What Can You Freeze?
You can freeze almost any food. Some exceptions are canned food or eggs in shells.
However, once the food (such as a ham) is out of the can, you may freeze it.
Being able to freeze food and being pleased with the quality after defrosting are
two different things. Some foods simply don't freeze well. Examples are mayonnaise, cream
sauce and lettuce. Raw meat and poultry maintain their quality longer than their cooked
counterparts because moisture is lost during cooking.
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Is Frozen Food Safe?
Food stored constantly at 0°F (17.7°C) will always be safe. Only the quality
suffers with lengthy freezer storage. Freezing keeps food safe by slowing the movement of
molecules, causing microbes to enter a dormant stage. Freezing preserves food for extended
periods because it prevents the growth of microorganisms that cause both food spoilage and
foodborne illness.
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Does Freezing Destroy Bacteria & Parasites?
Freezing to 0°F (17.7°C) inactivates any microbes - bacteria, yeasts and molds -
present in food. Once thawed, however, these microbes can again become active, multiplying
under the right conditions to levels that can lead to foodborne illness. Since they will
then grow at about the same rate as microorganisms on fresh food, you must handle thawed
items as you would any perishable food.
Trichina and other parasites can be destroyed by sub-zero freezing temperatures. However,
very strict government-supervised conditions must be met. It is not recommended to rely on
home freezing to destroy trichina. Thorough cooking will destroy all parasites.
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Freshness & Quality
Freshness and quality at the time of freezing affect the condition of frozen foods.
If frozen at peak quality, foods emerge tasting better than foods frozen near the end of
their useful life. So freeze items you won't use quickly sooner rather than later. Store
all foods at 0°F (17.7°C) or lower to retain vitamin content, color, flavor and
texture.
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Nutrient Retention
The freezing process itself does not destroy nutrients. In meat and poultry products,
there is little change in nutrient value during freezer storage.
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Enzymes
Enzyme activity can lead to the deterioration of food quality. Enzymes present in animals,
vegetables and fruit promote chemical reactions, such as ripening. Freezing only slows the
enzyme activity that takes place in foods. It does not halt these reactions which continue
after harvesting. Enzyme activity does not harm frozen meats or fish and is neutralized by
the acids in frozen fruits. But most vegetables that freeze well are low acid and require
a brief, partial cooking to prevent deterioration. This is called "blanching." For
successful freezing, blanch or partially cook vegetables in boiling water or in a
microwave oven. Then rapidly chill the vegetables prior to freezing and storage. Consult a
cookbook for timing.
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Packaging
Proper packaging helps maintain quality and prevent "freezer burn." It is safe to freeze
meat or poultry directly in its supermarket wrapping but this type of wrap is permeable to
air. Unless you will be using the food in a month or two, overwrap these packages as you
would any food for long-term storage using airtight heavy-duty foil, (freezer) plastic
wrap or freezer paper, or place the package inside a (freezer) plastic bag. Use these
materials or airtight freezer containers to repackage family packs into smaller amounts.
It is not necessary to rinse meat and poultry before freezing. Freeze unopened vacuum
packages as is. If you notice that a package has accidentally been torn or has opened
while food is in the freezer, the food is still safe to use; merely overwrap or rewrap it.
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Freezer Burn
Freezer burn does not make food unsafe, merely dry in spots. It appears as grayish-brown
leathery spots and is caused by air reaching the surface of the food. Cut freezer-burned
portions away either before or after cooking the food. Heavily freezer-burned foods may
have to be discarded for quality reasons.
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Color Changes
Color changes can occur in frozen foods. The bright red color of meat as purchased usually
turns dark or pale brown depending on its variety. This may be due to lack of oxygen,
freezer burn or abnormally long storage.
Freezing doesn't usually cause color changes in poultry. However, the bones and the meat
near them can become dark. Bone darkening results when pigment seeps through the porous
bones of young poultry into the surrounding tissues when the poultry meat is frozen and
thawed.
The dulling of color in frozen vegetables and cooked foods is usually the result of
excessive drying due to improper packaging or over-lengthy storage.
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Freeze Rapidly
Freeze food as fast as possible to maintain its quality. Rapid freezing prevents
undesirable large ice crystals from forming throughout the product because the molecules
don't have time to take their positions in the characteristic six-sided snowflake. Slow
freezing creates large, disruptive ice crystals. During thawing, they damage the cells and
dissolve emulsions. This causes meat to "drip"--lose juiciness. Emulsions such as
mayonnaise or cream will separate and appear curdled.
Ideally, a food 2-inches thick should freeze completely in about 2 hours. If your home
freezer has a "quick-freeze" shelf, use it. Never stack packages to be frozen. Instead,
spread them out in one layer on various shelves, stacking them only after frozen solid.
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Refrigerator - Freezers
If a refrigerator freezing compartment can't maintain zero degrees or if the door is
opened frequently, use it for short-term food storage. Eat those foods as soon as possible
for best quality. Use a free-standing freezer set at 0°F (17.7°C) or below for
long-term storage of frozen foods. Keep a thermometer in your freezing compartment or
freezer to check the temperature. This is important if you experience power-out or
mechanical problems.
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Length of Time
Because freezing keeps food safe almost indefinitely, recommended storage times are for
quality only. Refer to the freezer storage chart at the end of this document, which lists
optimum freezing times for best quality.
If a food is not listed on the chart, you may determine its quality after defrosting.
