Dehydrating food

Dehydrating
to Preserve Food

from Theresa

Our electric dehydrator.

Dehydrating may be the best way to preserve food:

It was the main method used to preserve food to survive the Winter months before the advent of canning or freezing.
It uses a minimum amount of the planet's resources. Even if you're using an electric dehydrator, it uses much less electricity than it takes to boil pots of water for canning and much less than it takes to keep food in the freezer for months.

Dehydrated food shrinks, so takes a lot less space to store than any other food preservation method. For example, my electric dehydrator holds 4 lbs of green beans, which, when dehydrated, fit into a pint (2 cups) jar.
Dehydrating is much less labor intensive than canning. You only have to chop and arrange the food on the tray, check it periodically, then remove and store it when it dry.
Dehydrating can be used to preserve fruits, vegetables, meat, and herbs & spices.

This pint jar is actually storing 4 lbs of green beans.

Ways to dehydrate:

Electric dehydrators: For years I experimented with an electric dehydrator that we got from a garage sale for $5. It was great for drying small plant spices from the garden (marjoram, oregano, etc.), which taste much better than even the bulk spices I buy from our local coop. I also found that dehydrated red peppers make wonderfully tasty snacks when cut in small squares. However, I wasn't happy using a plastic dehydrator, because it wasn't BPA free, and the dehydrator was so small I couldn't really preserve large enough amounts of vegetables to last all Winter. Eventually, I spent the money to buy a much bigger, all stainless steel dehydrator that I've been very happy to put to use.
Using your wood stove to dehydrate: Homesteaders used to hang food above their wood stoves to dehydrate it. See my experiment with dehydrating apples behind our wood stove below.
Solar dehydrators: In some dry climates (unfortunately not mine), people can lay food directly in the sun and it will dehydrate before it rots. In my climate, I would need to a solar dehydrator, which is basically a box with lots of trays and a glass top that lets in the sun so the box heats up. I have experimented with using my solar oven for this, and have sometimes gotten the temperature right so that I have dried herbs rather than burning them, but for anything smaller I find the hanging shelves (that sway) in my type of solar oven too difficult to use. In the future I hope to be able to build a solar dehydrator, with many fixed shelves, and use just the Sun to dehydrate food, so I don't even need electricity.

Sometimes a solar oven (above) can be used as a dehydrator, as long as you can keep it from getting too hot. Below I have the glass top partially covered with a towel so the catnip I'm drying inside doesn't burn.

Notes on how to dehydrate:

I use a reference book (see Resources below) to determine at what temperature and for how long to dehydrate each type of food. My previous dehydrator only worked at one temperature, so I just get checking it to see when the food was dried.
My reference book also helps me tell when the food is done. Some dried foods will be totally brittle (green beans), while others can remain pliable and leathery (apples) when they're done.
A good reference book will also tell you whether or not your food needs any pre-treatment. For example, green beans should be blanched to kill germs before they are put in the dehydrator.
Try to chop the food you want to dehydrate into pieces that are as close to the same size as possible, so they will take the same amount of time to dry and you won't have to pick through them to remove the smaller pieces early. It's not possible to cut everything exactly the same, but do the best you can.
When you lay the food out on the trays, some sources will tell you no pieces should be touching each other. However, I've found that all that is really important is that the food be on a single layer- it should not be in a pile.
Depending on your dehydrator, you may need to rotate the trays during the drying period, so that everything dries evenly.
Pay attention to when you put the food into the dehydrator, so that it doesn't get done in the middle of the night while you're asleep. I find it's best to fill the dehydrator very early in the morning if it can get done before I go to bed, or late in the afternoon so that it can dry overnight.
Once the food is completely dry, I remove it from the trays by tipping the trays into a large bowl. Be careful, or the small pieces of food can fly all over.
I let the food cool off, which usually only takes a few minutes. Then I transfer it to a clean and sterilized mason jar, and screw on the lid. I leave the jar on the counter, out of the Sun, but where I will see it, for a few days so I can check if any condensation collects in the jar. If it does, that's a sure indication that it was not sufficiently dried and should be returned to the dehydrator. I also gently shake the jar each day, to make sure that any moisture gets distributed evenly and there aren't any clumps that have gone moldy hiding in the middle.
Put your dried food into jars right away after it cools. Whenever it is exposed to air, it will start to rehydrate, which will encourage mold.
It's best to use small jars to store dried food, so as little air as possible is left in the jar after you remove some of the food. Exposure to air in the jar will also start to rehydrate the food.
Store the jars in a cupboard out of direct sunlight. If the food stays dry, it will definitely last through the Winter and longer.

Using dehydrated food:

Some dried food is really good eaten just like it is, straight out the jar, for snacks, such as with apples or sweet red peppers.
Other dried foods are best added to a recipe, such as a casserole or stew. These foods, such as green beans and peppers, should be rehydrated before use. I pour boiling water over them and let them soak it up for about 20 minutes before adding the food to my recipe.
If you're cooking soup, you can put the dried foods directly in the pot and let them rehydrate as the soup cooks (such as with dried corn, celery, or onions). Note, however, that you may need to add extra water to the soup because the dried food will soak it up.

