Dehydrating 101

[HOMEGROWN.org]

The following 101, on dehydrating basics, comes from HOMEGROWN member Dr. John, a federal civil servant turned home brewer, gardener, putter upper, and founder of the South Carolina food-security group Aiken Localvore. Thanks for lending your know-how, John, and please keep the good ideas cooking!

 

Dehydrating food for storage goes back through time immemorial. It’s one of the oldest and simplest methods of food preservation there is, and it still holds up, even with more advanced options available. The biggest problem most folks have with dehydrating is fear of the unknown: Did I use the right temperature? Did I over- or underdry the food? This 101 will help beginner dehydrators safely and successfully dry their food bounty without major investments in money or effort.

 

WHAT IS DEHYDRATION

It all started with hunters using sunlight to do their cooking. Simply, dehydration uses heat to withdraw moisture from food and circulated air to absorb and remove that released moisture. The benefit of dehydration is that, when properly dried, food can last for months without refrigeration or freezing—as useful for trail hikers today as it was for our forebears.

 

Dehydrating food lets the home cook preserve large amounts of food using little space, and although I recommend using a commercial dehydrator, dehydrated food requires no additional equipment to maintain the products once they’re dried. Home drying local fruits, vegetables, and meats is more energy efficient than canning or freezing and is less expensive than buying store-bought dehydrated items. And for those are on special regimens, such as the raw diet, dehydration at low temperatures does not kill or cause deterioration of the enzymes in food, unlike other preservation techniques. And dehydrated food tastes good, too!

 

WHY DEHYDRATE?

• Extend the life of your groceries.

• Preserve your harvest in summer, when you’ve got more than you know what to do with, for use later, when you’re longing for tomatoes and peppers.

• Save money! Factoring in the cost of all ingredients and electricity used, I calculated that I would save $102 by making my own 5-pound batch of beef jerky rather than buying it prepared. Here's a chart.

 

WHAT TO DEHYDRATE

• Make dried vegetables to use as flavor enhancers in soups and stews.

• Make your own potato chips! See below.

• Dry fruits for for use in baking, or as a topping for yogurt and more.

• Make healthy, long-lasting snacks—from meat, fruit, and more—without preservatives.

• Make treats for your pets.

• Dry grains and fresh pasta.

• Dry craft items and sell them for extra income.

 

CHOOSING A DEHYDRATOR

Even for newbies, if you think you’ll be dehydrating with some frequency, I highly recommend purchasing a dehydrator rather than relying on solar or oven techniques. A few questions to help guide you in selecting a dehydrator:

 

1. SOLAR DEHYDRATORS (COMMERCIAL OR HOMEMADE): Solar dehydrators use the sun as their heat source to extract moisture and natural air convection to remove it. These are the least expensive, considering sunlight is free. I have the plans for making and using a homemade solar dehydrator, and I’ll post the outcome in an upcoming 101.

Pros: Simplest means of dehydrating. A solar dehydrator requires no electricity. It can be made at home and scaled to your desired size using screens and excess wood. Building one could be a great family project.

Cons: Food needs two to four full days of sunlight to dry and requires covering the food to protect it from bugs and critters.

 

2. CONVENTIONAL OVEN: Using your existing oven is a possibility, but it’s not efficient to run your oven frequently for many hours at a time. In addition, your oven’s thermostat might not go low enough to dry many items (some recipes call for as low as 100F) and might cook the food instead. You’ll also need a means to circulate the air in order to remove the moisture. Convection ovens would work since they have internal fans, but the temperature range could still be an issue.

Pros: If you’ve got a kitchen, chances are you’ve got an oven.

Cons: The temperature range might not go low enough; requires an external source of air circulation; uses lots of electricity; heats up the whole kitchen.

 

3. COMMERCIAL HOME DEHYDRATOR: Using a commercial home dehydrator is probably the easiest and most cost effective way to dry food, especially for newbies. The setup is designed for maximum efficiency; the temperature may be controllable; and the devices are easy to clean.

Pros: Readily available and inexpensive. Temperature and air circulation is built in. Trays allow for maximum air circulation. 

Cons: Takes up kitchen and storage space; not all models include thermostats; uses electricity; increases kitchen humidity.

 

As with any appliance, there are many different manufacturers, models, styles, and options. Let’s make this simple and look at the three essentials for a home dehydrator and two nonessential considerations.

