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CHAPTER 3

Freezing: Flexible Food Preservation

Now that we have all of the background behind us, we’re ready to start putting away some food. Because the goal of this book is to keep things simple, we’re going to start with freezing, which is far and away the easiest and most flexible method of food preservation. Here is a short list of the advantages of freezing (one of which is that you can freeze apple rings for future pies):

Freezing is the ideal first step for beginners.

It’s quicker, easier, and requires less preparation than canning.

Food will taste better and have a better consistency than it would with most other types of food preservation.

Generally, more nutrients are preserved with freezing.

Food safety is less of an issue; there are no worries about botulism growing in a closed jar.

It works well with a range of food: fruits and vegetables, meats and seafoods, breads and pastries, and entire meals.

Almost anyone with a refrigerator/freezer and ordinary food-preparation and storage utensils can freeze food.

Freezer meals are ideal for busy families—and not-so-busy families—and for folks on special diets who will want to stock up on their specialized dishes.

You can easily control portion size because of the variety of storage options.

WHAT CAN YOU FREEZE?

The short, easy answer to that question is, “just about anything.” Unlike other methods of food preservation, freezing doesn’t depend upon eliminating or killing spoiling agents such as bacteria. If a particular food was safe to eat when you froze it and—this is very important—you keep it frozen at a steady 0 degrees Fahrenheit, it will be safe almost indefinitely. Of course, while the foods may be safe to eat, you may not want to eat them. Simply stated, some foods don’t freeze well and should either only be eaten fresh or be preserved in other ways. See the sidebar “Don’t Freeze These” for the short list of foods that don’t freeze well. The long list of foods that do freeze well includes the following:

Fruits

Vegetables

Meats and seafood

Breads and pastries

Meals

Jams and jellies specifically formulated for freezing

Almost any food stuff for which you want to extend the shelf life. For example, when your favorite orange juice is on sale, stock up and stick the half-gallons in the freezer.

We’ll go into specific how-tos for each major type of food category. But first, let’s look at some general guidelines and guidance.

Berries are one of the most versatile types of produce that you can freeze. Use them for pies, jellies, jams, dessert toppings, or simply as a cool snack on hot summer nights.

DON’T FREEZE THESE

Some foods don’t do all that well when frozen. The list is subject to personal preference, but here are the foods I (and many others) believe become unappetizing when frozen:

Salad greens and crisp raw vegetables will wilt and get soggy.

Eggs in the shell will expand and crack; cooked egg whites get tough and rubbery; and meringues and icings made from egg whites get tough and weepy. The exception among eggs is the separated egg white, which does fare well.

Soft dairy products (cottage cheese, whipping cream, and sour cream) and foods made from dairy, such as custard or milk sauces, will separate and become watery. Milk, however, can be successfully frozen. Just shake well after defrosting.

Potatoes, when frozen raw, become mushy; when cooked or mashed, they get waterlogged and mealy.

Pastas, when frozen alone for later use, get mushy and taste stale. Frozen pasta dishes, such as lasagna or macaroni and cheese, freeze reasonably well.

Sandwiches generally don’t freeze well. Some may differ, but I won’t waste my time making and freezing most sandwiches only to have them become soggy.

Except for French fries and fried onion rings, fried foods lose their crispness and get soggy.

Salt loses its flavor in prepared meals.

Hot and bell peppers, cloves, and artificial vanilla become strong and sometimes bitter in prepared meals.

GENERAL GUIDELINES

While in most cases freezing is as simple as putting your product into a freezer-safe container, here are some general guidelines:

Use freshly picked, unblemished, fully ripe produce. The freezer is no place for second-rate, albeit bargain, products.

Most vegetables must be blanched to stop enzyme action. See “All About Blanching” in the appendix for details and individual recipes for appropriate blanching times. Exceptions include vegetables used exclusively for flavoring, such as onions, peppers, and horseradish.

Fruits do not need to be blanched, but light fruits should be treated to prevent darkening. See “Treating for Discoloration” in the appendix for details.

Some enzymatic processes that are harmful to flavor and nutrition need to be blanched out of vegetables before they can be frozen.

