Home & Heart Kathleen Jarschke-Schultze I have been working on solar food drying in some capacity for years. Now I have built the most ambitious (for me) dryer yet. I am well pleased with the results and expect to dry many foods from my garden this year. Dry History The first solar food drying I can remember is a wooden table set up by Aunt Anna's grape arbor. We would pick the grapes and eat them but Aunt Anna would spread them to dry under cheesecloth. That's when I realized dried grapes were raisins. Then when I first lived with Bob-O we had a lot of peaches and strawberries one year. I laid out cookie sheets lined with freezer paper and poured fruit puree into them. After covering them with plastic and waiting a couple of sunny days I had fruit leather. Presently After a question from a reader and a request in this column, I received a lot of information on food drying. (See HP #29) The model I chose to make was Lucien Holy's Active Dry Climate dryer. I was very ambitious and got a very large box for the drying area. Then we had rain. Even on the covered porch, where I thought it was protected, it took a direct hit and lost its shape completely. Time was running out for me. Then we got a component shipment in a plywood box. It was small, sturdy and put together with Makita wood screws. My kind of materials. Meanwhile my mother had given me her old electric food dryer. I considered running side by side tests. When I saw that the power draw on the electric model was 600 watts I decided differently. However the shelves in the unit were really nice. They measured 2 foot by 2 foot of washable white plastic trays with a liner of food grade plastic screening. I realized that the plywood box would work if I added 2.5 inches to each side of the box. It took me one day to accomplish this. I also cut a hole in the top and placed a small 12 V muffin fan there to draw the air on through and out of the drying chamber. The fan was powered by a Solarex SA-2 amorphous silicon module. Although it is designed to be a 6 volt battery "charge maintainer", it runs the fan from first light to dusk. I took one half of a Kyocera PV panel cardboard shipping box, cut the sides on a diagonal, cut along the front and painted the inside black. After cutting vent holes in the ends of the box and one side of the dryer box I thought I was ready to apply the Saran Wrap glazing. I had not considered the windy qualities of our canyon home. After due deliberation, I carefully chose some flat rocks and placed them into the collector. I reasoned that not only would they hold the darned thing down, but would act as heat sinks and keep the air warmer longer as the sunlight changed position. On with the glazing and I was done. On the dryer box I added hinges and two wooden knobs so I could hold the door tightly shut with a large rubber band. Fruit & Veggies Since the only thing my garden was producing at the time were artichokes and snow peas I went shopping. I chose two kinds of tomatoes, seedless grapes, plums, apricots, pineapple, bananas and green peppers. Some I blanched, some I did not, according to the type of food. I weighed the food before I dried it and afterwards. I cut rather large pieces of everything. I like dried apricot and banana halves. I quartered the Roma tomatoes for sun dried tomatoes. I knew it would take a little longer to dry, but I felt the food would look better. Drying Time I started drying the foods at 10:45 one morning. This would give them the better part of a day to get the surface moisture out. I had placed a thermometer in the collector. For most of the day it read at 150ø F. The ambient temperature was around 85ø F. The air coming from the dryer box through the fan had a wonderful tropical smell. I was eager to see if the dryer worked so I must have checked it three or four times that first day. I did not remove the food that evening. The next morning I checked and it did not seem to pick up any appreciable moisture in the night. By the end of that second day the smaller pieces of food were leathery. The third day most of the food was dry. The apricot halves took another day, though. I noticed that one grape had not dried at all, but was just as juicy as when I first set the tray in. I had blanched the grapes, then plunged them into cold water to crack the skins. This allows the moisture to escape during the drying process. Apparently this one grape's skin didn't crack. This graphically illustrates what an important step the blanching is. Correction In the Things that Work! on the Bar-B-Que Box in HP# 28, Bob Taylor is listed as the maker. Bob distributes the Box but does not make it. Access Kathleen Jarschke-Schultze is drying her heart out and can be reached c/o Home Power Magazine, POB 130, Hornbrook, CA 96044 ù 914-475-3401