To prevent and slow oxidation resulting in discoloration and spoilage in fruits being prepared for dehydration, sliced fruit can be treated with a soak in fruit juice. Essentially this works the same way as treatment with ascorbic acid, and though it is not as effective as using a pure ascorbic acid solution, it is easier in a pinch than tracking down powdered ascorbic acid or crushing vitamin C tablets.
Your choice of fruit juice will impart additional flavor in whatever you're drying. If you find yourself with a surplus of particularly boring-tasting apples to dehydrate, consider spicing them up with a fruit juice pre-treatment with lemon, lime, cranberry, or pineapple juice instead of sulfites.
Basically, you can use any juice that is naturally high in ascorbic acid (vitamin C). I prefer lemon in most cases, but lime, orange, pineapple, cranberry, and pineapple juice will also be effective.
Directions for treating fruit with a fruit juice dip:
- Fresh-squeezed juice is preferable to pasteurized, as heat can degrade vitamin C.
- Submerge the sliced and prepared fruit completely in the juice for 3 to 5 minutes.
- Drain and remove the fruit, and place in the drying racks.
- The fruit juice can be used for a total of two soaks.