• ESSENTIAL #1: Fits your budget. You can purchase a dehydrator with lots of bells and whistles and price tags in the thousands to match. Why? Do you really need those features? Keep it simple, inexpensive, useful, and fun.

• ESSENTIAL #2: Includes a controllable thermostat. Dehydrators that allow you to control the temperature offer greater flexibility. They let you dehydrate food at a higher temp, which lets you dry things like jerky without needing to finish it in the oven. They also let you dehydrate cooler than you could at a fixed temp, which works better for fragile items like herbs that otherwise can turn brown and lose their flavor. They give you precise temp control, usually between 105 and 158 degrees. One note: The thermostat reading refers to the temperature of the food you’re drying, not to the air temperature inside the dehydrator.

• ESSENTIAL #3: Is expandable. Most dehydrators will come with a few drying trays, but chances are, the more experienced you get, the more space you’ll want. For example, the Nesco FD-60 comes with four drying trays but can fit an additional eight (available separately). There are regular drying trays (think jerky or fish), special fruit trays (apple slices), and small-item inserts (grains). For example, I’ve got 12 regular drying trays that I use year-round; four fruit trays that I use primarily in the spring, summer, and fall to dry fruit for leathers and sauces; and six small-item inserts that I use primarily in the summer, fall, and winter to dry seeds and herbs.

• NONESSENTIAL #1: A timer. In my humble opinion, a timer isn’t essential since most kitchens are equipped with clocks. But because dehydrating can take up to 24 hours, you might want a dedicated timer that won’t get interrupted by other cooking or baking projects.

• NONESSENTIAL #2: Size. This one’s more of a point to ponder. Dehydrator footprints vary greatly from manufacturer to manufacturer. Some are box shaped while others are round. I use a circular style only because that’s what I started with. Square or round, it’s a personal choice.

 

My personal recommendation? (And nope, I’m not getting a kickback.) If you want a round dehydrator, go with the Nesco FD-60. If you want a square style, go with Excalibur 3900. Both receive very high ratings.

 

OTHER USEFUL TOOLS TO HAVE ON HAND

The only things you absolutely need are your food, the dehydrator, and its trays. The items below are simply suggestions that might make your dehydrating projects easier.

 

• Mandoline

• Peeler/grater

• Apple corer

• Offset bench scraper or icing spatula. This is used to smooth the fruit or yogurt leathers to an even depth in the tray. It also comes in handy when removing dried items from the trays.

• Nylon scrub brush and a mild dishwashing soap to clean the trays

• Assorted knives to peel, trim, and slice

• Deep steamer (I use a crab steamer) outfitted with a tray to steam or blanch food

• Slotted spoons to remove items from the blanching pot

• Dedicated timer

• First-aid kit with bandages and medical tape. I always manage to ding my fingertips with a knife or the mandoline, even when using the slider. I’m up to two cuts this month.

• Patience, patience, and more patience. As with smoking, canning, and freezing, the devil is in the prep. More on that below.

 

FOOD PREPARATION

Preparation isn’t much different than what you’d do when canning or freezing. Always start with clean, safe food products handled in a clean work environment. I do purchase the seconds that our farmers can’t sell to the public because they aren’t pretty enough. All I do is trim out the blemished areas and prepare them according to the given recipe. A few helpful hints:

 

1. Some items require blanching or marinating prior to dehydrating. Hard vegetables like potatoes require blanching so that you can slice and dry them evenly (otherwise, a dehydrated potato would be as hard as a rock), while meat requires marinating to add flavor, acid, and salt.

 

2. Watch how thick you slice your food. As I found out, potatoes for dehydrated chips should be sliced very thin, while green peppers and tomatoes can be up to 1/4” thick. When in doubt, err thinner.

 

3. Don’t crowd or overlap food on the trays. Leave a little space between items so that air can circulate. I have extra trays that I don’t use for every dehydrating project, but they come in handy when I want to spread out the produce.

 

4. Coat your trays lightly with cooking oil to prevent sticking. There is nothing more frustrating than scrubbing rock-hard peppers or cucumbers off of a tray!

 

DEHYRDATOR RECIPES

The most important advice I can share? Follow a recipe and use common sense. Dehydrating is a simple process. Don’t make it more complicated!