Our Electric Dehydrator

I was very happy to buy this all stainless steel dehydrator and get rid of my smaller plastic one because:

I don't need to worry about the harmful effects of heated plastic.
It has twice the dehydrating space as my previous dehydrator.
It has a fan in the back that circulates the heated air evenly, so I don't need to rotate the trays.

This is the all stainless steel dehydrator we bought for $150 in 2020.

It has 8 shelves inside and a catch try on the bottom. Here I'm dehydrating (from top to bottom) red peppers, zuchinni, and cherry tomatoes.

Here we're dehydrating red and orange sweet peppers. These make an amazing snack if you want to eat them straight, or can be rehydrated and added to recipes.

The instrument panel at the top lets you set the dehydrating time, up to 24 hours. It also lets you set the temperature, but it only comes in degrees Celcius, there's no Farenheit option.

Advice on Buying a Dehydrator

I bought my 8 tray dehydrator from Amazon in 2020 for $150. At the time of this writing, the 8 tray version is no longer available.
Below are some (paid) links to a smaller and larger version of what I bought, as well as a link to the general search for all stainless steel machines, so you can see if the 8 tray version is available again.
Be careful when choosing which machine to buy if you want all stainless steel. The first one I ordered turned out to have stainless steel trays, but the rest of the machine was plastic, so I had to return it. In retrospect, it was pretty obvious from the photos that the walls were plastic (they were brown, not silver), but I wasn't paying attention.
Also, be careful of what size you buy. I was disappointed when I opened my current machine to see how small the trays were. Even though I clearly read they were 8x11 inches, the photos of the entire machine looked quite large. I underestimated how much space the fan and heating element would take up. However, it still has twice as much space for drying as my old machine, and I find it is entirely big enough for what I'm trying to do.
What was most important to me in regards to size is that I bought a machine that would fit where I wanted it to on the kitchen counter. My kitchen doesn't really have a space where the larger 10 tray version would have fit.
I am also very happy to have a dehydrator with a fan in the rear that circulates the heat evenly throughout the machine so that I no longer need to rotate the trays. My previous dehydrator didn't have a good fan. It was mostly only a heating element on the bottom that just let the heat rise on it's own, so the top most tray did not dry as fast as the lowest one, and I had to continually move the trays around for even drying.

Search for: All Stainless Steel Dehydrators

All Stainless Steel Dehydrator 6 trays

Commercial Stainless Steel Food Dehydrator 10 trays

Here are some of the jars of food we dehydrated in Summer 2020:

From left to right: peppers, zuchinni, tomatoes, celery.
Small jar in front is lemon peel.

From left to right: green beans, apples, zuchinni.

In our spice cabinet: the four pint jars on the left and middle in the back row are peppers.
The two pint jars on the right in the back are green beans. The two small jars in front are cherry tomatoes.

Resources:

Here's a (paid) link to a great book that is teaching me all about dehydrating:

Making & Using Dried Foods

Why I like this book:

It includes specific instructions for dehydrating each type of fruit, vegetable, and herb, as well as meats, dairy, and grains.
It lists drying temperatures in both Fahrenheit and Celcius.
For each type of food it includes instructions for drying with an electric dehydrator, the oven, or the Sun.
Importantly, it has a section of uses and/or recipes for each dehydrated food that includes personal opinions about which ones taste really good.
It will encourage you to dehydrate things that never occurred to you could be dehydrated, like lemon peel.
If you're handy, it includes instructions on how to build your own electric dehydrator using light bulbs and a fan.

Making & Using Dried Foods
by Phyllis Hobson, 1994
From Storey Publishing

Dehydrating with Our Wood Stove

1. We had some apples in the refrigerator that were past their prime, so I decided to experiment with dehydrating a couple of them. I cored two apples (the corer is the tool in the bottom middle of the photo). You could peel the apples, but since the peel is good for you I wanted to see how it tasted dried. I sliced the apples into a variety of thicknesses, all less than 1/4", to see what would dry well. I did not pretreat the rings in any way to discourage browning.

2. I hung the apple slices on the dowel we recently built behind our wood stove for drying socks (see the Laundry section). Note I used a dowel that had not been stained, because it seems like the wet apples could soak up the probably toxic stain. If you don't have a dowel to use, it's traditional to just hang the apple rings on a string above the stove.

3. Apple slices when first hung up.

5. All the slices are beginning to dry. I left them hanging for about a day and a half (note that our small stove wasn't burning during the night when we weren't awake to add fuel).

7. I stored the rings in a mason jar, and kept an eye on it for a day or two to see if any condensation collected in the jar, which would be a sure indication that they were not sufficiently dried. I don't know how long they would have lasted in storage because they were such a wonderful snack (including the peel) that I ate them all the next day at work.

4. The thinnest slices started to dry first- they are curling.

6. Close up of dried apple rings. They do not get crispy. There shouldn't be any moisture inside when you rip one open, but they'll still be a bit supple and leathery.

This was a very successful experiment. This method is great for late Fall apples. However, I realized that unlike our ancestors, we aren't normally using our wood stove during the Summer, when most of the food I want to dehydrate is fresh (like peppers and tomatoes), so I use my electric dehydrator during the Summer.