floor, Boston, MA 02118.
Phone:(617) 534-5395 Email: