Food Preservation Methods

This section describes general methods of food preservation. For detailed canning, freezing, drying, or root cellar storage procedures, look in the chapter that covers that food—for grains, Chapter 3; for herbs, Chapter 5; for fruits, Chapter 6; meats, Chapter 8. For vegetables, look in Chapter 4; pickles are mostly discussed under "Cucumbers" and sauerkraut making under "Cabbage" in that chapter. In-Ground Storage: Some people say you should leave most of the root vegetables in the garden during the winter, even after they're grown, rather than using other preserving methods. Parsnips and salsify are about the be$t for that; they're often left in the ground over winter with a mulch over them. But I tried that and despaired. Every time I wanted something out of the garden, the ground was either frozen so solid that I couldn't dig it up, or it was so wet and muddy that I could barely manage to pull my legs back out of the garden soil, much less bring an armload of vegetables with me. If the ground freezes down far enough to freeze your vegetables, they will get soft and be no good anyway (except for leeks). I guess it depends a lot on where you live or what your garden storage system is. For more information, see "Extended Season Gardening" in Chapter 2. Deterioration in Storage: We share this wonderful world with myriad invisible but ravenous little critters who love to eat exactly the same things we do. The food preservation game is to get a move ahead of them and "enzymes," which are chemicals contained in the food itself that can cause undesirable changes. Salt, sugar, alcohol, sodium benzoate, and sulfurous acid are "chemical" preservatives that, in effect, poison or make the food yucky to the beasties. Drying food makes it impossible for them to grow and reproduce in it. Freezing puts them into hibernation except for the most cold-hardy, which can then double their number only in months, perhaps, rather than in hours. Canning, when you do it right, kills every last beast in the food and seals it up tight so that no more can get in. Cellar storage takes advantage of certain living foods' natural defenses against spoilage.

All stored foods, no matter how they are stored, slowly but steadily lose quality and nutritional value as time goes by. Some foods deteriorate faster than others. If a food was on the verge of spoiling when you started, it may lose quality more quickly in storage. Some storage methods, such as canning and drying, hold the food better than others. The biggest single risk factor for most stored foods is warmth, which causes the loss of both nutrition and palatability. With few exceptions, the cooler it is (above freezing for nonfrozen foods), the better they keep. For every 20 degrees' increase in storage temperature, you lose one half of the possible shelf life of most stored foods. The ideal storage temperature is 38-40 E

The Basic Methods: There are 6 basic methods of food preservation: canning, freezing, drying, pickling (for salt, vinegar, and spices), sugaring (for jams and jellies), and root cellaring—underground or even in the garden (live storage). Root cellaring is the oldest method, but not all foods store well using that method; in fact, most don't. Freezing is the most popular method and the next easiest, but it's also the most expensive, and you have to own a freezer and have electricity Canning takes the most time and effort, but the food can be safely kept (if you carefully follow the rules) and stay delicious. preserving Meat: Our family of 7 (and very often extras) can use 2 big calves, 4 pigs, maybe half an elk, and 50 or more chickens a year. The pigs supply cooking grease as well, which can be canned or stored in the deep freeze. Without electricity to run a deep freeze, you can't keep meat frozen, except if you live where there is a really bad winter—and even then, only during that winter. In most places, your outside temperature will be below freezing sometimes, but you'll also get off-season thaws that could spoil the meat. So, without electricity, you'll have to either rent a locker in a nearby town, which doesn't cost much, or can most of your meat right after butchering. That's what the old-timers did, and they ate well. You can also dry the lean meat in small strips—jerky. But that isn't as tasty or chewable as canned meat. You can can the meat from any kind of animal; just bone it out first. Another food preservation system for meat is making mincemeat at the beginning of the cool season. It will keep during the winter months in a cold, outdoor place. cost Comparison: Another way of comparing preserving systems is by their cost. From that point of view, in-the-ground in your garden is cheapest. Root-cellar storage is next, because you build the cellar and then have no additional expense. However, drying can be cheaper than root-cellar storage if you have to factor in the cost of a root cellar, for if you're drying with simple sunshine, drying is free. If you're using an oven or dehydrator, it isn't.

Canning is a bit cheaper than freezing—even taking into account the cost of new jars, some sugar to add to your fruit, and the electricity it takes to heat your canner. If you live where electricity is expensive, the cost of canning can be as little as half the cost of freezing. On average, the electricity to keep 2 cubic feet of freezer space cold for 1 year in the Northwest will cost $7.68. On the other hand, electricity to can the equivalent amount of food (assuming peaches here) on high heat for IV2 hours would be only 13 cents. But electric costs vary wildly depending on where you live. Here in the Northwest, we have just about the cheapest rates in the country. If you're canning on a wood stove and have your own wood supply, then you don't even pay for electricity, and once you have your basic jar collection, new lids are your only expense. Electricity to dry that amount of fruit would cost about 40 cents. Freezing is the most costly method because you have to buy a freezer and pay for electricity and wrapping material or containers to freeze the food in.

Nutrition Loss in Storage: But also consider, according to the USDA, that foods lose 60-80 percent of their nutritional value when they are canned, because of the high canning temperatures and water soaking. (Storing canned goods in a dark place minimizes the loss of riboflavin, which is caused by exposure to light.) Canned goods also lose vitamins from exposure to warmth. Frozen foods lose only vitamins E and B6, but if stored above 0°F, they can also lose a considerable amount of vitamin C and other nutrients, up to 40-60 percent of their food value. Blanching before dehydrating helps hold vitamins. Dehydrating using very low heat levels is less destructive of nutritional value than sun drying. However, dehydration results in more nutrition loss than any other form of food preservation. Live storage (in a root cellar) is the best of all for holding nutritional value, so long as the food doesn't freeze, the storage is cool, and the food is an appropriate one for this method. Heat, oxygen presence, and passage of time all cause losses.

Nutritionists are most concerned about what happens to vitamins A and C. Vitamin C is totally lost after sun drying foods (80-90 percent is lost after drying in a dehydrator) but is 100 percent retained in freezing. In canning, 25 percent of C is lost from fruits and 50-90 percent from vegetables. So they recommend that you dry or can highvitamin A foods but freeze high-vitamin C foods. Summing up Non-Food Factors: Root cellar storage is cheapest of all and will retain most of the nutritional value. Of canning, freezing, and drying, freezing is quick and easy, but the most expensive; drying and canning are both cheap, but drying is by far the worst in terms of loss of nutritional value.

The Food to Be Stored: Yet another factor is that there are one or two best methods of keeping any single type of food. Sometimes even a particular variety of plant will keep better by one method than another. In my opinion, tomatoes, large fruits, syrups, fruit butters, and juices are all best kept canned. Cucumbers and cabbage are best pickled (preserved in salt). Green beans are good either canned or frozen. Corn, greens, peas, baby turnips, baby carrots, extra bread, meat, and hides waiting to be tanned are in my freezer. Berries are better frozen than canned. Fruits, except berries, are also very good dried. Apples are good made into sauce or butter and canned. Or you can dry apple rings or freeze slices in syrup for pie making. Onions, beets, green tomatoes, potatoes, winter squash, pumpkins, big turnips, big carrots, and celery will keep best in the root cellar. I didn't include drying in this list, but if you live where there's lots of dry, hot sunshine, this is also a wonderful option. Even if you don't and have to use an oven or dehydrator, it still may be a great option!

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