Basic tips before you start
Blanching and skin scalding
Blueberry tips
Can you over dry your food?
Case hardening
Cheese, milk, butter, eggs
Choosing flour
Cooking with dried beans
Dehydration vs. bacteria
Dehydrators: Which one to choose?
Drying times
Food that should be steamed before dehydrating
Foods requiring no prep
Frozen fruits and vegetables
Fruit roll-up tips
Fruit skins
Fruit tips
Herbal tea tips
Herbs
Honey
How dehydrated should my food be?
Lemon juice
Longer time and lower temperature
Make bread rise with a dehydrator
Meats
Nutrients and vitamins
Onions and garlic
Plums
Potatoes
Powdered fruits and vegetables
Rehydrating dehydrated foods
Rehydration by Refrigeration
Shelf Life of Dehydrated Foods
Steamer/juicer marble trick
Stop small foods from falling between the trays
Tomato paste and tomato sauce roll-ups
Vegetables
What CAN’T be dehydrated?
Wheat: Milled or not?
When to salt
Why dehydrate?
Yogurt
Avocados
Avocados have very high oil content and therefore are not recommended for dehydration. They will not store well and will turn rancid after a period of time.
Basic tips before you start
Click here for a PDF document with some important beginner tips and information for dehydration and storage! You can view the document, save it to your computer, or print it out!
Here are some additional tips:
Wash Everything Down: Use an anti-bacterial cleanser of your choice. Just like when canning foods, it is important to practice good hygiene while dehydrating as well. This ensures a good end product with a longer shelf life.
Wear Latex or Vinyl Gloves: There is natural oil and moisture in your hands, which will contaminate your foods by reintroducing moisture. Cheap “disposable” gloves like these are convenient, but you can also reuse them so they will last longer!
Warm Up Your Dehydrator: Air circulation helps for an evenly dried product and eliminates the growth of contaminates, therefore it is best to start the dehydrator and get the air moving before introducing your food
Try Scissors: It is much easier to cut dehydrated foods with kitchen scissors than a knife! Some dehydrated foods you can simply crumble in your hands.
Use Stainless Steel: If you use a knife that is not stainless steel to cut certain items, such as bananas, the final product will appear browner in color. These are still fine to eat, only less appealing.
Blanching and skin scalding
Blanching is when you place your food in boiling water for about 30-60 seconds prior to dehydrating.
Why do you have to steam or blanch some items and not others?
Skin scalding occurs during the blanching process. Skin scalding is done to soften the skin of a fruit or vegetable to help the escape of moisture, or help the removal of the skin. While blanching a grape, for example, you must blanch it prior to dehydrating in order to soften the skin for better moisture removal. While blanching a tomato or peach, however, you blanch to allow for easy skin removal: you will find they just fall right off!
Food that should be blanched or skin scalded:
- Grapes
- Tomatoes
- Blueberries
- Plums
- Cherries
- Peaches
- Cranberries
- Pears
- Summer squash
- Zucchini
Dehydrating Blueberry tips
Place blueberries in a pot of boiling water for about one minute. Next, add cold water to the boiling pot, then place the dehydrator tray across the sink and pour on the blueberries, like a strainer. The less you have to move them around the better. Next, the secret is to prick each berry with a toothpick to let the air out. Dehydrate at 125°F. for about 18 hours. If some blueberries are still large and soft, they are not fully dehydrated. Puncture another hole in those ones, and place back into the dehydrator for 3-6 for hours.
INSTRUCTIONAL VIDEO
Can you over dry your food?
No, you cannot over dry. Instead, the true concern should be under drying, as leaving moisture in your food can cause it to spoil. But, if you remove 95% or more of the moisture from your food and store properly your food will last for years and taste great. Therefore, if you are unsure if your food is dry, keeping it in the dehydrator longer will not hurt.
Case Hardening
Case hardening occurs when the temperature is too high, causing the food to harden on the outside and the moisture to remain on the inside. When this happens the moisture will spoil the food over time, and it will need to be thrown away. You will know you have case hardening from the appearance; the outer case of the food will be clear, and the inside will be dark or black.
Avoiding case hardening is a must for successful long-term storage. A lot of people recommend 135°F for fruits and 125°F for vegetables when dehydrating. It has been our experience that 120-125°F. is the best temperature for both fruits and vegetables. Longer time with lower temperature is the best method to prevent case hardening. If you get case hardening, try dehydrating at a lower temperature for a longer duration the next time.
Can you fix case hardening?
If you have case hardening you sometimes can turn it around. To do this, cut the pieces in half or put a slit in the top of the food and put back in the dehydrator, this allows the trapped moisture to escape. For sliced potatoes, simply poke them with a sharp knife and place them back into the dehydrator. Small cubed potatoes are too difficult to correct, so simply cook them and eat them before they spoil. They are still good to eat you just do not want to store them long term.
