Popcorn must be well dried to pop properly; otherwise it will simply become cooked corn. Whether drying corn to make popcorn or re-drying popcorn that has become soggy, you must dry the corn carefully and completely. Only a hardened, fully dried kernel will form the best popcorn.
Spread the kernels of popcorn on the tray of the food dehydrator. Make sure the popcorn is spaced out so that air can get between each of the kernels.
Set the dehydrator to 130 degrees, and allow time for the dryer to preheat.
Insert the tray into the dehydrator, and leave it to dry for 10 minutes. Check the popcorn every 10 minutes to see if it has dried sufficiently.
Let the kernels cool slightly when you check them for dryness. Use your fingers to feel the kernels in order to get a sense of their dryness. A well-dried kernel will feel leathery and slightly sticky.
Remove the popcorn when it is properly dried, and leave it spread out to allow it to cool completely. When it is cool, store it in a well-sealed airtight container to preserve its freshness.