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: 90-100°F Fruits and vegetables: 130-140°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 30-60 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**

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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. 2011. Drying

Foods (slides). Springfield, IL: The University of Illinois, Extension. Ball® Complete Book of Home Preserving, Ed. J. Kingry and L. Devine, 2006.

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