Freezing to Preserve Food

Five Things You Can Do Now

1. Purchase a freezer if you don’t already own one.
2. Defrost and organize your freezer.
3. Purchase berries or other produce on sale, flash freeze it, and then store in containers in your freezer.
4. Set the freezer thermostat at zero degrees or below, especially if you anticipate power outages.
5. Keep your freezer full. If necessary, fill clean milk jugs with water, freeze, and then use to maintain temperature in a full freezer.

Despite the high quality of most frozen foods, you should not rely on freezing as your main method of preservation. Its primary drawback is its susceptibility to power failure. You will find recommendations later in the chapter about what to do if this happens. It is also expensive when compared with other food-preservation methods.

The Basics of Freezing Food

The Pros and Cons

Freezing is an excellent and easy way to preserve many fruits, vegetables, and meats. However, because of the ongoing energy requirements, it is expensive when compared with canning and dehydrating. Because of its vulnerability, during a prolonged power outage, you would need an alternate power source to keep the freezer running or the means for preserving the food that defrosts. Another risk to freezers is that they can malfunction, putting your frozen food at risk at any time.

Equipment for Freezing Food

Table 30.1 Freezing Equipment and Supplies
Ascorbic acid 6- to 8-quart pan for blanching Colander Cooler or ice chest Freezer containers, assorted Freezer wrap and tape	Funnel, wide-mouth Heavy-duty resealable bags Tongs Vacuum bags Vacuum sealer Wire basket for scalding

Of course, to freeze food you need a freezer. A chest freezer is better at retaining cold when opened. Look for one with sliding baskets that help you organize. Also use small removable tubs to organize smaller items. A lock will prevent accidental opening and theft. Plan on about six cubic feet per person.

A cooler or ice chest is useful during a power outage. Items stay frozen longer if they are tightly packed. Coolers also allow for portability of frozen items.

Vacuum Sealing Food for Freezing

Table 30.2 Approximate Yield from Fresh Fruits
Fruit	Fresh Quantity	Frozen Quantity in Pints
Apples	1 bushel (48 lb.)	32—40
Apricots	1 lug or crate (22 lb.)	10—12
Berries	1 crate (24 qt.)	32—36
Cantaloupe	1 dozen (28 lb.)	20—24
Cherries	1 lug (25 lb.)	8—10
Cranberries	1 box (25 lb.)	46—54
Peaches	1 half bushel (24 lb.)	16—24
Pears	1 bushel (50 lb.)	40—50
Pineapple	5 lb.	3—5
Plums	1 bushel (56 lb.)	38—56
Strawberries	1 crate (24 qt.)	36—40

Proper wrapping prevents freezer burn. The ideal method is to use a vacuum sealer. Food Saver makes a line of vacuum sealing systems (pictured) that work well for meats and many fruits and vegetables. It can be a challenge to use if the item has excess liquid because the vacuum sucks the liquid and prevents a seal from forming. You will need a supply of bags in various sizes to go with the sealer. Table 30.1 lists the equipment and supplies needed for packaging frozen foods.

Ascorbic acid is used as an anti-oxidant and to prevent discoloration of fruits. Use sugar to wet-pack fruits for added flavor.

Flash Freezing

Flash freezing prevents the formation of large ice crystals that rupture cells and harm texture and flavor. It works best if your freezer is set at -20° F (-29° C) or below. Place a single layer of produce or pieces of meat on a precooled tray, then place the tray in the coldest part of the freezer for twenty-four hours. Repackage the frozen items in a vacuum-sealed bag or other container.

