With the three ways of preserving traditionally being freezing, cannning and drying, the only method that keeps food in its "raw" state nutritionally speaking is the drying method. That is, if it is done properly.
Drying fruit is one of the oldest ways of preserving extra, and also very easy. If done properly, dried fruit can be preserved with little nutritional loss for many years. Most people understand that canned and frozen food only last about a year at the most, and would not even think of using 5 year old canned food, for instance.
Recently, I opened a jar of dried peaches that I had attended in September of 1999, and to the great delight of my 13 year old, who was born in 1999, we enjoyed some peaches that were harvested and dried 13 years ago.
I know, some people may think, "yuck" they must've been yucky or black, or whatever. They were not!
The advantage to drying fruit at home the natural way is that YOU control the temperature, the quality of fruit, and the use or non-use of chemicals in the process. When drying fruit at the optimum temperature range, the fruit retains its color, enzymes, taste, and overall nutrition.
Dry fruit correctly can reserve the fruit for many years, rather than the usual recommended one year. It is sort of like the grain that was found in some Egyptian tombs that still sprouts because it was preserved properly.
Now, some nutrition and taste may be lost on older fruit, but for the most part, it is intact when done correctly.
The 13 year old peaches that we opened recently were great -we loved them, and they are the same golden color they were when I first dried them.
One note about drying fruit for the long term: if you want your dried fruit to last for more than a year, dry it longer, til it is "breakable, not bendable." If you are drying fruit more for short term use, then leaving it softer is fine, and can be more enjoyable for some.
Drying fruit is easy, with the right equipment. Not all food dehydrators are made equal. We use an Excalibur dehydrator, since the fan blowing from the back does not circulate the air, which is more effective in drying fruit.
So, usually the fruit is cut into 1/4 inch pieces, and laid on the sheets to dry. Bee Beyer's book, Food Drying at Home the Natural Way, is the best book on the subject, in my opinion, and goes into detail about any variations in cutting and drying times.
I typically leave my drying fruit on the dehydrator for 3 days, at her recommended temperature of between 110-118. The low temperature preserves the color, taste, and most importantly the enzymes and nutrition.
Dry fruit is so easy, my children love to do it – "grazing" as they go, of course! :)