Choose a freezer container suitable to the the product being frozen:

• Fruits in syrup, stews, and any food that is liquid at room temperature must be packed in a rigid container with sufficient space for expansion.

• Pack vegetables in moisture- and vapor-resistant freezer containers such as freezer bags or rigid containers.

• Wrap meats as tightly as possible in freezer wrap or butcher’s paper, and secure the wrapping with freezer tape.

• Frozen meals can be put in any appropriate freezer-safe container, as long as you take care to remove excess air and seal the container completely.

Label all containers—yes, including the see-through ones, even though you know you will remember what’s in there—with the contents, amount, and “date in” and “use by” dates (for example, “1 pint green beans, sealed August 15, 2012, use by August 15, 2013”).

Keep an inventory of all of the food in your freezer (see the appendix for a sample). Include the item, size, date in, and date to use by, and post this on your freezer door. Unless you have a photographic memory, it’s very easy to forget exactly what’s in your bounty chest. It can be as simple as a hand-written piece of paper or as elaborate as a color-coded spreadsheet, but as long as you can track your consumption, you won’t be caught empty-handed when that blueberry pie you were sure was in the freezer isn’t available for a last-minute dinner party. (Be prepared to suffer a bit of teasing by folks who may find this a bit obsessive!)

Check the freezer regularly to be sure that it’s running and that the temperature is set at 0 degrees Fahrenheit. (Better safe than sorry and surrounded by spoiled food!)

Twenty-four hours before freezing large amounts of food, set the thermostat back to -10 degrees Fahrenheit. This will help ensure that the new food freezes rapidly, preserving color, texture, and flavor, and helping to prevent spoilage in the case of meats and prepared meals. Once new foods are frozen, return the freezer thermostat to 0 degrees Fahrenheit.

Cool any hot foods as quickly as possible before freezing—avoid putting hot dishes directly in the freezer. For example, after blanching vegetables, immerse them in ice water. For prepared meals, remove them from the stove and put them in a cool, clean place. I use my breezeway during the winter; we call it our “EcoFridge.”

Leave a little space between packages when first putting them into the freezer to allow freezing air to circulate around them. Once they freeze, push them closely together to promote freezer efficiency.

Add only two to three pounds of new food for each cubic foot of freezer capacity to avoid creating unnecessary strain on the freezer motor or raising the freezer temperature.

When ready to use a food, thaw it carefully using only safe thawing methods (see the sidebar below).

Thaw Safely!

Freezing is a very safe form of food preservation because the microorganisms that cause food spoilage and food-borne illness do not grow at freezing temperatures. However, these organisms are only put into a state of suspended animation! When the food is thawed, the organisms wake from their deep-frozen sleep and multiply. If not thawed properly, frozen food can be extremely dangerous; this is especially true for low-acid foods, vegetables, shellfish, and precooked dishes.

According to the US Department of Agriculture, there are three safe ways to thaw; the best is to thaw in the refrigerator. This requires planning ahead, yes, but it has more advantages than just food safety (though food safety is the best advantage!). You also save energy when you thaw in the refrigerator. The energy that was used to freeze the product is not wasted but is actually reused in your refrigerator. That is, your frozen pound of hamburger that sits in your refrigerator overnight to thaw is helping to keep your refrigerator cool, thus your refrigerator doesn’t have to work so hard and uses less energy. If you put that pound of hamburger on the counter to thaw, not only are you potentially creating a safe haven for dangerous microorganisms to breed, but you are also wasting all that cold energy. In addition, foods that are thawed in the refrigerator—especially those high in water content—tend to be less mushy.

Cold-water and microwave thawing are also safe. Cold-water thawing involves, as you might guess, submerging the food in cold water. But this is more involved than it sounds. The food must be in a leak-proof package. If you get water in the food, you have two potential problems: The first is introducing bacteria into the food and therefore creating the possibility of food-borne illness. The second is water-logging the food. This may not make the food unsafe, but it will likely make it less appetizing.

