Cold storage: keeping vegetables fresh all winter
Cold storage is an old-fashioned but time-tested method for keeping raw, whole vegetables through the winter. If youve planted a big vegetable garden and if youve got (or can construct) the storage space, storing can be the most practical way to go.
Youll find many vegetables from your garden well-suited to cold storage, including beets, carrots, onions, parsnips, potatoes, pumpkins, sweet potatoes, turnips, winter squash, and many others. For a complete list, see "Directions for storing vegetables," later in this chapter. Other vegetables should be used fresh or preserved. Vegetables that are not suitable for cold storage include asparagus, fresh shelling beans, green beans, chayote, corn, cucumbers, eggplant, fresh greens ? beet greens, chard, cress, dandelion, endive, lettuce, mustard, and sorrel ? fresh lentils, mushrooms, okra, green onions, fresh peas and chick peas, fresh peanuts, new potatoes, radishes, rhubarb, fresh soybeans, spinach and New Zealand spinach, summer squash, and ripe tomatoes. Shelled dried beans, lentils, peas and chick peas, soybeans, and dried peanuts can be kept up to one year in cold storage.
Late-ripening and maturing vegetables are the best choices for cold storage. Certain varieties take better to this method than others? late cabbage, for example. Check seed catalogs and packets before you buy and plant, and talk to the specialists at your County or State Extension Service Office. They can help you decide what vegetables to plant when youre planning your garden, and what storage methods work best in your area.
How cold storage works
Like any other method of food preservation, cold storage keeps food from decomposing by stopping or slowing down the activity of enzymes, bacteria, yeasts, and microbes that can eventually spoil food. In cold storage, this is done by keeping fresh, raw, whole vegetables at temperatures between 32?F and 40?F. In this range, the food wont freeze, but it stays cold enough to stop the spoilers. The length of storage time varies with each vegetable, from a few weeks for broccoli or cauliflower to four to six months for potatoes. Dried beans and peas will keep the longest?10 to 12 months.
One of the advantages of storing your vegetables is that you dont risk eating unwholesome, spoiled food. If the food goes bad, you can tell almost immediately by the way it looks, smells, or feels. But theres still a lotto learn about storage. For example, squash have to be kept warmer than do carrots, so these two vegetables cant be stored In the same spot. Or, if you plan to keep cabbages or turnips, dont store them indoors in the basement; youll soon find their strong, distinctive odor penetrating up into the house. And, if you live in a climate where heavy snow is common in winter, outdoor storage of vegetables in mounds or barrels isnt going to be practical foryou, because deep snow will make them inaccessible In winter.
Although storing vegetables may sound easy, its a lot more complex than at first meets the eye. Although you dont have to do any chopping, blanching, or processing of vegetables to be stored, each vegetable does have to be handled in a special manner. Perhaps the trickiest part of all is that youve got to keep a weather eye on your stored food. Since the temperature of cold storage depends on the temperature outdoors, you may sometimes have to move or change the location of stored vegetables, open windows or vents, or adjust the humidity level. When storing food indoors, keep a thermometer as well as a humidity gauge in the storage area so you can accurately monitor temperature and moisture conditions.
Because its harder to control the temperature of stored food, spoilage can happen more easily than with any other form of food preservation. Routine checks for spoilage will help you prevent food losses when storing vegetables indoors ? but, once you open up an outdoor mound or barrel, youll have to empty it of all the stored vegetables at once.
Storage methods for vegetables
Before the days of refrigerators, freezers, and supermarkets, most families depended on cold storage to keep a supply of vegetables all year long. In colonial times, a certain portion of every harvest was kept in cool caves or in straw-lined pits that could withstand freezing temperatures. In latertimes, most houses were built to include root cellars or cold, damp basements intended as storage areas. These chilly spots were perfect for keeping root vegetables, celery, pumpkin, squash, potatoes, arid other vegetables through the cold months.
Compared to houses of a century ago, our modern dwellings are snug, warm, and dry. Today, very few homes offer the cool, damp basement corners, outdoor sheds, or attics that formerly served as food storage areas. That means youll have to plan, and perhaps construct, one or more special spots for cold storage of your gardens bounty ? particularly ifyou plan to store a variety of vegetables.
In milder climates, where frosH is infrequent and doesnt penetrate too deeply, vegetables can be kept in specially prepared outdoor locations. In colder areas, youll have to store the vegetables indoors as an extra precaution against freezing. In the directions for storing vegetables that follow, youll find the proper storage method for each vegetable.
Four vegetable groups
Where and how you store each vegetable will depend on how much or how little cold it can take and the amount of humidity it needs to keep fresh. Vegetables to be stored fall into four groups: cold-moist, cool-moist, cold-dry, and cool-dry.
Vegetables that should be cold-moist stored make up the largest group, and include beets, broccoli, Brussels sprouts, cabbage, carrots, cauliflower, celery, turnips, and many others. These vegetables require the coldest storage temperatures ? 32?F ? and the highest humidity ? 95 percent ? of all vegetables that can be stored.
The second group of vegetables requires cool-moist: melons, peppers, potatoes, and green tomatoes. These vegetables can be kept at temperatures ranging from 38?F to 60?F and at humidity levels of 80 to 90 percent.
Dry onions and shallots require cold-dry storage temperatures of 32?F to 35?F and humidity of 60 to 75 percent.
The cool-dry group is composed of pumpkin and winter squash, dried peas and beans, and live seeds, all of which must be stored at temperatures of 50?F to 55F and at a humidity of 60 to 70 percent.
Vegetables in the cold-moist and cool-moist groups can be stored outdoors in a mound or barrel, or indoors in a specially insulated basement storage room that is partitioned off from the central heating area or a root cellar. Vegetables in the cold-dry and cool-dry groups can be stored indoors in a cool area of a heated basement, but they must be kept away from water that might condense and drip down from overhead pipes. Cold-dry storage can also be provided by a dry shed or attic, window wells, or cellar stair storage.
The accompanying chart shows how vegetables in each of these four groups should be stored ? at what temperature, at what humidity, and for how long. Any one of the storage methods discussed in this chapter can be used if it supplies the necessary conditions of temperature and humidity. For some vegetables in the cool-moist group, the refrigerator is an ideal storage area. And when cold storage doesnt add significantly to the length of time you can keep a vegetable from the cold-moist group, you may prefer just to refrigerate your crop, as detailed above.
Recommended storage conditions