The high acidic content of lemon juice will prevent fruits, like apples and bananas, from turning brown during dehydration. Let your fruit soak in a half-and-half mixture of lemon juice and water for five minutes before putting it on the drying rack.
To ensure that your fruits, vegetables or meats all dry evenly make sure that you cut each piece the same size. This will ensure that whatever you are drying will be done all at the same time. The best way to get consistent slices is by using a food mandoline.
Fruit leather can be a messy project if your dehydrator has grated trays, like this Excalibur 9-Tray Digital Controller Food Dehydrator has. A disposable option is lining your trays with wax paper. If you want a more permanent solution, invest in fruit leather trays for the best results and easy cleanup.
Dried veggies are great, but make sure to steam any low-acid vegetables like snow peas or carrots for 10 minutes. Pat them dry with a clean towel before you put them in the dehydrator for the best results.