Table 30.3 Approximate Yield from Fresh Vegetables
Vegetable	Fresh Quantity	Frozen Quantity in Pints
Asparagus	1 crate (30 lbs)	15-22
Beans	1 bushel (30 lbs)	30-45
Beets	1 bushel (52 lbs)	35-42
Broccoli	1 crate (25 lbs)	22-26
Carrots	1 bushel (50 lbs)	32-40
Corn	1 bushel (35 lbs)	14-17
Peas	1 bushel (30 lbs)	12-15
Peppers	3 peppers	1
Tomatoes	1 bushel (53 lbs)	15-20

Freezer Backup

One way around part of the vulnerability of frozen food is to have an alternative energy source so that outages and shortages will not affect you as much. If you live where you are frequently affected by power outages, a backup generator is a good idea. Small portable generators are another option. Refrigerators and freezers that run on propane or kerosene can also be used as a backup to your regular freezer. And, of course, you’ll need to store fuel for the generator or for the alternative refrigerators and freezers mentioned. (See chapter 36)

Quantities of Frozen Food

Meats and seafood freeze well, especially if vacuum-sealed. Many kinds of produce also freeze well, including applesauce, asparagus, berries, green beans, lima beans, broccoli, carrots, cauliflower, corn, peas, peaches, peppers, potatoes, and spinach.

Use tables 30.2 and 30.3 to help you determine how much fresh fruit and vegetables are needed to produce a specific yield. The actual number of pints will depend on the variety, size, maturity, and quality of the produce. It will especially depend on the way the food is prepared.

Personally Speaking

Freezer space is kind of like real estate. Not all things that can go in the freezer are of equal value, and they do not get the same amount of freezer “real estate.” I carefully consider what gets space in the freezer. They are usually expensive, convenient, or rare.

Seafood, meat, and nuts get priority because they are more expensive than other items and the cost to replace them if they spoil is greater. The peppers we have at the end of the summer get space because they are convenient. We slice them and seal them in vacuum-packed bags for fajitas and stir-fry. Since we like our fresh frozen corn much better than any store-bought varieties, it gets a fair amount of space because it is rare—we can only get it when we harvest our garden. The same goes for our frozen pesto sauce made from the basil we grow.

I recommend you use freezer space economically and prepare produce so that it takes up the least amount of space. Since I make jam from peaches, apricots, and berries, I puree them in jam-sized batches, label them, and freeze them. They take up less space than whole or sliced fruit and are ready go when I want to make fresh jam.

I also like to use the freezer to take advantage of grocery-store sales. I have learned that butter freezes well and is usually cheapest right before the fall holidays when grocery stores are trying to get your business. So that is when we stock up and keep it in our freezer to use all year. When chicken breasts go on sale in bulk, we buy a package or two and vacuum pack individual breasts to freeze and use later.

One of my favorite conveniences is to keep nuts and seeds in the freezer. Again, I buy them in bulk and keep them secure in their own bag inside a second, resealable bag. I dedicate a storage basket to all nuts and seeds so they are easy to find when we need them. Freezing nuts keeps them from becoming rancid. It also keeps out annoying pests. Though I have kept nuts in the freezer for at least two years, they are usually eaten long before that.

Lastly, I use the freezer to make life easier. I like to cook in big batches, so if there is room in the freezer, I make batches of cooked beans, specialty sauces, soups, and baked dishes and freeze them in meal-size containers, then thaw them when we need a quick meal.

All the things in our freezer are a comforting part of our short-term food storage. We realize that a prolonged power outage would have us scrambling to take care of the thawing food, but we are willing to live with that risk.

Remember, in an extended power outage, you’ll have a few days to preserve the food using another method.

Shelf Life of Frozen Foods

Table 30.4 Storage Life for Frozen Foods
Meat	Months		Vegetables	Months
Ground beef	2—3 months		Asparagus	6—8 months
Stew meat	2—3 months		Beans	8—12 months
Beef roasts	8—12 months		Beets	12 months
Fish, fat varieties	2—3 months		Broccoli	12 months
Fish, lean varieties	6—9 months		Brussels sprouts	8—12 months
Lamb chops	3—4 months		Carrots	12 months
Lamb, ground	2—3 months		Cauliflower	12 months
Lamb, roasts	8—12 months		Corn	8—12 months
Pork chops	3—4 months		Okra	12 months
Ham and sausage	1—2 months		Peas	12 months
Pork roasts	3—8 months		Peppers	8—12 months
Organ meats	3—4 months		Pumpkin	12 months
Miscellaneous	Months		Winter squash	12 months
Baked goods	2—3 months		Spinach and greens	12 months
Butter and lard	6—8 month		Fruits	Months
Cheese	6—8 months		Citrus fruits and juices	4—6 months
Coconut, shredded	8—12 months		Mixed fruit	6—8 months
Cookies	8—12 months		Other fruits	12 months
Cream	3—4 months		Berries	12 months
Eggs (not in shell)	8—12 months		Nuts	6—12 months

