I've heard rumors of hanging up fresh, thinly-sliced mango in a kitchen and just leaving it there for a few months to dry out. Has anyone experimented with this or other such projects?
I put 2lb pitted cherries on parchment paper on a sheet tray in a low oven for about 6hr and they came out great... brought them to the beach as a snack and ate them all in one sitting. Been thinking about what to try next. Have always mulled getting a dehydrator but still want to see if I can manage without it. I think it's more energy-efficient to have if you're dehydrating anything in real volume, but otherwise not worth counter space (at least for me). What else are you thinking of doing besides mango?
I used to have a wooden dehydrator that you would sit out in the sun. The fruit (or veg or herbs) would sit on a screen raised up from the bottom, and the top was a piece of plexiglass. To prevent delicate herbs from losing their color, you could put a black piece of poster board below the plexiglass. It was awesome and worked perfectly. If you know someone who's good with wood, you might think about getting them to make you one.
I wish I could use one of those!! Too bad I have no outdoor space. One day, one day....
Food dehydration is an interesting area of food preservation, and the "best" way to do so will vary geographically -- not just because of the produce that is available but also because of climate issues -- hot and arid works really, really well for dehydration. The higher the humidity the more difficult to get a good result; same with cooler weather. Regardless, product may take several days to fully dry and must be brought covered or brought under shelter at night to prevent condensing cool night air from adding back moisture.
So, having said that, the tried and true is a food dehydrator. You can also use the lowest setting on your oven but for most cases it isn't the same since your oven likely won't go low enough. The optimal temp for true dehydration is 140F. You can use your oven at its lowest setting but the greater the difference between that setting and 140F, the more you are cooking rather than dehydrating, which affects more the quality of the final product than food safety.
Most dehydrated product also benefits from post-dehydration "conditioning". This is simply putting the product in an airtight container (canning jars with the top screwed tight work particularly well) and shaking well a couple of times a day for about a week. This helps equally distribute any residual moisture among the entire product, reducing the likelihood of spoiling.