Preserving Food Using A Homemade Dehydrator

Peter Murphy shares how to build your own food dehydrator and use it to preserve all of your homegrown goodies.


| July/August 1975



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With these easy-to-follow diagrams, you can be well on your way to creating your very own food dryer.

ILLUSTRATION: PETER MURPHY

Michelle and I are now living on a three-acre homestead in western Massachusetts, where we also run a small used-book store. Although we're still far from self-sufficient (after two years of working toward that goal), we add to our "do-it-yourself" skills all the time.

Preserving Food Using a Homemade Food Dehydrator

Since preserving food is an essential part of the lifestyle we're aiming for, we tried canning at home last summer. This was a new project for us, and we weren't far into the season when we discovered that we had badly underestimated the number of jars we needed. By the time we'd learned the error of our ways, canning jars and most of the other supplies that go with them were no longer available in this area. So began our search for an alternative way to preserve and store garden produce.

Freezing was automatically out because of the necessary storage unit's high initial cost and the expense of its operation. That left drying, which appealed to us for a number of reasons:

  1. A wide variety of edibles can be preserved almost indefinitely when dehydrated by any one of several methods.
  2. Dried food can be stored in a limited area (one pound of dehydrated fruit or vegetables equals three to twelve pounds of fresh produce). That's an important consideration for us because our house is very small.
  3. Best of all, even though some vitamin A and C are destroyed by this preservation process, other vitamins and nutrients are preserved at a higher level than by canning.

OK, we'd dry our harvest... but how? Ideally, in our opinion, facilities for this process should be made part of the homestead dwelling as is done in some regions of Europe. For example, in Apulia — a section of southern Italy noted for unique round stone houses called trulli — drying is carried out on the conical roofs, which are shingled with limestone, weather to a dark gray, and readily absorb and re-radiate solar heat. Access to the housetops is provided by built-in stairways.

For sure, an outdoor drying area will be part of our next homestead house. Meanwhile — since we lack adequate space to hang produce indoors — we decided to build a cabinet that would process a fairly large quantity of food with artificial heat.

The principle of our food dryer is simple: Hot air — which rises through the container from a heat source below — is baffled around and over trays that hold the produce. These racks are 5 inches shorter than the depth of the cabinet and are placed alternately against its front and back to force the warmed air to circulate through the entire box. (see the detail drawing above.)

The dryer is fairly inexpensive and easy to build. Start by constructing the two side frames out of straight, clear-grained 2 by 2's, as shown in drawing. The upper 38 inch section of each unit is then covered with 1/2 inch plywood on the outside and with 1/2 inch insulation board on the interior. The slides for the trays (1 inch by 1 inch by 29 1/2 inches) are nailed across the inside of each face from the front edge to within 1/2 inch of the rear edge (the gap at the rear leaves space for a sheet of 1/2 inch insulation board inside the back).

The sheet of insulation, 15 inch by 38 inch, is tacked to the ends of the tray slides as the first step in the dryer's assembly. Next the top piece and cross brace are attached to the front posts, and boards are nailed on or attached with screws to form the back. The top is then installed, leaving a 3 inch vent as shown in drawing. Insulation for the top is applied in two sections and nailed on from the inside.

A removable plywood chimney fits into the vent and is held in place by a 1 inch by 1 inch strip on each side. Nails are driven partway through these braces to help keep the structure rigid, but can easily be withdrawn and the chimney lifted off when the cabinet is to be stored.





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