Food Safety Before, During and After a Power Outage

Published on July 26, 2022 by AMY HENDRICKSON

The weather has caused power outages across the United States already this year.  There are certain things that you can do to before, during, and after a power outage to help keep your family food-safe. 

Prepare Yourself Before Power Emergencies

  1. Make sure you have appliance thermometers in your refrigerator and freezer.  Check to ensure that the freezer temperature is at or below 0° F, and the refrigerator is at or below 40° F.  In case of a power outage, the appliance thermometers will indicate the temperatures in the refrigerator and freezer to help you determine if the food is safe.
  2. Freeze containers of water for ice to help keep food cold in the freezer, refrigerator, or coolers in case the power goes out.  If your normal water supply is contaminated or unavailable, the melting ice will also supply drinking water.
  3. Freeze refrigerated items such as leftovers, milk, and fresh meat and poultry that you may not need immediately.  This helps keep them at a safe temperature longer.
  4. Group food together in the freezer.  This helps the food stay cold longer.
  5. Have coolers on hand to keep refrigerated food cold if the power will be out for more than 4 hours.
  6. Purchase or make ice cubes in advance, and freeze gel packs ahead of time.  Store all of these in the freezer for future use in the refrigerator or in coolers.
  7. Check out local sources to know where dry ice and block ice can be purchased, in case it should be needed.
  8. Store food on shelves that will be safely out of the way of contaminated water in case of flooding.
  9. Make sure to have a supply of bottled water stored where it will be as safe as possible from flooding.  If your bottled water has an odor, do not drink or use it.  Instead, dispose of it, or if applicable, call your bottled water provider to make arrangements to get a replacement.

During an emergency, if you use food or beverage containers to hold non-food substances like gasoline, dispose of them after use and do not recycle them.

Power Outages: During and After

When the Power Goes Out . . .  Here are basic tips for keeping food safe:

  1. Keep the refrigerator and freezer doors closed as much as possible to maintain the cold temperature  inside.  The refrigerator will keep food cold for about 4 hours if it is unopened.  A full freezer will keep the temperature for approximately 48 hours (24 hours if it is half full), as long as the door remains closed.
  2. Buy dry or block ice to keep the refrigerator as cold as possible if the power is going to be out for a prolonged period of time.  Fifty pounds of dry ice should keep an 18 cubic foot, fully stocked freezer cold for two days.
  3. If you plan to eat refrigerated or frozen meat, poultry, fish, or eggs while they are still at safe temperatures, it is important that each item is thoroughly cooked to a safe minimum internal temperature to ensure that any food-borne bacteria that may be present are destroyed.  However, if at any point the food was above 40º F for 2 hours or more (or 1 hour if temperatures are above 90 º F) — discard it.
  4. Do not store food or drink outside to try and keep it cold.  Fluctuating temperatures and small animals looking for their next meal can cause food to become unsafe.

Once Power is Restored . . .Determine the safety of your food:

  1. 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.
  2. 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 is 40° F or below, it is safe to refreeze or cook.
  3. Refrigerated food should be safe as long as the power was out for no more than 4 hours and the refrigerator door was kept shut. Discard any perishable food (such as meat, poultry, fish, eggs, or leftovers) that has been at temperatures above 40° F for 2 hours or more.

Perishable food such as meat, poultry, seafood, milk, and eggs that are not kept adequately refrigerated or frozen may cause illness if consumed, even when they are thoroughly cooked.  Stay warm and food-safe!

Authored by: Barb Ingham, 608-263-7383, bingham@wisc.edu
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