To thaw food in your microwave, use the defrost setting on your microwave to safely and quickly defrost your food. Make sure you eat or cook the food immediately. Never hold partially cooked or defrosted food for any length of time. The bacteria that were present when you froze the food now have an optimal environment to grow. Because of this, never refreeze thawed food without fully cooking it to kill the bacteria.

EQUIPMENT

Except for perhaps a separate freezer, there are few things you’ll need to purchase to start freezing food. Here are the basics:

Freezer: chest, upright, or the freezer that’s part of your refrigerator (see the next section “Freezers and Freezer Facts” that starts on page 41).

Two or three large pots (at least 6- to 8-quart capacity, preferably stainless on the inside), one with a steamer insert or basket. Use these for blanching, washing, rinsing, and cooling. Do not use galvanized, copper, or iron pots because acid reacts to these metals.

An assortment of bowls ranging in size from very large (more than 6 quarts) to small (1 quart) for mixing and staging

Desired freezer containers (see “Freezer Containers” on page 44)

Freezer or masking tape and permanent markers

Large colander

Cutting board

Paring knife

Pot holders (oven mitts)

Towels, ideally absorbent cloth ones

Clock or timer

THE SKINNY ON FREEZER TIME

Opinions differ about how long to store various frozen foods. In short, the less a food is processed (ground up, cooked, or seasoned), the longer it will keep in the freezer. Here’s a general rule of thumb regarding storage times:

Most fresh fruits and vegetables, fruit juices, and fruit jams and jellies: one year

Fresh cuts of meat such as steaks, chops, and roasts (not ground) including those from beef, lamb, veal, venison, chicken, and turkey: one year

Fresh pork (not ground): six to eight months

Ground meats, sausages, and organ meats: three to four months

Fish and shellfish: three months

Cured meats (bacon, cold cuts, sausages): one month. These have a substantially shorter freezer life, because the salt reduces the freezing temperature, which can cause meat to go rancid.

Prepared main dishes: one to four months

Bread and pastries: less than six months

Milk, ice cream, and soft cheeses: one to two months

Butter and hard cheeses: six months

Note: After these suggested storage times, the frozen food won’t be unsafe to eat (as long as it’s been stored at the proper temperature); it just won’t be very tasty or nutritious any longer.

FREEZERS AND FREEZER FACTS

When choosing and using your freezer, there are a few things to consider:

Type of freezer (chest, upright, freezer/refrigerator). Uprights are most popular because they make it easy to see and reach all of your food. Chest freezers allow you to store more food because you can stack packages without the risk of them falling out, and they tend to be more efficient because the cold air doesn’t escape as easily as it does from an upright. The freezer compartment of your refrigerator is convenient, but it is generally small and often won’t keep foods as cold as a stand-alone freezer.

Size of freezer (3 cubic feet up to 25 cubic feet). Choose the largest size that you think you will keep full. (Full freezers run more efficiently than partially full ones.) Fifteen cubic feet is good for an average family of four.

Frost-free or manual defrost. Frost-free freezers are more convenient, but they cost more to buy and to run and can remove moisture from frozen food. Conversely, manual-defrost freezers cost less initially and are cheaper to run. Yes, you must defrost them (usually about once a year), but if you do it when the freezer is close to empty, it’s not such a burdensome task—and it’s a good chance to find some forgotten food treasures!

Placement. Freezers work best in cool, dry areas such as basements and garages.

Safety (thermometers and locks). If your freezer doesn’t have a built-in thermometer, buy one at your local hardware store and check the temperature periodically to make sure your food is at a temperature no warmer than 0 degrees Fahrenheit. Locking your freezer is always a good idea, but it’s a must if you have little ones around.

Because a freezer is a big investment, you might find it helpful to search the Web for some brand comparisons and recommendations.

If you have row after row of healthy fruits and vegetables in your backyard garden, and you plan to freeze them all, you’ll need a stand-alone freezer.

RED ALERT! FREEZER OR POWER FAILURE

One major concern with freezing food is the potential for freezer failure because of malfunction, power outage, or simply forgetting to close the door (it happens). This is a distressing thought—especially if your freezer is full, like it should be—but take heart; in most cases, the situation’s not as bad as you think. Just remember a few things: If the door has been left open, as long as the freezer continues to produce cool air, foods should be safe overnight. A full freezer should keep foods safely frozen for about two days, sometimes longer. Half full = half as long. Chest freezers stay cold longer than uprights. The freezer compartment in your refrigerator won’t stay cold as long as a dedicated freezer will.

