Drying Basil Turning Black

My sister is a missionary in Bolivia, she cannot get basil during a large part of the year, only when it grows fresh in season. So she has tried to dry it but she says it only turns black. And so without the modern conveniences of dehydrators there and no self-defrosting refridgerators like in the USA (as Martha Stewart suggested drying basil in the fridge), then she is at a loss as to what to do and loves basil so much she uses it all the time and so misses it when she doesn't have it during a large part of the year. Do you have any suggestions on what she could do to dry the basil while it is in season to have it later, without it turning black? If you could help I would be so so so so happy as she is doing a fine work and is on limited resources since they do their missionary work with their own saved money and do not recieve any money for it.

It is true that basil can easily turn black. We find that this happens mostly with the larger leaf varieties, and when the drying conditions are not ideal – for example in cold and damp conditions.
There are two solutions. Try cutting the leaves into smaller pieces before drying. The leaves must be cut with a razor sharp knife because you do not want to bruise the leaves too much during the cutting process. The pieces should be about 1 cm or less in length and width.
Or, try a smaller leaf variety such as Spicy Globe basil or any of the bush basil types. The smaller leaves will dry more quickly and will be less likely to turn black.