Drying

An ancient way of preserving food is to dry it. This can be done at home by using an electrical dehydrator. They come in different classes.
Dehydrated foods are also considered to be part of the raw food movement, since the water is removed from a raw food at very low heat, leaving many of the nutrients and enzymes intact. You can dry slices of apples, oranges, lemons and berries of all kinds, pineapple, mango, papaya, pears, kiwi, banana, tomato, plums, parsley, carrot, bell pepper, onion, chili, coconut, herbs and mushrooms. The list is as long as your imagination.
Give your items a citrus bath. It is used with some fruits and vegetables to lock in enzymes and avoid browning of the item's flesh.
Here follows three links to amazon.co.uk and two links to amazon.com. All in the lower price range.

Oypla Electrical Dehydrator
Clatronic DR-2751 Food Dryer
Paderno Dehydrator
AmeriHome
WYZworks Stainless


Also amazon.de have some nice offers.
The dehydrator typically works in the range of temperature 35-70°C. They mostly have a capacity of 5 to 10 trays. The systems work by blowing/circulating warm air around inside the machine. The trays have holes in them, so that the air can get around and dry the items.