Dehydrators are an invaluable tool for preserving homegrown foods. There is a dazzling array of products available on the market, which can make purchasing a dehydrating unit confusing. However, knowing a little about how dehydrators work, some different types, and how you want to use your dehydrator makes sorting through the information a bit easier.
Most dehydrators work by utilizing heated air and distributing it with a fan into an enclosed space to dry food. Although they can differ in size, power, and design, all dehydrators (aside from solar dehydrators) have a fan and screen-style trays or shelves that allow air to circulate around the food placed inside. Many also have thermostats to control the air temperature if desired.
There are basically two types of dehydrator design: vertical-airflow and horizontal-airflow. Vertical-airflow dehydrators have a fan either in the top of the unit or in the bottom. This type of dehydrator has trays that stack on top of one another inside the unit. Food closest to the fan dries faster, so shuffling trays during the drying process may be necessary to ensure even drying. Units that have the fan mounted in the bottom are considered more efficient because heat rises. However, food may drip onto the fan causing a bit of a mess and difficult cleanup.
Another drawback to the vertical-airflow design, if you are drying different foods at the same time, there’s a chance of imparting varying flavors to the foods being dehydrated as the fan pushes the air from one shelf of food to the next. Most vertical-airflow dehydrators have the capability to expand as trays are stacked upon one another. Some of the “deluxe” models of vertical-airflow dehydrators do not have these issues. The fans in these models are covered to prevent food from spilling onto them. In addition, special ducts help distribute air more evenly. This eliminates the need to rotate trays during the drying process, and keeps food flavors from blending.
The tray design in these units can make food placement difficult, as there is a channel that extends through the center of each tray. This reduces the overall surface area available and can make laying out strips of food such as jerky a bit tricky.
Vertical-airflow dehydrators have the capability to expand simply by adding more trays to the stack. Different models have different limits, but for the purposes of most households, they should have plenty of room. Lower priced models may have five trays, which is about 5 cubic feet of drying space. The stackable trays are easy to store and are usually small enough to fit in a standard size dishwasher or kitchen sink for cleanup.
Horizontal-airflow dehydrators will have a fan or other primary drying element situated at the back of the unit. They look similar to a microwave in their boxy shape, and some have a pull-type door on the front. Air is evenly distributed to all the food inside the unit because the air flows evenly across the trays. It is easy to check the progress of foods because the trays slide in and out of the unit much like the shelf in an oven. Trays can also be removed to accommodate taller items. In addition, there are stainless steel models available that help eliminate the possibility of chemicals leaching into food from the plastic trays, if that is something you are concerned about.
Horizontal units are often larger than vertical-airflow dehydrators, which translates to taking up more storage or counter space. The sliding shelf design limits the unit’s capability to expand only to the number of shelf slots it already has. In addition, some of the shelves are too large to fit into a kitchen sink or dishwasher, making it a little more challenging to clean.
Solar food dehydrators are also very efficient, as they require no electrical power and instead use the sun’s energy to dry your foods. You can either purchase or build one using designs that are easy to find online. Take a look at a few of the designs from our sister publication Mother Earth News at http://bit.ly/1UMi8cuandhttp://bit.ly/1UMhWdk.
Temperature control
If you plan to make jerky with your dehydrator, a model with temperature control is a must. Research has shown that the old method of drying meat at low temperatures for a long period of time is not safe. Pathogens such as Salmonella and E. coli O157:H7 will not be killed unless the jerky is heated to a high enough temperature.
Make sure the dehydrator you select for making jerky will maintain at least 145 to 155 Fahrenheit. You can test this by placing a dial stem thermometer near the center inside a unit without any food inside, and have at least three trays in place in a stacking unit. Turn the unit on, and set the temperature to 155 Fahrenheit. Close the unit, and check it after the temperature has stabilized. Meat should be dried for at least 4 hours.
If you do not have a dehydrator that will reach the correct temperatures, never fear. Jerky may still be safely prepared in a dehydrator by preparing meat ahead of time, either steaming or roasting to an internal temperature of 160 Fahrenheit (165 F for poultry). You can boil strips of meat in marinade or water for about 5 minutes prior to dehydrating. Note: This will produce jerky that is drier than and not as chewy as jerky dried entirely at the proper temperature.
