DRYING FRUITS AND VEGETABLES

Food Dehydration  Heat: removing moisture, but not cook  Dry Air: to absorb released moisture  Air Circulation: to carry the moisture away  Inhibits bacteria, yeast & mold growth  Prevents food spoilage  Slowing down enzymatic activity

Dry Food Safely  Peak quality  Clean preparation areas and containers  Use food grade equipment and containers  Protect food from Air Moisture Light Insects, pests/vermin

Temperatures for Drying  Herbs, nuts and seeds: °F  Fruits and vegetables: °F  Meats and fish: 160°F  Drying too slow = microorganisms could grow  Drying too fast = cooked food or case hardening  Avoid “case hardening” – dried outside and moisture is trapped inside – mold results

Drying Methods  SUN: not recommended in Rhode Island…need several days of high temp and low humidity  OVEN: slower than dehydrators  FOOD DEHYDRATOR

Dehydrator Features  Double wall construction of metal or high grade plastic, not wood  Enclosed heating element  Counter top design  Enclosed thermostat from 85ºF-160ºF  Fan or blower  4-10 open mesh trays, plastic, sturdy, washable  UL seal  Dial for regulating temp  A timer, auto- shut off

Types of Dehydrators  Horizontal Air Flow Heating element and fan are located on side Major advantages – reduces flavor mixing  Vertical Air Flow Heating element and fan located at base Major disadvantage – flavors can mix

Indoor Air Drying  Herbs, hot peppers, & nuts in shell most common  Tie in bundles  Enclose in paper bags, with openings for air circulation  Spread in single layer on paper

Drying Fruit  Wash and core  Fruits can be halved, sliced, or whole  Thin, uniform, peeled slices dry fastest  If fruit dried whole, crack the skin to speed drying – cranberries – place in boiling then cold water to “check”

Pre-Treating the Fruit  To prevent fruit darkening caused by oxidation  Optional  Sulfuring**  Sulfite Dip**  Ascorbic Acid  Ascorbic Acid Mixtures  Syrup Blanching  Steam Blanching ** can cause an allergic reaction in some people

Drying the Fruit  Place fruit in single layer  Follow directions given  Follow approximate drying times given  Watch food as it dries much faster at the end of drying period

Determining Dryness of Fruit  20% moisture content when dried  Cut several cooled pieces in half, should not: see visible moisture be able to squeeze moisture  Not be sticky or tacky  If piece folded in half, shouldn’t stick to itself

After Drying…  Cool fruit minutes before packaging…don’t pack too soon or moisture buildup could occur…don’t wait too long or could pick up moisture

Conditioning Fruits  Conditioning equalizes the moisture.  Pack cooled fruit in plastic or glass jars, seal and let stand for 7-10 days  Shake jars daily to separate pieces and check for moisture condensation  If condensation, return to dehydrator for more drying…unless has started to mold, then dispose of

Drying Vegetables  Preparing the vegetables Wash, trim, peel, according to directions Uniform pieces Dry as soon as possible after picking

Pre-treating Vegetables Water blanching Recommended times Start timing when water returns to boil Steam blanching ≤ 2 inches above boiling water Heated through, but not cooked Lose less water-soluble vitamins & minerals

Cooling Vegetables  Cool  Wipe vegetables  Place in dehydrator

Determining Dryness of Veggies  Dry vegetables until brittle or “crisp”  10% Moisture  Don’t need conditioning like fruits, because they have a lower moisture content

Drying Jerkey  Jerky can be made from: Meat (sliced cuts, ground) Fish (fillets) Poultry (breasts)  Two drying methods Dry, then heat Heat, then dry**

20 Disclaimer:  Trade and brand names are used only for information. The University of Rhode Island does not guarantee nor warrant published standards on any product mentioned; neither does the use of a trade or brand name imply approval of any product to the exclusion of others which may also be suitable. Document Use:  So Easy to Preserve, 5th Edition, 2006, University of Georgia Cooperative Extension Service  Adapted with permission of the University of Illinois. Finck, J Drying Foods (slides). Springfield, IL: The University of Illinois, Extension.  Ball® Complete Book of Home Preserving, Ed. J. Kingry and L. Devine, Robert Rose Inc. Photography Credits  Elizabeth Andress and Elaine D’Sa, National Center for Home Food Preservation, University of Georgia.  Information Staff, Agricultural Research Service, USDA.  North Caroline State University