Drying Foods, Przetrwanie
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Drying Foods
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Drying Foods
Drying Foods
Drying or dehydration, the oldest method of food preservation, is particularly
successful in the hot, dry climates found in much of New Mexico. Quite simply,
drying reduces moisture necessary for bacterial growth that eventually causes
deterioration.
Successful dehydration depends upon a slow steady heat supply to assure that
food is dried from the inside to the outside. Drying is also an inexact art. Size of
pieces, relative moisture, and the method selected all affect the time required to
dehydrate a food adequately.
Methods of Drying
Foods may be sun dried with or without a solar dehydrator, in a gas or electric
oven, or with a portable electric dehydrator. Dehydrators with thermostats provide
better control over poor weather conditions and food quality than sun drying.
An effective solar dehydrator is the shelf above the back seat of a car. Clotheslines
are another popular drying rack for ears of corn and strips of jerky. Colorful red
chile ristras hung from vigas are practical as well as decorative.
Sun drying.
Prepared foods are placed on drying trays. Stainless steel screening
and thin wood lath are good materials for home-constructed drying trays. As
aluminum screening reacts with acids in the fruit, it is less desirable. Do not use
galvanized, copper, fiberglass, or vinyl screening.
Trays measuring about 14" x 24" x 1" are an easy size to handle. If trays are to be
used in an oven, they should be 1 1/2" smaller in length and width than oven
shelves to allow air circulation.
Place trays of food away from dusty roads and yards. Elevate them at least 1"
above the table with spools or bricks to allow good air circulation below the food.
Cover the food with a muslin or cheesecloth tent to protect it from insects. Dry
fruits and meats in direct sunlight; move trays periodically to assure direct sun
exposure. Place vegetables in the shade to prevent excessive color loss.
If rain threatens or food requires more than one day to dry, cover with a waterproof
material or place the food in a sheltered area.
To destroy insects or their eggs that may be on sun-dried foods and to remove
additional moisture in thicker pieces, heat foods in a 150 degree oven for 30 min.
Oven drying.
Either build trays as described for sun drying or convert oven racks
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to drying racks by stretching muslin or cheesecloth across the oven rack. Secure
with toothpicks or long sewn stitches. Alternate trays in the oven periodically to
assure even drying.
Set oven control at its lowest setting, but not below 140-150 degrees. If using an
electric oven, wedge a potholder between oven and door to allow a 1" opening.
Moisture from the drying food will vent through this opening. Close the door on a
gas oven, as into vent will permit moisture to escape.
Dehydrator.
There are two types of dehydrators: solar and electric. For each type
of dehydrator, prepare food and place on racks. If using a solar dehydrator, adjust
the position of the food throughout daylight hours to keep in direct sunlight.
Follow manufacturer's instructions for the electric dehydrators. When purchasing
an electric dehydrator, select one that has a thermostat to regulate temperature
and a fan to circulate air.
General Directions for Preparing Foods for Drying.
Refer to the tables at the
end of this guide for instructions for specific foods.
Vegetables.
Choose tender vegetables. Wash, remove any damaged areas, and
cut into even pieces. Blanch, then chill as though preparing for the freezer. Note:
Do not blanch mushrooms, onions, or sweet peppers.
To blanch in boiling water, use one pound of food for each gallon of boiling water.
Immerse vegetable into the boiling water using a wire basket or mesh bag, cover
kettle, and boil the recommended time (see table). Blanching water may be reused
until it becomes cloudy. Drain vegetables thoroughly.
To steam blanch, place 1" of water in kettle and bring to a rolling boil. Suspend thin
layer of vegetables in basket or loose cheesecloth bag. Cover and steam blanch
required amount of time (see table).
Fruit.
Choose firm, mature fruit. Wash, peel if desired, remove any damaged
areas, and cut into even-sized pieces or slices. Some fruits require little or no
pretreatment. However, pretreat apples, apricots, bananas, cherries, peaches, and
pears by one of the following methods to reduce vitamin and flavor loss, browning,
and deterioration during storage.
Immerse fruit in a solution of one of the following to a gallon of water: 1 tbsp of
sodium bisulfate or 2 tbsp of sodium sulfite or 4 tbsp of sodium metabisulfite.
These pretreatment mixtures are available from some grocery stores, pharmacies,
and wine-making shops. Soak fruit pieces for 5 min. and fruit halves for 15 min.
Note:
Approximately 5% of asthmatics are sensitive to sulfites. Use one of the
following pretreatments if sulfites present a potential health problem:
Dip fruit in a commercial ascorbic acid/water mixture from the grocery store. Follow
manufacturer's instructions when preparing and using the solution.
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Steam blanch fruit for 5-6 min.; water blanch fruit for 4-5 min. (see information on
water and steam blanching above).
Dip prepared fruit in a saline solution composed of 2-4 tbsp of salt and l gallon of
water for 10-15 min.