Marinades and spices will also help kill pathogens. Marinate meat in the refrigerator in a sealed container with a plate or bowl beneath it to catch drips. Never dry jerky at the same time as fruits or vegetables. The higher temperatures will dry fruits and vegetables out too much, and there is risk of contamination.
Cleaning and care
Dehydrators are relatively easy to clean and care for. The trays are easy to remove, are lightweight, and can be placed in a sink or tub to wash. Washing trays with hot soapy water will remove most food residue, and the trays of some models can be put in the dishwasher on the top shelf. It is not recommended to run trays through a heated dry cycle. For stubborn stuck-on food, soak trays overnight in soapy water. The following day, sprinkle trays with a non-abrasive cleanser and scrub with a non-abrasive scrubber. Powdered brewery wash, available wherever brewery supplies are sold, is an excellent cleanser for removing tough stuck-on foods. A toothbrush is also helpful to remove particles trapped in the screens.
Prevention is best, so to avoid scrubbing trays altogether, try using a non-stick sheet on each tray. Parchment paper or silicone mats may be used for some items, but it does not work very well in vertical-airflow units because it impedes air flow. Many manufacturers make special non-stick sheets to use on their dehydrator trays. It is not recommended to spray any kind of non-stick spray or to use any kind of oil on dehydrator trays – the oils may adhere to the trays and build up over time. In addition, some of the oil is transferred to the dehydrated food and can impart flavors and shorten shelf life.
Tips and tricks
There are a few ways to ensure you produce high-quality dehydrated foods. Fruits and vegetables should always be of highest quality possible. Be sure to carefully wash them and remove excess water before placing on drying trays. Fruits such as apples and bananas and vegetables such as potatoes will turn brown during drying. To prevent this, soak slices in a high ascorbic acid content fruit juice such as lemon or pineapple. Commercially produced ascorbic acid (found with the canning supplies in stores) can also be used. Let the slices soak for about five minutes, then rinse with clean water and place on paper towels to remove excess water.
Be sure to follow recommended drying guidelines that come with your dehydrator. Most dehydrators come with a book that outlines thickness of slices, drying times, and optimal temperature settings for different foods. Don’t overload trays, and opt for larger batches of the same food item to dry at once rather than several different kinds of foods to be dried together. This will help ensure the best flavor and drying efficiency.
If possible, slice fruit and vegetable items between 1⁄4 and 1⁄2 inch thickness, and try to keep them uniform so the pieces dry evenly. Don’t overlap slices, and don’t let slices touch one another on the trays. Note that food will shrink during the drying process, so if you happen to dry something small such as corn, be sure the screens they are placed on are small enough to keep the dried pieces from falling through.
When selecting meat for dehydration, be sure to choose lean meats or trim all excess fat from meat strips. For chewier jerky, slice meat with the grain. Partially freeze meat to make it easier to slice, and cut slices no thicker than 1/4 inch. If you are using ground meat to dehydrate, 93 percent lean or more is best.
Reduce food waste by dehydrating leftovers. Vegetables, fruits, soups, and sauces can be dehydrated, which will help prevent waste and save on prep time later. It is not recommended to dehydrate dishes with meat in them, however.
Have some fun with your dehydrator. Unless otherwise stated in your user manual, many dehydrators may be used to do things other than dry food. Try using it to start food cultures such as yogurt or kombucha. Craft projects such as air-dry clay, paper machè, flowers, and craft paper can be fun rainy day activities for youngsters. It also works well for raising bread dough and making herbal teas.
A dehydrator can be an invaluable and fun addition to your kitchen. Properly dehydrated foods have an extended shelf life, can save on storage space, and do not lose their nutritional value. They can simplify meal preparation and save money. Make the most of your hard work during the harvest, and extend the fabulous flavors of fresh homegrown food.
Web Pointer: Try your hand at making homemade jerky and other dehydrated snacks (http://bit.ly/1Fs483J).
Jackie is a registered nurse living in the Flint Hills of rural Wabaunsee County, Kansas. She and her daughter Kate run a small farm with a host of horses, cows, sheep, dogs, chickens, ducks, cats, a rabbit and a donkey. She enjoys writing, cooking, learning about natural medicine, and most anything to do with animals.