Food must be kept at a safe temperature during defrosting. Foods are safe indefinitely while frozen; however, as soon as food begins to defrost and become warmer than 40°F, any bacteria that may have been present before freezing can begin to multiply. Never thaw food at room temperature or in warm water. Even though the center of a package may still be frozen as it thaws on the counter or in the warm water, the outer layer of the food is in the "Danger Zone," between 40 and 140°F. These are temperatures where bacteria multiply rapidly.
Thaw food in the refrigerator at 40°F or less, in cold running water less than 70°F, or in the microwave if you'll be cooking or serving it immediately.
Thawing in the refrigerator takes the longest time and advance planning. A large frozen item like a turkey requires at least a day (24 hours) for every 5 pounds of weight. Even small amounts of frozen food –- such as a pound of ground meat or boneless chicken breasts –- require a full day to thaw. When thawing foods in the refrigerator, there are several variables to take into account:
Thawing in cold water requires less time but more attention than thawing in the refrigerator. This should only be used if the water is kept cold (less than 70°F) and the food will thaw in under 2 hours. The food must be in a leak-proof package or plastic bag. If the bag leaks, bacteria from the air or surrounding environment could be introduced into the food. Also, meat tissue can also absorb water like a sponge, resulting in a watery product. As an alternative to constantly running water, the bag of food could be submerged in cold tap water, changing the water every 30 minutes as the food continues to thaw.
Thawing in the microwave oven produces some uneven heating patterns. Some parts of a food may actually start to cook before other sections completely thaw. Holding partially cooked food is not recommended because any bacteria present wouldn't have been destroyed and, indeed, may have reached optimal temperatures for bacteria to grow. Use the microwave when the food will be cooked immediately after thawing, or for thawing ready-to-eat fruits immediately before serving.
When serving frozen fruits for dessert, serve them while there are still a few ice crystals in the fruit. This helps compensate for the mushy texture frozen fruits have when thawed.
Frozen fruit in the package can be thawed in the refrigerator, under running water, or in a microwave oven if thawed immediately before use. Turn the package several times for more even thawing. Allow 6 to 8 hours in the refrigerator for thawing a 1 pound package of fruit packed in syrup. Allow ½ to 1 hour for thawing in running cool water.
Fruit packed with dry sugar thaws slightly faster than that packed in syrup. Both sugar and syrup packs thaw faster than unsweetened packs.
Thaw only as much as you need at one time. If you have leftover thawed fruit, it will keep better if you cook it. To cook, first thaw fruits until pieces can be loosened; then cook as you would cook fresh fruit. If there is not enough juice to prevent scorching, add water as needed.
When using frozen fruits in cooking, allowance should be made for any sugar that was added at the time of freezing. Frozen fruits often have more juice than called for in recipes for baked products using fresh fruits. In that case, use only part of the juice or add more thickening for the extra juice.
Suggested Uses for Frozen Fruits
Most frozen vegetables should be cooked without thawing first. Corn on the cob should be partially thawed before cooking in order for the cob to be heated through by the time the corn is cooked. Letting the corn sit after thawing or cooking causes sogginess. Leafy greens, such as turnip greens and spinach, cook more evenly if partially thawed before cooking.
To cook, bring water to a boil in a covered saucepan. The amount of water needed depends on the vegetable and the size of the package. It is important to use as little water as possible, because some nutrients dissolve into the water. For most vegetables, ½ cup of water is enough for a pint package. Any frost in the package furnishes some additional moisture.
Place the frozen vegetables in boiling water, cover the pan and bring the water quickly back to a boil. To insure uniform cooking, it may be necessary to separate pieces carefully with a fork. When the water is boiling throughout the pan, reduce the heat and cook until done. Be sure the pan is covered to keep in the steam, which aids in cooking. Cook gently until vegetables are just tender. Add seasonings as desired and serve immediately or use in casseroles.
Meat, Fish and Poultry – Meat, fish and poultry can be cooked from the frozen or thawed stage. Frozen meats, fish and poultry are best when thawed in the refrigerator in their original wrappings. For faster thawing, place the meat or fish in waterproof wrapping in cold, slowly running water. If you can’t keep water running slowly over the package, place in a large container of cold water. Change the water at least every 30 minutes, or as needed so that it stays cold. Frozen meat, fish or poultry can also be thawed in a microwave oven, if they will be cooked immediately after thawing.
If meat, fish or poultry is cooked without thawing, additional time must be allowed. How much depends on the size and shape of the product. Large frozen roasts could take up to 1½ times as long.
When frozen meat, fish or poultry are to be breaded and fried, they should be at least partially thawed in the refrigerator first, for easier handling. All poultry which is to be stuffed should be thawed completely for safety.
For best quality cook thawed meat or fish immediately.
Butter, Eggs, Milk and Cheese – Place the frozen product in the refrigerator to thaw. After thawing, it can be used as fresh.
Cream – Thaw the same as butter, but before using the thawed cream, it should be mixed or blended slightly.
Most cooked or prepared foods do not have to be thawed before heating. Food can be reheated in the oven to preserve its texture. Be careful not to put a cold glass container into a preheated oven, unless its manufacturer specifies that it is freezer to oven safe. For speedy reheating of products such as noodle casseroles, without excessive stirring, heat the food in a double boiler. Start with warm, not hot, water in the lower pan so the food will not stick. This prevents the casserole from becoming "mush". Cassseroles, soups, stews and leftovers should be heated to at least 165°F in the center prior to serving.
Products containing meat, fish, poultry, eggs or dairy products should be thawed in the refrigerator or in the microwave oven. These products could cause food poisoning if they stay at room temperature for more than 2 to 4 hours.
Precooked breads, cakes and cookies can be thawed at room temperature.
This document was adapted from "So Easy to Preserve", 5th ed. 2006. Bulletin 989, Cooperative Extension Service, The University of Georgia, Athens. Revised by Elizabeth L. Andress. Ph.D. and Judy A. Harrison, Ph.D., Extension Foods Specialists.