 

1. DEHYDRATOR POTATO CHIPS

Prep time: 20 minutes

Cook time: 4 to 5 hours (or more, depending on local temperature and humidity)

 

WHAT YOU’LL NEED

» Deep pot for blanching

» Vegetable peeler                           

» Knife or mandoline

» 2 to 3 pounds of baking potatoes

» Olive-oil spray or olive oil and a basting brush

» 1 cup apple cider vinegar

» ½ cup salt

» Bowl for ice bath

» Ice

 

WHAT TO DO

1. Fill the pot with water, add salt and vinegar, and bring to a boil.

2. Peel potatoes (if desired) and add to pot.

3. Blanch potatoes in boiling water for 5 to 7 minutes.

4. Transfer potatoes to an ice bath to stop the cooking process. When the potatoes are cool to the touch, transfer them from the ice bath to a paper towel. Blot dry.

5. Slice the potatoes horizontally, as thinly as possible. A mandoline works well for this.

6. Lightly spray or brush the dehydrator trays with oil to prevent sticking.

7. Ditto the potato slices. Season to taste.

8. Stack the filled trays in the dehydrator.

9. Continue spraying, filling, and stacking until you’ve used all the potatoes.

10. Set the dehydrator temperature to 95 degrees.

11. Dehydrate for 4 to 8 hours or until the potatoes have reached a leatherlike consistency and are no longer sticky.

12. Remove the potatoes while they’re still warm, let them cool completely, and store them in a well-sealed container in a dark, dry, cool place. I keep mine in a resealable bag. Transparent bags and clear glass jars are useful because you can see any accumulated moisture—your enemy. Generally my chips don’t last more than 2 to 3 days before we’ve eaten them up, although they should keep for several months. According to the National Center for Food Preservation: “Because food quality is affected by heat, the storage temperature helps determine the length of storage; the higher the temperature, the shorter the storage time. Most dried fruits can be stored for 1 year at 60F, 6 months at 80F. Vegetables have about half the shelf-life of fruits.” If they look or smell moldy, dispose of them.  

 

2. YOGURT LEATHER                                                                     

Prep time: 10 minutes

Cook time: 4 to 5 hours (or more, depending on local temperature and humidity)

 

WHAT YOU’LL NEED

» 16 oz Greek yogurt (your choice of flavor or make your own)

» Solid trays

» Offset spatula

» Olive-oil spray or olive oil and a basting brush

WHAT TO DO

1. Lightly spray or brush the fruit trays with oil to prevent sticking.

2. Pour the yogurt onto the trays. Using your spatula, smooth it to a depth of 1/8” or just below the tray edge.

3. Stack the filled trays in the dehydrator.

4. Continue spraying trays, filling, leveling, and stacking until you have used up all of the yogurt.

5. Set the dehydrator temperature to 135 degrees.

6. Dehydrate for 4 to 8 hours or until the yogurt reaches a leatherlike consistency and is no longer sticky.

7. Remove the yogurt leather from the dehydrator while still warm. Let it cool completely then roll it and store it in a well-sealed container in a dark, dry, cool place. I keep mine in a Pyrex container in the fridge. We eat this so quickly it doesn’t last long around my house. If your leather isn’t gone in a few days, roll it, wrap it tightly, and store it in the freezer.

3. FRUIT LEATHER

Prep time: 60 minutes

Cook time: 4 to 8 hours

WHAT YOU’LL NEED

» 2 cups frozen or fresh fruit of your choice (I use mixed fruits)

» Solid trays

» Offset spatula

» Olive-oil spray or olive oil and a basting brush

 

WHAT TO DO

1. If you’re using frozen fruit, let it thaw completely. Your blender will thank you.

2. While the fruit is thawing, spray or brush your trays with oil.

3. Put the thawed or fresh fruit in a blender or food processor and purée until smooth.
Carefully pour the purée onto your solid tray. Using your spatula, gently spread the mixture evenly over the tray.

4. Stack the trays in the dehydrator.

5. Continue spraying trays, filling, leveling, and stacking until you have used all of the mixture.

6. Set the dehydrator temperature to 135 degrees.

7. Dehydrate 4 to 8 hours or until the fruit has reached a leatherlike consistency and is no longer sticky.

8. Remove the fruit leather from the dehydrator while still warm. Let it cool completely then roll it and store it in a dark, dry, cool place. I keep mine in a Pyrex container in the fridge. According to the NCHFP, fruit leather “will keep up to 1 month at room temperature. For storage up to 1 year, place tightly wrapped rolls in the freezer." 