Meat.
Choose lean cuts of beef or venison. Partially freeze and remove all visible
fat. Slice with the grain of the meat into strips, 1" wide, 1/2" thick and 8-10" long.
Pound strips flat to tenderize and season with salt, chile, or other desired flavors.
Marinate and refrigerate overnight for additional tenderness and flavor. Popular
marinades include teriyaki, sweet and sour, soy, Worcestershire, and chile sauces.
Fish.
Slice salmon filets into thin strips. Place strips in a dish or enamel pan. Salt
strips using 2 tbsp. salt per pound. Refrigerate overnight. Oven or dehydrator
drying is preferable to sun drying fish.
Drying Times
Drying time varies widely because of the method selected and the size and
amount of moisture in food pieces. Sun drying requires the most time; an electric
dehydrator requires the least. Vegetables take from 4-12 hours to dry; fruits take 6-
20 hours. Meats require about 12 hours. Making raisins from grapes may require
days/weeks when dried outside.
When testing foods for dryness, remove a piece from the center of the drying tray
and allow it to come to room temperature. Fruits and meat jerky should be leathery
and pliable; vegetables should be brittle.
Conditioning Dried Foods
Food should be conditioned for a week before being packaged for long-term
storage. To condition food, place it in a container such as a cloth sack or a clear,
covered container and allowing any remaining moisture to redistribute itself
through the fruit.
If using a clear, covered container, watch for moisture beads. If they form, continue
drying food. If using the cloth bag, hang it in a convenient location and shake the
bag daily to redistribute food and moisture.
Storing Dried Foods
Place dried food in freezer-weight plastic storage bags, press out air, and then put
in containers with a tight-fitting lid. Store in a cool, dark, dry area.
Dried foods store well at room temperature for a month. Refrigerate foods if they
will be used within three months; freeze foods for storage periods between three
months and one year. Foods should be used within one year.
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Using Dried Foods
Dried meat, commonly called jerky, is normally not rehydrated and is eaten in the
dried state. Dried meats and vegetables used in soups rehydrate during the
cooking process.
Rehydrate vegetables by soaking them in 1 1/2-2 cups of water for each cup of
dried vegetable. If necessary, add more water during the soaking process. Heat
and eat.
Cover dried fruit with boiling water and let stand for 5 min. Drain. Dried fruit may
also be steamed for 3-5 min. until plump. Fruits may be eaten immediately or used
in a recipe.
Making Fruit Leather
Fruit leathers, also called fruit roll ups, can be made from almost all fruits or
combinations of fruits. However, peaches, apricots, cherries, and nectarines are
ideal. Pears and apples, sufficiently softened, also work well.
Wash well, peel (if desired), cut into pieces, and puree fruit in a blender. Sweeten
to taste with sugar or honey. Spread evenly, no more than 1/4" deep, on a cookie
sheet. The cookie sheet should either be lightly sprayed with a vegetable
shortening or covered with plastic paper.
If using plastic paper, tape edges down to prevent them from folding into the
puree. Dry fruit leather until it is slightly tacky to the touch.
When dried, lift leather (including plastic paper if used), and roll or cut into small
sections and roll. Storage recommendations are the same as those described
previously.
Nutritional Value of Dried Foods
Dried foods retain their protein, mineral and vitamin A content fairly well if soaking
water is also consumed. Because they are concentrated into a small mass, dried
foods can also be high in calories. It's important to brush teeth after eating dried
fruit because they stick to the teeth.
Instructions for Specific Food Drying
VEGATABLES
(See text for general directions)
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Vegetable
Preparation
Blanching
Time(mins.)
with Steam
Cooling Time
(mins.) with
Cool Water
Dryness Test
Asparagus
Wash
thoroughly.Halve
large tips.
4-6
4-5
Leathery to
brittle
Green Beans
Wash. Cut in
pieces or strips.
2-3
2
Very dry brittle
Beets
Cook as usual.
Cool & peel. Cut
into shoe-string
strips 1/8" thick.
Included in
cooking
Included in
cooking
Brittle, dark
red
Broccoli
Trim, cut as for
serving Wash.
Quarter stalks
lengthwise.
3-4
2
Crisp, brittle
Brussels-
sprouts
Cut in half
length-wise
through stem.
7-8
5-6
Tough to
brittle
Cabbage
Remove outer
leaves quarter
and core. Cut
into strips 1/8"
thick.
3
2
Crisp to brittle
Carrots
Select crisp,
tender
vegetables.
Wash. Cut off
roots and tops,
peel. Cut in
slices or strips
1/8" thick.
3-4
4
Tough to
brittle
Cauliflower
Prepare as for
serving.
5-6
4-5
Tough to
brittle
Celery
Trim stalks.
Wash stalks and
leaves
thoroughly, Slice
stalks.
2-3
2-3
Very brittle
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