Putting Food By - Janet Greene [170]
Strong, serviceable bottoms are made by nailing ½-inch wood strips to the bottom of the frame ½ inch apart; the strips run in only one direction. More finished—but worth it, because they’re smooth and easy to clean—are ¼-or ½-inch hardwood dowels; these are nailed inside the frame with small box nails driven through from the outside, and they also go in only in one direction.
One thickness of cheesecloth laid over bottoms will keep sugar-rich food from sticking to them while it dries; so will a thin coating of oil. Some publications suggest mineral oil for lubricating the trays—it doesn’t impart flavor and doesn’t get rancid—but use any fresh, low-flavored vegetable oil. You’ll be scrubbing your trays anyway, regardless of what oil you use.
CONVERSIONS FOR DRYING
Do look at the conversions for metrics, with their workable roundings-off, and for altitude—both in Chapter 3—and apply them.
Two Good Homemade Dryers
Buy a dehydrator if you can, but if you are at all handy and enjoy doing for yourself, PFB recommends a make-it-yourself indoor dryer to set on a table. It is described in full in Circular 855, How to Build a Portable Electric Food Dehydrator, by Dale E. Kirk, Professor Emeritus of agricultural engineering, Oregon State University, Corvallis. This document is available online and includes a number of clear, very useful color photographs of the device from various angles.
A homemade dryer.
(Drawing by Irving Perkins Associates)
This dryer offers around 8½ square feet of tray surface, and thereby will handle around 18 pounds of fresh fruit or vegetables. Basically, it is a plywood box that holds five screen trays above the heat source, which is nine 75-watt light bulbs. The heat is dispersed by a shield and forced upward through the trays of food by an 8-inch household fan that is set up to blow past the vent at the base of the door.
A smaller, simpler, and more passive version is for small-scale drying outdoors with plenty of sunshine. You can put together a solar dryer that looks—and acts—much as a cold-frame does (see sketch).
The tilted glass panel—one or more pieces of storm sash are fine—intensifies the heat from the sun, and this rise in temperature inside lowers the relative humidity correspondingly, so that drying occurs faster than is possible outside the dryer. The ample screened venting allows circulation of air.
This dryer is not effective on overcast days.
PROTECTIVE COVERINGS
Food dried in the open, whether outdoors or in a warm room, needs protection from insects and air-borne gurry. Simplest to use is a strong nylon netting, as for mosquitoes; nylon because it’s easier to keep clean. Many people cut the covering 2 inches larger all around than the tray it’s intended for, bend it over, and thumbtack the overlap to the sides of the tray. Or sometimes it’s easier to stretch over several trays laid side by side. Or use a maverick window screen laid on top of the trays.
Food that’s drying outdoors must be protected from dew at night— unless it is brought inside outright. So stack the trays under a shelter and cover the stack with a big carton, or drape the stack with a clean old sheet.
The cold-frame solar dryer.
(Drawing by Norman Rogers)
MISCELLANEOUS FURNISHINGS
Trestles, racks, benches. No set sizes or types for these, so just know where you can get bricks or wood blocks for raising the first course of trays off the ground; scrap lumber for building rough benches or racks to hang drying food from; smaller stuff to use as spacers.
Sulfuring box. We’re going to suggest sulfuring in certain instances, and we’ll tell how to make and use a sulfuring box in a minute.
Auxiliary heaters. Easier to list what not to use: no small stove burning flammable material—wood, oil, coal, etc.—that sits inside any portion of the indoor dryer. Never any sort of front-blowing electric heater laid on its back to blow hot air upward. Avoid