DRYING FRUITS AND VEGETABLES

Source of information for this newsletter came from:  “Drying Fruits and Vegetables,”  A Pacific Northwest Extension Publication, PNW397.

Drying is a wonderful way to preserve excess garden produce.  It is a low cost method to preserve and requires less storage space than other methods.

Electric dehydrators produce the best quality dried products.  They don’t depend on dry, sunny days or take over your oven.  Drying in the sun requires proper screens, and insects can cause problems.  Oven drying uses a lot of energy and can cook food instead of drying.  Food dried in an oven takes longer and usually ends up more brittle, darker and less flavorful than food dried in a dehydrator.

Electric dehydrators should have a heat source, a thermostat with dial setting between 130 to 150 degrees F., and some method of air circulation.  Shelves should be made of stainless steel (galvanized screening is not food safe) or food-grade plastic.  A manual with directions for your specific dehydrator is also very helpful.

Select high quality fruits that are firm and fully ripe.  Use overripe or bruised fruits in leathers.  Vegetables should be fresh, tender, and just mature.

Prepare fruits and vegetables by gently washing in cold water just before drying to remove dirt, bacteria and insects.  Don’t soak for an extended time because it can cause nutrient loss and waterlog the fruit.  Core or pit the fruit and cut it into uniform halves, quarters or slices.  Trim away diseased or soft spots.

Many foods can be dried without pretreatment; however, pretreatment generally improves quality and can make food safer to eat.  Treating fruits and vegetables with an acidic solution (citric or ascorbic acid) or with sodium metabisulfite solution helps destroy harmful bacteria.  Reasons for treating food before drying are: 

1.      preserve color and flavor

2.      Minimize nutrient loss

3.      Stop decomposition (enzyme action)

4.      Ensure more even drying

5.      Extend storage life

6.      Enhance destruction of harmful bacteria during drying

Pretreat with ascorbic acid/citric acid dip, salt solution, syrup blanching, honey dip, or sulfating procedure.  Soaking fruits in water solution will increase drying time.

Blanching is the best pretreatment for vegetables.  It destroys the enzymes that make vegetables deteriorate.  Blanching keeps vegetables from browning, becoming bitter or developing off-flavors.  For water blanching, fill a kettle with enough water to cover the food.  Bring water to a rolling boil and gradually stir in the food.  Cover the kettle and boil.  The water can be reused when blanching more of the same food.  Vegetables should feel and taste firm yet tender, not fully cooked, but heated all the way through.  Drain vegetables and put into dehydrator immediately so drying can begin while vegetables are still warm.

Distribute food on trays in single layer, not over-lapping.  Dry similar sized pieces together.  Different food can be dried at the same time.  Strong foods like onion or peppers should be dried separately.  Follow directions for your dehydrator for specific times.  Generally, start with setting of 140-150 degrees F.   After 2-3 hours lower temp. to 130-140 degrees F.

Monitor drying process and rotate trays.  Drying times vary.  Vegetables are dry when brittle or leathery.  Fruits are dry when pliable and leather-like and have no pockets of moisture. Herbs are dry when brittle.  When you think food is sufficiently dry, remove a piece and allow it to cool completely.  Then check for dryness.

Conditioning fruits is a process of distributing moisture evenly in the dried fruit.  It reduces the chance of spoilage.  To condition, loosely pack cooled, dried fruit in plastic or glass containers to about 2/3 full.  Cover container tightly.  Shake daily for 2-4 days.  Excess moisture in some pieces will be absorbed by the drier pieces.  If you notice water forming on the container lid, place food back in the dehydrator.  Conditioning vegetables is not necessary.

Containers for dried food should be clean, nontoxic, moisture resistant, airtight, and protective against light.  One good method of storing dried food is to place sealed plastic bags inside a larger glass or metal container with a tight-fitting lid.

Labeling each package with the type of food, pretreatment method, and date is a good idea.

Storage area for dried food should be cool, dark and dry.