Putting Food By - Janet Greene [100]
There is also the re-usable container like a coffee can with an extra plastic lid: for your seal, tape the lid to the can all around.
The lids for glass jars must have an attached rubber-composition ring or a separate rubber ring to make a seal.
The lids for cans are put on with their own special sealing machine, as effectively for the freezer as for the Pressure Canner.
SEALING NON-RIGID CONTAINERS
Freezer bags are best sealed by twisting and folding the top, and fastening them with string, a rubber band, or a strip of coated wire.
Heat-sealing is possible—but it’s tricky unless you have the special equipment for doing it. (Again, see Chapter 17.)
Non-rigid sheet wrappings sometimes can be heat-sealed, but people more often seal all the edges with freezer tape.
LABELING
Use a wide, indelible marking pen to label each package with the name of the contents, the amount, and the date packaged. Also tuck a slip bearing this information inside a clear bag of food.
MAXIMUM FREEZER STORAGE FOR BEST QUALITY MAINTAINED AT ZERO F/−18 C
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Freezing Fruits
Use only perfect fruit, and treat it with respect. You’ve invested a good deal of money in a freezer, your packaging materials cost a bit if they’re good-quality food-grade re-usable containers; add your time, your freezer’s portion of the monthly bill for electricity, and all these items require that your raw materials be top quality to start with.
Handle only a small quantity at a time—2 or 3 quarts. A good way to wash fruits: put them in a wire basket and dunk it up and down several times in deep, cold water. After peeling, trimming, pitting, and such, fix fruits much as you would for serving. Cut large fruits to convenient size, or crush. Small ones, such as berries, usually are left whole, or just crushed.
Crush soft fruits with a wire potato masher or pastry blender, firm ones in a food chopper. To make purée, press fruits through a colander, food mill, or strainer. (Blenders can liquify too much; food processors liquify even more unless you’re careful—the directions for your processor are reliable here.)
Headroom for Fruits
If you use rigid containers—as against bags alone or inside protective paper boxes—you must leave ample headroom so that the expansion of the food during freezing doesn’t force off the closures.
The wide-top containers referred to in the following chart are tall, with sides either straight or slightly flared. The narrow-top containers mentioned include canning jars, which may be used for freezing most fruits that are not packed in liquid.
CONVERSIONS FOR FREEZING FRUITS
Do look at the conversions for metrics, with their workable roundings-off, and for altitude—both in Chapter 3—and apply them.
To Prevent Darkening
Apples, apricots, peaches, nectarines, pears, and other oxidizing foods are kept from darkening by the addition of ascorbic acid (Vitamin C) either crystalline or tablets; commercial mixtures with an ascorbic acid base; crystalline citric acid; or plain lemon juice. Or steam-blanching for 3 to 5 minutes, depending on size of the pieces, may be used.
Fruit has a tendency to float to the top, where it changes color when exposed to the trapped air; so crumple some moisture-resistant food-grade sheet wrapping and put it on the top of the packaged fruit to hold it below the syrup. Seal and freeze.
Ascorbic Acid, Crystalline
Usually available from natural food stores and health-supply shops or drug-stores. If bought in ounces, figure 1 ounce will give roughly forty ¼-teaspoons or twenty ½ teaspoons (these being the most common amounts called for in freezing). Less expensive are Vitamin C tablets of 500 mg to crush; see Chapter 5 on “Common Ingredients.” There is no record of known undesirable side effects from using ascorbic acid to hold the color of processed foods. It is Vitamin C.
YIELDS IN FROZEN FRUIT
Since the legal weight of a bushel of fruits differs among states, the weights given below are average; the yields are approximate.
It is the most effective of the agents employed