Power Outages and Freezer Failures
Posted: October 29, 2012
Penn State Extension Food Scientists say that a full freezer of food will probably remain frozen for about two days if the door is kept closed. A half-full freezer can only be expected to keep food frozen for a maximum of 24 hours. Check with the utility company to see how long it will take to restore power. If it will be more than one day, consider moving your frozen food to a freezer that is working. You might have a friend or neighbor with extra space in his or her freezer. When your freezer is not full, keep items close together—this helps the food stay cold longer. Freezing water in milk cartons is an easy method of filling space in the freezer.
If another freezer is not available, use dry ice to keep your food frozen. Find out ahead of time where you can purchase blocks of dry ice; don’t wait until the emergency to know if dry ice is even available in your community. A fifty-pound block of dry ice will keep the contents of a full 20 cubic foot freezer frozen for 3 to 4 days. When you buy dry ice, have it cut into small enough sizes to use. Regular ice may help but is not as cold as dry ice. Be sure to handle dry ice with gloves and keep the area well ventilated.
What should you do if the food is thawed? Some thawed food can be re-frozen, but the texture will not be as good. Other foods may need to be thrown away. Temperature is the key to safety. Generally, foods that stay at 40°F or below can be safely refrozen if the color and odor are good and the packages show no signs of spoilage. Examine each item separately. An instant read food thermometer can measure the temperature of a food if you are not sure that it is cold enough. Discard any packages that have been or are above 40°F as they could be unsafe. Generally, if the packages of meat or poultry have ice crystals remaining, it is safe to refreeze them. Discard any packages if juices from thawed meat or poultry drip on them. Refreeze vegetables only if ice crystals are still present. Fruits may be refrozen if they show no signs of spoilage. Thawed fruits may be used in cooking or making jellies and jams. If ice cream is partially thawed, throw it out because the texture of ice cream is not acceptable after thawing and refreezing. Refreeze creamed foods, pudding and cream pies only if they were always at 40°F or below. Breads, nuts, doughnuts, cookies and cakes can be refrozen if they show no signs of mold growth.
Never taste food to determine its safety. Some foods may look and smell fine but may contain bacteria that can cause food borne illnesses. Dispose of spoiled foods by sealing them in a plastic garbage bag or burying the food. And remember, food that is not safe for you is not safe for your pet.
If you anticipate a power outage, it’s a good idea to run the freezer between minus 10°F and minus 20°F. The colder the food, the more slowly it thaws.
Here’s a test to determine if the freezer is off while you are on vacation and you don’t know about it. Put a few ice cubes in a sealed plastic freezer container. If you return and discover that the ice cubes have melted and refrozen as a flat mass in the bottom of the container, you will know that the power was off for an extended period of time, that the food has refrozen, and that it may not be safe to use.
Visit the Penn State Extension Food Safety website at http://extension.psu.edu/food-safety for more information. Or, contact Nancy Routch, Penn State Extension Educator - Nutrition at
(717) 240-6500 or firstname.lastname@example.org.