Alchemical Blog

Hello everyone, I would like to share with any interested readers a project that I'm working on as part of an internship I'm doing at the Alchemical Nursery Project.  I've become very interested in food preservation as a means of allowing us Central New Yorkers to eat locally all year 'round.  I'm particularly interested in food dehydration as the cheapest, most energy efficient, most space efficient method I know of, which is also comparably great for preserving nutrients and flavor.  Best of all, I've learned that you don't even need to purchase equipment to dehydrate food - we can dehydrate food simply by harnessing the sun's rays!  

Solar dehydration is an ancient food preservation method that in many climates requires nothing more than laying food out in the sun.  In CNY, however, our temperature and humidity may mean a little more work.  In doing a little research, I found a design for a solar dehydrator that can be built almost for free.  Here's the design, which can be found at http://www.ehow.com/how_4901341_build-own-dried-fruits-vegetables.html :

 So, I decided to try making one of these contraptions to see how it can really work.  In roughly 6 hours I put together a solar dehydrator with the following materials: 2 cardboard boxes, duct tape, plastic wrap, cheese cloth, a black garbage bag, a milk crate,  drying racks from an electric dehydrator, and a magic eight ball.  

Today at about 3:00 I put the dehydrator out on my roof.  The outside temperature was about 75 degrees, and the sky was clear and bright.  Within an hour, the temperature in the dehydrator reached about 120 degrees, the minimum temperature necessary for efficient dehydration.  Given adequate sun, I'm going to test it out with some fruit this week.  I'll  let you know how it goes.  In the meantime, here are some pictures: 

This is the dehydrator set out on the roof above the porch.  This spot gets perfect sun after about noon, and is conveniently very close to the kitchen.  Notice My design is slightly different than the model.  I'm going to test this out with the lid closed but not sealed, hopefully to keep the heat in, but to still let heat ventilate out.  The magic eightball is simply a weight to keep the lid closed.

 The hot air chamber is lined with a black trash bag to absorb heat, and is covered with plastic wrap to trap the heat.  It has three holes on the bottom and three on top, covered with cheesecloth, which allow air to flow up into the dehydration chamber.  Air flow is one of the key aspects of successful dehydration.   

 Here you can see the electric dehydrator trays set in the dehydration chamber.  Since I had these, I figured it be easiest to use them, however, it's quite possible to make trays from scrap objects as well.

Here's the inside without the trays.  Notice that the cardboard will prop up the trays and direct the air so that it flows directly under the lowermost tray and up through the rest.  Also notice the oven thermometer for monitoring the temperature.

And here's a close-up of the stacked trays.