First check the odor. Some foods will develop a rancid or off odor when frozen too long
and should be discarded. Some may not look picture perfect or be of high enough quality to
serve alone but may be edible; use them to make soups or stews. Cook raw food and if you
like the taste and texture, use it.
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Safe Defrosting
Never defrost foods in a garage, basement, car, dishwasher or plastic garbage bag; out on
the kitchen counter, outdoors or on the porch. These methods can leave your foods unsafe
to eat.
There are three safe ways to defrost food: in the refrigerator, in cold water, or in the
microwave. It's best to plan ahead for slow, safe thawing in the refrigerator. Small items
may defrost overnight; most foods require a day or two. And large items like turkeys may
take longer, approximately one day for each 5 pounds of weight.
For faster defrosting, place food in a leak proof plastic bag and immerse it in cold
water. (If the bag leaks, bacteria from the air or surrounding environment could be
introduced into the food. Tissues can also absorb water like a sponge, resulting in a
watery product.) Check the water frequently to be sure it stays cold. Change the water
every 30 minutes. After thawing, cook immediately.
When microwave-defrosting food, plan to cook it immediately after thawing because some
areas of the food may become warm and begin to cook during microwaving.
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Refreezing
Once food is thawed in the refrigerator, it is safe to refreeze it without cooking,
although there may be a loss of quality due to the moisture lost through defrosting. After
cooking raw foods which were previously frozen, it is safe to freeze the cooked foods. If
previously cooked foods are thawed in the refrigerator, you may refreeze the unused
portion.
If you purchase previously frozen meat, poultry or fish at a retail store, you can
refreeze if it has been handled properly.
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Cooking Frozen Foods
Raw or cooked meat, poultry or casseroles can be cooked or reheated from the frozen state.
However, it will take approximately one and a half times the usual cooking time for food
which has been thawed. Remember to discard any wrapping or absorbent paper from meat or
poultry.
When cooking whole poultry, remove the giblet pack from the cavity as soon as you can
loosen it. Cook the giblets separately. Read the label on USDA-inspected frozen meat and
poultry products. Some, such as pre-stuffed whole birds, MUST be cooked from the frozen
state to ensure a safely cooked product.
LOOK FOR THE USDA OR STATE MARK OF INSPECTION
The inspection mark on the packaging tells you the product was prepared in a USDA or
State-inspected plant under controlled conditions. Follow the package directions for
thawing, reheating, and storing.
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Power Outage in Freezer
If there is a power outage, the freezer fails, or if the freezer door has been left ajar
by mistake, the food may still be safe to use. As long as a freezer with its door ajar is
continuing to cool, the foods should stay safe overnight. If a repairman is on the way or
it appears the power will be on soon, just don't open the freezer door.
A freezer full of food will usually keep about 2 days if the door is kept shut; a
half-full freezer will last about a day. The freezing compartment in a refrigerator may
not keep foods frozen as long. If the freezer is not full, quickly group packages together
so they will retain the cold more effectively. Separate meat and poultry items from other
foods so if they begin to thaw, their juices won't drip onto other foods.
When the power is off, you may want to put dry ice, block ice, or bags of ice in the
freezer or transfer foods to a friend's freezer until power is restored. Use an appliance
thermometer to monitor the temperature.
When it is freezing outside and there is snow on the ground, it seems like a good place to
keep food until the power comes on; however, frozen food can thaw if it is exposed to the
sun's rays even when the temperature is very cold. Refrigerated food may become too warm
and foodborne bacteria could grow. The outside temperature could vary hour by hour and the
temperature outside will not protect refrigerated and frozen food. Additionally,
perishable items could be exposed to unsanitary conditions or to animals. Animals may
harbor bacteria or disease; never consume food that has come in contact with an animal.
To determine the safety of foods when the power goes on, check their condition and
temperature. If food is partly frozen, still has ice crystals, or is as cold as if it were
in a refrigerator 40°F (4.4°C), it is safe to refreeze or use. It's not necessary
to cook raw foods before refreezing. Discard foods that have been warmer than 40°F
(4.4°C) for more than 2 hours. Discard any foods that have been contaminated by raw
meat juices. Dispose of soft or melted ice cream for quality's sake.
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Frozen Cans
Accidentally frozen cans, such as those left in a car or basement in sub-zero temperatures, can present health problems. If the cans are merely swollen - and you are sure the swelling was caused by freezing - the cans may still be usable. Let the can thaw in the refrigerator before opening. If the product doesn't look and/or smell normal, throw it out. DO NOT TASTE IT! If the seams have rusted or burst, throw the cans out immediately, wrapping the burst
can in plastic and disposing the food where no one, including animals can get it.
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Frozen Eggs
Shell eggs should not be frozen. If an egg accidentally freezes and the shell cracked
during freezing, discard the egg. Keep an uncracked egg frozen until needed; then thaw in
the refrigerator. It can be hard cooked successfully but other uses may be limited. That's
because freezing causes the yolk to become thick and syrupy so it will not flow like an
unfrozen yolk or blend very well with the egg white or other ingredients.
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Freezer Storage Chart (0 °F)
Note: Freezer storage is for quality only. Frozen foods remain safe indefinitely.
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Foods in the freezer - are they safe? Every year, thousands of callers to the USDA Meat
and Poultry Hotline aren't sure about the safety of items stored in their own home
freezers.
