Mary Donaldson<[email protected]>, Michigan State University Extension -
Updated from an original article written by Jeannie Nichols, Michigan State University Extension.
Food safety is a major concern for food kept in the freezer during a power outage.
What to do about a freezer during and after a power outage? It can be a risk to consider what to keep or toss with the food in the freezer. When the power is restored, it is a relief, but is the food in the freezer still safe to eat?
The risk of foodborne illness is increased when food stored in the freezer is exposed to unsafe temperatures. When the power is restored MSU Extension recommends that the food in the refrigerator and the freezer be inspected. The United States Department of Agricultureprovides recommendations for food.
Time and temperature
MSU Extension and the USDA advises keeping perishable food out of the temperature danger zone for best quality and food safety. Food is preserved and is considered safe if the air temperature measures 0 degrees Fahrenheit or lower in the freezer. When the power goes out, a full freezer will keep the temperature for approximately 48 hours, or 24 hours if it is half full. This does require the door to remain closed. Always keep an appliance thermometer in the freezer and use it to check the temperature when the power comes back on.
The USDA recommends the following tips to follow:
- Keep food if the appliance thermometer reads 40 degrees Fahrenheit or below and everything still contains ice crystals. The food is safe and may be refrozen. Food that is refrozen will not have the flavor or texture quality of a product that was not thawed.
- Discard food if the freezer appliance thermometer reads more than 40 degrees Fahrenheit. One exception is ice cream. Even if it is 40 degrees Fahrenheit or colder and some ice crystals are observed, it is not recommended to re-freeze ice cream as the quality significantly declines.
The taste/smell test
Many people believe that smell and taste is an indicator that food is no longer safe. There are two types of bacteria, spoilage and pathogenic, that are commonly found in refrigerated foods. Spoilage microorganisms can create smells and flavors that cause the quality of food to be undesirable. Pathogenic microorganisms, the “germs” that cause foodborne illnesses, do not make their presence known. These microorganisms cannot be seen with the naked eye, nor have a distinct smell or flavor. This is why tasting food for safety is not recommended.
The Foodsafety.gov website is a helpful resource for determining which frozen foods to keep or toss after a power outage. The following food should be tossed if the frozen food has been exposed to temperatures that have reached 40 degrees Fahrenheit or higher for more than two hours:
- Meat, poultry and seafood.
- Soups, stews and casseroles.
- Dairy and egg products.
- Cheese that is soft/semi-soft or shredded.
- Cake, pie and pastry items with custard or cheese fillings.
Keep in mind that perishable food such as meat, poultry, seafood, milk, and eggs that are not adequately frozen or refrigerated or may cause afoodborne illnessif consumed, even when thoroughly cooked.
What to do next
Clean and sanitize the freezer. If the freezer has to be defrosted first, refer to the manufacturer's directions. The Centers for Disease Control provides directions for cleaning and sanitizing due to recalled food. The same steps can be followed after a power outage. Stubborn odors can be tackled with directions from the USDA. Make sure the frozen food can be held at a temperature of 0 degrees Fahrenheit or lower during this time.
The cost and discomfort of a foodborne illness greatly outweigh tossing out perishable food, such as meat, poultry, fish, eggs, or leftovers that have been above 40 degrees Fahrenheit for two hours or more.
Planning ahead
The best way to minimize the amount of food waste and maximize the money spent on food is to be prepared for the next time there is a power outage. MSU Extension has recommendations to keep food safe in emergencies and keeping food safe during a power outage. Following these guidelines can help prevent foodborne illnesses after a power outage.
A final tip to remember is simply: When in doubt, throw it out.
For more information on food safety, visit