The biggest risk to frozen foods is the freezer burn caused by dehydration and oxidation. It occurs over time when frozen food is exposed to air. You can lessen this with proper packaging. A vacuum sealer will give you the highest quality frozen goods. Repackage items like fish fillets and frozen shrimp in vacuum packages.

Freeze purees and soups in plastic containers with a layer of plastic wrap securely fitted on top of the liquid.

The other factor in shelf life is temperature. The best temperature is 0° F (-18° C) or lower. Although food kept at or below this temperature will store indefinitely and can be safely eaten, the quality will decline over time. Table 30.4 lists the optimal storage life at 0° F (-18° C) or below. Practically speaking, you may be able to store frozen foods longer.

What to Do with the Freezer in a Power Outage

If your freezer loses power for whatever reason, there are things you can do to protect or salvage your food. In warm weather, you’ll have to act fast. In cooler weather, you’ll have a few days to solve the problem.

Protecting the Food in a Nonworking Freezer

During a power outage it is best not to open the freezer at all.

First, only open the freezer if it’s absolutely necessary. If possible, do not open it at all. Even a nonworking freezer will keep food frozen for some time. How long it will keep food depends on how full it is, the types of foods, the size of the food packages—bigger is better—and the temperature of the room where the freezer is located. A fully stocked freezer can keep temperatures at satisfactory levels for two to three days providing it is kept closed. A partially filled freezer may keep food frozen only half as long. Conserve the cold by insulating the freezer with blankets and newspapers.

Using Dry Ice to Keep Things Frozen

If you can get it, dry ice will extend the time you can keep food frozen. A twenty-five to fifty-pound block will keep the temperature of a half-full freezer below freezing for two to three days. Put the food close together and then, using tongs or gloves, place the dry ice on a layer of heavy cardboard over the center of the food. A large block of dry ice will last longer than several small ones.

Because dry ice evaporates and produces tremendous amounts of carbon dioxide, the area should be ventilated and the freezer door left slightly ajar to prevent a dangerous buildup of pressure.

Anticipated Power Outages

If you are anticipating a power outage, transfer the foods you’ll use right away to a quality camping cooler with ice. You may also want to prepare gallon jugs of ice to place in the freezer to fill the air space and help keep it cold. With advanced warning or if you are subject to frequent power failures, set the freezer temperature to its lowest setting. The colder the temperature inside the freezer when the outage begins, the longer the food will stay frozen.

You may be interested in a power failure alarm to alert you whenever the power goes off. Should your freezer be inoperable beyond these measures, you can take the frozen food to a commercial locker, assuming the outage has not affected them, or immediately preserve the food by canning, dehydrating, or smoking it.

When to Refreeze

As a rule, if a food is safe to eat, it is safe to refreeze. In practice, with most foods, that means they have not thawed completely and are still under 40° F (5° C). How can you tell? Some ice crystals will still be present. Their existence means the food is between 32° F and 40° F and can be refrozen. Exceptions to this are deli meats, fish, and other seafood that spoil very quickly. Expect refrozen foods to have a lower quality and to not keep as long. They should be used as soon as possible.

If foods have completely thawed, do not refreeze, and use at once. Uncooked vegetables, meats, and poultry can be cooked and then refrozen. Fruits can be canned or made into preserves. Fruit-juice concentrates ferment when spoiled and can cause the cans to explode. Throw out any off-flavor fruits.