 

4. BEEF JERKY

You can make your own marinade from scratch, you can use an off-the-shelf liquid marinade, or you can mix up a marinade using a seasoning packet. But whatever you do, when making homemade beef jerky in the dehydrator, you need to start with a marinade. Be sure to follow your marinade’s instructions, especially when using a cure.

Prep time: 20 minutes

Marinate: 4 to 12 hours

Cook time: 4 to 5 hours

WHAT YOU’LL NEED

» Nonreactive bowl to contain the marinade

» Measuring cups and spoons

» Sharp knives

» Good cutting surface

» Sealable gallon bags to hold the meat while marinating

» 1 ½ to 2 pounds of grass-fed flank steak, round steak, brisket, rump roast, etc. (I’ve had great success with all of the routine cuts of beef. It’s a matter of removing the excess fat.)

» Marinade; see recipe below for a homemade version

 

WHAT TO DO

1. Working along the grain, cut the meat into 1/8”-thick strips. Remove excess fat and gristle.

2. Choose your own adventure: If you’re using a premade marinade, go to step 4. If you’re using a commercial dry mix, prepare according to the instructions then go to step 3. If you’re preparing your own marinade, mix it up (see recipe below) then go to step 3.

3. Pour your marinade into a small nonreactive bowl and stir well.

4. Place the meat in a gallon-size plastic bag. Pour the marinade on top of the meat then seal the bag closed.

5. Massage until the marinade completely coats the meat. Place the sealed bag in the refrigerator for a minimum of 3 hours and up to 24 hours. I marinate overnight for a deeper flavor.

6. Remove the meat from the marinade and place it on a paper towel. Blot dry.

7. Lightly spray the regular dehydrator trays with oil.

8. Line the meat on the trays, being careful not to overlap or crowd the pieces. Use more trays or make a second batch if you’re short on space.

9. Set the dehydrator temperature to 165 degrees or to the “meat” setting.

10. Six to 12 hours later, you will have the best beef jerky you’ve ever eaten! Properly dehydrated jerky should register 165 degrees on a meat thermometer. (Remove a piece of jerky from the dehydrator before checking the temp. Finished jerky should bend but not snap.)

11. Store your beef jerky in an airtight container and grab a few slices when you need a quick snack. The jerky should keep for roughly 2 weeks at room temp; you can refrigerate or freeze it for a longer shelf life. (Here’s more on jerky from the NCHFP and from Colorado State.) If you have any questions, feel free to leave them in the comments section below, and I’ll respond.

 

MARINADE FOR BEEF JERKY: Mix all ingredients in a nonreactive bowl until well combined.

» 2/3 cup soy or shoyu sauce (Low-salt versions are acceptable for sodium-restricted diets, but meat may mold faster due to moisture buildup.)

» 1 to 2 Tbsp hot sauce or sriracha

» 1 Tbsp agave nectar

» 3 tsp garlic powder

» 3 tsp onion powder

» 2 tsp crushed red pepper

» 2 tsp black pepper

» 1 tsp paprika

» Scant ¼ tsp of Prague Powder or curing salt

» 1 Tbsp liquid smoke (optional)

 

MORE SOURCES FOR DEHYDRATOR RECIPES

Most dehydrators come with an instruction booklet containing simple recipes you can try as soon as your dehydrator is out of the box. For more suggestions, check out the manufacturer’s website, customer blogs, and downloadable operator (see below).

 

As for books, there are a slew of them out there. My favorite is Making & Using Dried Foods, by Phyllis Hobson. Hobson presents all of the info necessary to safely prepare food using dehydrators, solar dehydrators, conventional ovens, microwaves, and even homemade dehydrators (including plans for building your own) and specifics on dehydrating a wide assortment of fruit, veggies, meat, dairy, and more. This is definitely one to add to your library, and it’s available electronically as an ebook.

 

Here on HOMEGROWN, there’s also:

 

• Cynthia’s slideshow Dehydrator Fun and blog post on dehydrating peppers

• My recipe for salt & vinegar kale chips

• Tips on drying peaches

• Got more recipes to share? Post a comment below!

 

And some of my go-to sources online for dehydrator recipes and general information include:

• Living and Raw Foods

• NESCO Adjustable Dehydrator Owner’s Manual (downloadable PDF)

• NESCO How To Guides

• National Center for Home Food Preservation, University of Georgia (a great reference that I use a lot)

RECAP: THE MOST HELPFUL HINTS

• Dehydrating is simply using heat and air to extract and remove moisture from a product.

