Freezer or refrigerator failure can occur for various reasons. Winter storms, electrical line work or a child accidentally leaving the freeze door open can all have the same consequence.

Thawed food can mean a serious loss of money when there is a substantial amount of groceries stored in the freezer and refrigerator. Here are the basics on how to prepare your fridge and freezer if you anticipate a power outage.

• Use a thermometer. Make sure you have a thermometer inside your refrigerators and freezers. Determining the safety of thawed food will be much easier if you know the temperature of the unit. It is a good idea to set the freezer temperature control to minus 10 to minus 20 degrees Fahrenheit prior to the power going off. The colder your freezer is when the power goes off, the better your chances the food will remain safe.

• Fill it up. A full freezer stays safely frozen approximately two days; a half-full freezer for one day. Adding bags or jugs of ice is a good way to fill vacant freezer space. If your freezer is not full, quickly group similar packages together so their juices from thawing will not contaminate other products. Meats and poultry should be grouped on a low shelf (or on a separate tray) so that drips are limited.

• Leave the door closed. Once you’ve quickly arranged your foods in the refrigerator or freezer unit, close the unit door and leave it closed to trap in cold air.

When power has been restored, the looming question is always this: “Which foods can I keep and which should I throw away?”

The answer? Follow these guidelines.

• Ice crystals are good. If there are still ice crystals in the package of food, the food can safely be refrozen. This applies to any food in the freezer.

• No ice crystals? Proceed with great caution. When a perishable food has been stored in temperatures higher than 40 degrees longer than two hours, the chances for bacterial growth and food-borne illnesses increase.

• Meats: Examine each package individually. Discard any packages that are questionable due to odor or texture. Pay special attention to sliced, cubed and ground meats since these are particularly perishable. If you don’t know how long the freezer has been off and the meat is completely thawed and warm, throw it away.

• Leftovers, casseroles and frozen entrees: Discard all previously cooked foods once they have completely thawed.

• Fruits: Thawed fruit can be refrozen as long as there are no signs of mold, yeast or decay.

• Vegetables: Plain vegetables can be refrozen if they are still cold to the touch and show no signs of spoilage. Discard thawed vegetables held above 40 degrees for more than six hours due to the potential for spoilage.

Clip and save: What to keep, what to toss

Here’s a handy list of foods to save or discard after a power or freezer failure...

• Pickles and olives

• Mustard and any vinegar-based condiments

• Margarine and butter

• Hard cheese

• Fresh, whole fruits and vegetables

• Fruit juice

• Flour, nuts, jelly, barbecue sauce

• Bread, muffins, fruit pies, non-cream style cakes

• Food with ice crystals

• Thawed fruits showing no mold, yeast or decay

• Thawed vegetables still cold to the touch

• Meat, poultry, fish, eggs, lunch meats

• Milk, yogurt, soft cheese

• Casseroles, leftovers

• Custard or pudding

• Raw cookie or biscuit dough

• Cut leafy greens

• Cut melons and tomatoes

• Thawed meat warmer than 40 degrees for more than two hours

• Frozen entrees that have completely thawed

• Thawed fruits with a sour smell or signs of decay

• Thawed vegetables warmer than 40 degrees for more than six hours