If the power is out for less than 2 hours, then the food in your refrigerator and freezer will be safe to consume. While the power is out, keep the refrigerator and freezer doors closed as much as possible to keep food cold for longer. • For the Freezer section: A freezer that is half full will hold food safely for up to 24 hours.
http://www.thekitchn.com/power-out-a-guide-to-refrigerator-safety-when-you-dont-have-electricity-173583
All your fruit is safe to keep unrefrigerated, unless it's already been cut. If that's the case, toss it. Many of your kitchen staples will last even through a power outage. Peanut butter, jelly, relish, mustard, ketchup and sauces like soy, barbecue and Worcestershire are all safe, as are any vinegar-based dressings.
http://www.huffingtonpost.ca/2013/12/23/food-power-outage-blackout_n_4492798.html
However, if you’ve lost power for more than four hours and the temperature in your refrigerator was above 40 degrees F for more than two hours you need to discard all perishable items, including: 1  Meat, poultry, seafood and eggs. 2  Milk, yogurt, soft cheeses such as bleu or mozzarella, shredded cheese and low-fat cheese.
https://www.leaf.tv/articles/how-long-does-food-keep-in-a-refrigerator-with-no-power/
Is food in the refrigerator safe during a power outage? It should be safe as long as power is out no more than 4 hours. Keep the door closed as much as possible. Discard any perishable food (such as meat, poultry, fish, eggs, and leftovers) that have been above 40 °F for over 2 hours. Never taste food to determine its safety!
https://www.foodsafety.gov/keep/charts/refridg_food.html
To help keep your refrigerator at the ideal temperature for the longest period of time during a power outage, keep the doors closed. If left unopened, the refrigerator can hold its temperature for up to four hours and the freezer for up to 48 hours. Tips. Invest in a refrigerator thermometer to help you monitor temperature during an outage.
https://www.leaf.tv/articles/how-long-does-food-keep-in-a-refrigerator-with-no-power/
Much of that depends on how long your power has been out, and how much you have inside your fridge or freezer. According to the Canadian Food Inspection Agency (CFIA), a full freezer will stay frozen for 48 hours, while a half-full freezer will keep its cool for 24.
http://www.huffingtonpost.ca/2013/12/23/food-power-outage-blackout_n_4492798.html
The USDA says to keep the refrigerator and freezer doors closed as much as possible to maintain the cold temperature.. But, the refrigerator will only keep food safely cold for about four hours if unopened during a power outage, according to the USDA. A full freezer will hold the temperature for about 48 hours if full (24 hours of half full), the USDA says.
https://patch.com/massachusetts/medfield/still-without-power-how-long-will-food-last-in-the-fridge
A refrigerator, meanwhile, will stay keep food cold for four hours, as long as it isn't opened. Some rules of thumb to keep in mind, via CFIA: Discard any thawed food that has been at room temperature for two or more hours, and any food that has an obvious unusual colour or odour.
http://www.huffingtonpost.ca/2013/12/23/food-power-outage-blackout_n_4492798.html
A full freezer helps keep food colder longer. If your freezer isn’t full, pack the foods tightly together to help hold temperature. While your refrigerator may be pretty empty after an outage, you don’t have to throw everything away. Foods safe to keep include: Peanut butter. Jelly and jam.
https://www.leaf.tv/articles/how-long-does-food-keep-in-a-refrigerator-with-no-power/
Generally, if the temperature in the thermometer in the freezer reads 40 degrees Fahrenheit or below, the food is safe and can be refrozen, according to the USDA. The USDA suggests obtaining dry or block ice to help keep refrigerated or frozen food cold if the power will be out for an extended period of time.
https://patch.com/massachusetts/medfield/still-without-power-how-long-will-food-last-in-the-fridge
how to keep fridge cold in power outage
To keep the fridge cold during a power outage, you need to keep the doors closed. Keep the doors closed of fridge to keep it cold in power outage.