You can also take certain precautions to prevent food loss. If you are unsure of how long your freezer will be out, take one or more of the following actions, bearing in mind that you want to keep the door closed as much as possible:

Add dry ice. A fifty-pound block of dry ice can keep an average full freezer at a safe temperature for three to four days. If the freezer is half full or less, that time will be reduced to two to three days. If you can’t find dry ice, bagged ice is an alternative—although a less-effective one—that may keep foods safe for a day or so.

If your freezer is not full, group packages together so that they retain the cold better (the same as huddling for warmth).

Separate meats and poultry from other foods so that, if they do thaw, they don’t contaminate other packages with their dripping juices.

Ask neighbors if they have some room to spare in their freezers. If they do, pack up your wares in a cooler with ice and transport them.

Once your freezer is working again, check the freezer temperature and the temperature and condition of the food. According to the USDA, the food will be safe to eat (and can be safely refrozen) as long as it is partly frozen (still has some ice crystals) and is no warmer than 40 degrees Fahrenheit—the average temperature in your refrigerator. Unless your freezer was not working for a long time before you discovered the outage—one of the reasons for checking the temperature on a regular basis—you will probably be able to salvage most, if not all, of its contents. However, you must throw out any food that has been warmer than 40 degrees Fahrenheit for more than two hours or any food that has been touched by raw-meat fluids.

FREEZER CONTAINERS

Many years ago, when the kids were young and I wanted to try to earn a few extra coins but couldn’t work days (they didn’t have telecommuting back then), I sold products for a well-known plastic-container company. The gig didn’t last long, but I ended up with a ton of sturdy, square freezer containers, which I would never have been able to afford. That was more than three decades ago, and I still have many of them today. The point? It’s worth the investment to get good containers in which to store your frozen foods. While you can freeze in just about anything—plastic bags and wrap, foil, old margarine containers, carry-out containers, even the foam tray that the food was packaged in—the food will not fare as well during storage and will be less appealing when you use it. Here are some of the features you’ll want to look for in your containers:

Sturdy. Look for something that will last and hold up to repeated washings in your dishwasher without warping. Cheaper plastics will warp and crack.

Moisture- and vapor-proof. Containers should “lock out air and lock in freshness.” Sounds like a commercial, but it’s true. If your containers aren’t sealed well, you risk loss of moisture, which leads to freezer burn or ice-crystal formation.

Free from Bisphenol A (BPA). While there’s a fair amount of controversy about how safe BPA is in food storage containers, I’d stay clear of it until it’s resolved. Several government agencies have issued studies and warnings about its safety.

Stackable and shaped suitable to the product that you’re freezing. Square and rectangular containers are the most versatile, but other shapes can come in handy for specific uses.

Standard and convenient sizes. Look for freezer containers that are sized in volumes you tend to cook with (8 ounces, 16 ounces, 1 quart, 1 gallon).

Straight and wide. Avoid any containers—especially glass ones—that have narrow necks at the top. If you misjudge the amount of headspace you leave, you risk cracking the container. If you want to use glass containers, stick with those that were designed to go into the freezer and have straight necks (though not recycled mayonnaise and pickle jars).

These freezer containers are especially good because they are clear, have tightly locking lids, and can be easily stacked.

Allow Sufficient Headspace

Headspace is the distance between the lid of the container and the top of the food. When liquids freeze, they expand. So for foods that have high water content, you’ll need to anticipate this expansion. It won’t matter as much with dry-packed fruits and vegetables, but for soups, stews, juices, and fruits packed with syrup or other liquids, headspace is important. If you don’t allow sufficient space, the frozen food will pop the top off of your container. Be especially careful with soups, stews, and juices and avoid narrow-topped containers. Only use containers with tops the same width or wider than their bottoms. Foods with high water content will expand more when they freeze than those with low water content. If you put them in a narrow-topped container, they may break the container as they freeze and expand.