• Properly prepare the food you’re going to dry: Blanch, marinate, and/or thinly slice as recommended in your recipe. And yep, use a recipe. This isn’t rocket science—but it is science.

• That said, expect some variations in time and temperature. Experiment once you’ve got the hang of things.

• Simple is better. Dehydrating is as old as time itself. In other words, you don’t need lots of bells and whistles when buying a dehydrator. If you’re hot to trot to spend money, buy more produce and additional trays.

• Make sure you have enough drying space. You don’t want to crowd or overlap the food you are drying.

• Buy the right types and number of trays for your needs. If you’ll be making fruit leather, buy the roll inserts (also good for dehydrating sauces). If you’re dehydrating small items, such as herbs and seeds, buy the small-food inserts.

• Properly store your food once it’s dehydrated. Use tight-fitting lids and bags that seal closed. Always fill containers to the maximum—packing individual-use servings, if necessary—in order to reduce dehydrated food’s exposure to air and moisture. Each time you open a bag or a jar, you expose your precious goodies to moisture. Read more about individual dry times and storage on the National Center for Home Food Preservation’s website.

• Have fun! Get the kids involved. Once you’ve done the knifework, dehydrating is very safe and easier than canning.

 

SPEAK UP!

Got a question for Dr. John? Or another dehydrating resource to suggest? Post it below and keep the conversation rolling. You might also be interested in freezing, drying, and storing herbs; solar cooking and baking; drying chili peppers; rendering lard; making pectin; preserving apples; and making your own fermented chili paste, and you might consider joining the food preservation group. Don’t miss Dr. John’s other 101s, on container gardening and creating a bucket brigade. You can always find more things to cook, preserve, make, craft, plant, grow, and dry in the HOMEGROWN 101 library.

PHOTOS: (FRUIT AND NUTS) BLACK CAT COTTAGE; (GRAPEFRUIT, CITRUS PEEL, TOMATOES, PEPPERS) CYNTHIA; (FIGS) PAT; (TEMPERATURE, POTATOES, YOGURT LEATHER) JOHN

 

[Joe Klinkhoff]

Great 101 Dr. John!  I also love to dehydrate.  I still have about 1/2 lb of crushed hot peppers from two years ago.  We call it powdered lava and only a finger nail size amount heats chili and soup well above where it should be.  Also, I cannot stand the smell of a tomato but love to cut romas in to 8ths and turn them into "sun-dried" tomatoes..thanks again for the good info.  will be checking those two dehydrators out as I am in need of a new one.  Also never thought to spray or coat the trays with oil for non stick....also love love love home made beef jerky!!

[John F. Houpt II, PhD]

Thanks for the compliment Joe.  I was just an information source. Jennifer did the hard work.  Im looking forward to making your hot sauce and dehydrating it for use as a rub for making smoked fish and jerky and as a seasoning for my Low Country Boil.  If you have any dehydrating recipes or ideas, please post them. 

[Joe Klinkhoff]

That sounds awesome, never thought of drying it after fermenting it!!  And a rub, that will be some hot food.  I made a pork stir fry on wednesday night and added about half teaspoon to the entire stir fry vegetables, noodles and meat and it added some real heat!  Had the dog licking his chops for a few minutes!!

[Kathy La Plante]

Hi Dr. John. Thanks for this information! I am a civil servant and am getting ready to retire in 2015, move back to our SW home in New Mexico and begin a new chapter in my life. This kind of stuff is exactly what I want to learn how to do. How did you get started? Did you just have the desire and then jumped in or did you take classes etc.? I am new to this web-community and am learning so much already. Thanks again and I look forward to hearing more from you.

[John F. Houpt II, PhD]

Kathy, guess I always had the desire to be independent as I could be. Being a son of parents and grandson of grand parents living during the depression and WWII. I was always taught to take care of yourself and family, and be grateful for what you have. Now I can enjoy the lifestyle of not being tied to all the fluff of society and make, grow, and put up my foods and pursue activities the folks did during the depression and on the farms. As for classes, not a one besides those I teach on these subjects. I am a voracious reader and am not shy asking questions of the folks I want to learn from. Guess I'm a forever student and hippie minded person. LOL!