Protecting Light-Colored Fruits

Light-colored fruits, especially apples, apricots, peaches, nectarines and pears, tend to darken during drying and storage.

This process, called oxidation, robs the fruit of flavor, color and vitamins A and C. To prevent this, you must pretreat the fruit in one of the following ways:
Drying Bananas 
Cut bananas in 1/4-inch thick slices. Dip into orange juice, pineapple juice or lemon juice. Dry until leathery or until crisp, whichever you prefer.

Drying Apples 
Peel and core the apples; slice into thin rings. Coat the slices with a strong ascorbic acid solution to hold the color of the apples and dry. The apples that are best for drying are late-autumn or early-winter varieties such as Baldwin, Ben Davis, Greening, Jonathan, Northern Spy, Spitzenbury, Winesap, Rome Beauty, Red and Golden Delicious, and Russets.  

Note: For long-term storage and to insure nice color of slices, it is better to treat the fruit with sulfer. 

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