Use these general guidelines for headspace:

Dry-packed fruits and vegetables: allow a ½-inch headspace for all containers

Liquid-packed fruits and vegetables, soups, stews, juices, and so on: allow a ½-inch headspace for pints and 1 inch for quarts with wide openings. For containers with narrower openings (such as standard canning jars), leave ¾ inch for pints and 1½ inches for quarts.

This illustration shows the kind of jar you’ll use for water-bath and pressure canning, but the same principles apply to freezer containers. Keep this image in mind as you read about headspace in chapters 4 through 6.

PROCESS OVERVIEW

We’ll go into specific differences between freezing fruits and vegetables in a bit, but the process is similar enough that it’s worth giving you the step-by-step just once.

1. Get your produce (either picked or purchased). Look for varieties that are known to freeze well. Make sure whatever you choose is fully ripe and in great condition. If necessary, let it ripen for a few days until it’s at its flavor peak.

2. If you can’t freeze your produce immediately, refrigerate it.

3. Prepare your workspace. An important part of that preparation is making sure that everything is as clean as you can make it. Keep in mind that freezing doesn’t kill bacteria; it just keeps them from growing.

4. For fruits only: Decide whether to dry-pack them, wet-pack them with sugar, or syrup-pack them. (I’ll explain this in a bit.) This will influence the type of freezer container that you will use. All types of freezer containers are suitable for dry packing, but syrup packing works best with rigid containers—preferably ones with straight sides (not tapered) and screw-on tops.

5. For fruits only: if syrup-packing, make your syrup and let it cool (see page 50).

6. Gather and thoroughly clean all equipment and utensils.

7. Work in small quantities—just a few freezer containers at a time—to ensure the highest quality.

8. Examine and wash your produce carefully, changing the water frequently. Prepare the produce as described in the sections to follow (remove stems, seeds, and pits, and cut as desired).

9. Treat your produce to prevent darkening, if necessary. Generally, this is only for light-colored fruits such as apples, peaches, apricots, nectarines, pears, and bananas. See “Treating for Discoloration” in the appendix.

10. Blanch all vegetables as well as the fruits that you want to soften or remove skin from. (See “All About Blanching” in the appendix.)

11. Pack the produce according to instructions, leaving sufficient headspace if packing with liquid. (See “Allowing Sufficient Headspace” on page 45.)

12. Label the container with the contents and date, and update your freezer inventory.

13. Put your preserves in the freezer at -10 degrees Fahrenheit. Once the food is solidly frozen, return the freezer to 0 degrees Fahrenheit.

14. Enjoy within the next year!

THE TROUBLEMAKERS

The goal of freezing—or any type of food preservation—is to make the food not only safe but also tasty. There are a number of issues that can impair the quality of your frozen foods.

Enzymes. Enzymes are a harmless and necessary part of life—you’ll remember from earlier chapters that enzymes are chemicals found in all living organisms that control their change and growth. Unfortunately, after the product is picked, those enzymes don’t understand that their job is done. They just keep working, and the changes that they inflict may not be appetizing. This can be especially noticeable in frozen foods if they have not been properly prepared. Vegetables may become tougher and more fibrous; fruits will brown and lose vitamin C. To stop the enzyme activity, simply blanch your fruits and vegetables according to the instructions in “All About Blanching” in the appendix and following the times listed in each recipe.

Freezer Burn. Freezer burn is not a burn, but rather a loss of moisture. The dry climate inside the freezer literally saps the moisture out of frozen foods that are not sealed properly. The result depends upon the frozen product. Fruits, vegetables, breads, and meals will be dry and shriveled, often with a coating of ice crystals on the inside of the lid. Meats will take on a gray or whitish cast. In either case, the result, while not harmful, is not very appetizing and often causes loss of nutrients. Freezer burn is more likely to occur in frost-free freezers, which have fans that remove the moisture to prevent frost. This is highly preventable with the use of proper containers and wrapping methods.

Discoloration and oxidative changes. Light-colored fruits (such as peaches, pears, apples, apricots, and bananas) begin to darken when exposed to the air. While this does not affect the safety of the food, it does make it less appetizing and less nutritious. Pretreat these to retard darkening by following the instructions in “Treating for Discoloration” in the appendix.

Mushy texture. To ensure the best frozen product, remember to flash-freeze food at -10 degrees Fahrenheit and defrost it slowly at cool temperatures, ideally in your refrigerator.

FREEZING FRUITS

The method for freezing fruits is basically the same as described in “The Process Overview” on page 46. What changes is how you pack it, how much sugar you use, whether or not it needs to be treated to prevent darkening, and how much headspace you need to leave. With frozen fruit, the amount of sugar recommended is just that—a recommendation. Unlike with other types of food preservation, the safety of the fruit is not dependent upon the amount of sugar. The recipes give you recommended amounts.

PACKING THE FRUIT

You can always pack fruit dry without sugar, but many people prefer the texture and flavor of fruit that has been packed in sugar or sugar syrup. See “Sugar Syrups” on page 50 for syrup proportions.

Cookie-Sheet Quick-Freeze (CSQF) Method

To freeze flexible bulk supplies, first freeze the fruit, vegetable, or single meat portions on a large, flat sheet, such as a cookie sheet, lined with waxed or parchment paper at -10 degrees Fahrenheit. For fruits or vegetables, rinse them thoroughly, drain them, and spread them out into a single layer (for most vegetables, make sure you blanch and cool them first). For meats, pastries, breads, and so on, place single portions on the cookie sheet. Once the food is frozen, remove the cookie sheet from the freezer and quickly transfer the food to a freezer bag, making sure to break apart the frozen pieces, remove excess air, and seal the bag. (You can use rigid freezer containers, as well, but plastic zipper-style freezer bags are especially handy because they allow you to exhaust all air from inside, thus preventing freezer burn.) Any time you need some of your frozen food, simply unzip the bag, and remove only what you need—just enough blueberries for breakfast, just two chicken breasts for supper…you get the idea. Very convenient!

DRY PACKING

Dry packing is just that. After you wash and drain the fruit, treat it to prevent darkening if necessary, then put it in the container and freeze. For some fruits, such as blueberries and strawberries, the CSQF method works well (see the sidebar on page 48).

WET PACKING

For wet packing, you pack the fruit with some type of liquid, such as its own juices, sugar or honey syrup, fruit juice, crushed fruit, or water. Rigid freezer containers work best for wet-packed fruits. When packing the fruit into the container, be sure that the fruit stays covered with the juice. If necessary, pack a piece of crumpled waxed paper or plastic wrap on top of the fruit to hold it down.

Wet packing with sugar. Sprinkle sugar (and ascorbic acid to prevent darkening, if necessary) on the fruit, and stir gently until the sugar is dissolved and the fruit’s juice is drawn out.

Strawberries sprinkled with a little sugar will freeze very well. When you thaw them, the sugar will have mixed with the natural juices to form a delicious, natural syrup.

Wet packing with syrup. Prepare a syrup by mixing the appropriate amounts of sugar and water. Depending upon what you are freezing, you may add ascorbic acid to the syrup to prevent darkening. A medium syrup (40 percent sugar) is generally good, but you might want a heavy syrup (50 percent sugar) for some tart fruits, such as sour cherries, which will benefit from the added sweetness. It will take between ½ and cup of syrup for each pint of fruit.

Be sure to treat your peaches with ascorbic acid before freezing them so that they keep their bright yellow color.

Wet packing with fruit juice or puree. This is a good alternative for folks who want to watch their sugar intake. Prepare a juice or puree from the less-perfect fruit (or use a commercial juice such as apple juice) and add ascorbic acid per the manufacturer’s directions. Fill the container with whole, crushed, or cut fruit and cover it with the juice or puree.

Sugar Syrups

When preparing syrup packs for either canning or freezing, use the proportions below. You may use honey for part of the syrup, though it will influence the flavor of the fruit. To prepare the syrup, combine the ingredients in a pan and bring them to a boil. Simmer the mixture until the sugar is completely dissolved. Depending upon the syrup’s intended use, either cool it or use it while hot. You will need approximately ½ to