Cheese, milk, butter, eggs
Cheese, milk, eggs, and butter need to be commercially processed with special equipment. Items with high oil content must also be processed using special commercial methods and will turn rancid in a short period of time if done incorrectly. It has been recommended by experts in food storage and dehydrating that these items be purchased through a company that can commercially process such items.
Eggs, however, can be scrambled and dehydrated and then rehydrated with boiling water, but you cannot use these dehydrated scrambled eggs in cakes, breads, or other baked goods. The shelf life when done at home is not as long as if purchased by a company. Dehydrated scramble eggs are great for hiking or camping. My advice is to buy powdered eggs that have been safely dehydrated by commercial equipment and properly stored. They taste great (like a fresh egg), and are more versatile for cooking, and are safe. The same goes for cheese, butter and milk.
Choosing flour
Whole Wheat Berries: This flour can be stored for 30+ years in the berry form if held in an airtight container with a good rubber seal and a 2000cc oxygen pack for each 5-gallon volume of wheat. However, once ground, whole-wheat flour should be stored in the refrigerator or freezer in an airtight container until it is ready to use. “Hard” berries such as hard red winter, hard white winter, hard white spring, or hard red spring indicate that it is wheat with a high protein level (14%). This wheat is great for breads. However, soft wheat such as all-purpose flour and cake flour contains less protein (10-12%) and is great for cakes and pastries.
Unbleached Flour: Flour that is whitened using oxygen (has more of an off-white appearance).
Bleached Flour: Flour that is processed with chlorine. The chlorine, however, evaporates after processing. Processing the flour helps reduce contamination and improves the shelf life (2-5 years if stored properly). Bleached and unbleached flour are virtually the same.
Enriched Flour: Flour that is supplemented with iron and four B Vitamins (thiamin, niacin, riboflavin and folic acid) to replace what was removed from the bran and germ. In addition, calcium is supplemented. There is no change in taste, color, texture, baking quality, or caloric value of the enriched flour.
Pre-Sifted Flour: Flour that is sifted at the mill, making it unnecessary to sift before measuring. However, when your flour is vacuum packed and stored for a long period of time it is always a good idea to sift it again, regardless if it had been sifted previously.
Whole Grain Flour: Flour that contains the germ, bran, and endosperm of the wheat kernel. Diets rich in whole grains reduce the risks of obesity, diabetes and heart conditions.
Cake Flour: This flour is lower in protein, lighter, fluffier, and is used for cakes, pastries, and muffins. Almost all cake flour is bleached. Bleach toughens the molecules allowing the flour to carry more sugar and fat. This flour can be purchased in the bake goods section of your grocery store. Or, you can prepare your own by taking 1 cup of all-purpose flour and removing 2 tablespoons of the flour and replacing it with 2 tablespoons of cornstarch. If you want it to be self-raising then add a pinch of salt and 1 ½ teaspoons of baking powder to the mix. Write these measurements down and tape it to the back of your flour canister.
Organic Flour: This flour is chemical free. It is grown and stored without the use of synthetic herbicides or insecticides. It also means that no toxic fumigants were used to kill pests in the grain and no preservatives were added to the flour, packaging or food product. Organic flour, however, is not standardized, so its definition varies from state to state.
Cooking with dried beans
Dried beans are great to use in your pre-packaged foods. Meals containing dried beans will need to be prepared with a slow cooker (crock-pot). This is because beans take much longer than noodles or barley to rehydrate and cook. I recommend using a crock-pot with all soups. The cook time is about 5 1/2 hours or longer with a crock-pot. Of course, with dried beans it will take longer, and it is always a good idea to soak them prior to cooking.
Dehydration vs. Bad Bacteria
Some of the main degrading agents that cause your food to spoil over time are bacteria, mold, and fungi. Furthermore, certain food contaminants can be dangerous to health, causing food poisoning and other illness. When storing food, therefore, it is important to be knowledgeable of these contaminants in order to extend the shelf life of food, and protect your health. You will be happy to learn that proper food dehydration virtually eliminates the threats from deleterious contaminants. How? Mainly through the unique combination of these three factors!
Temperature: As expected, most bacteria that are pathogenic to humans thrive at human body temperature (98.6 °F). Once the temperature begins to rise above that temperature the growth of many bacteria begins to slow, and some even die; hence the effectiveness of having a fever when you are sick! Some common harmful food borne bacteria include Clostridium botulinum (botulism), Salmonella (salmonella food poisoning), and pathogenic Campylobacter or E. coli (food poisoning). The growth of nearly all strains of these harmful bacteria slows between 98.6 and 112 °F or higher. Dehydration is typically performed at 120-125°F for most items, except when dehydrating meat where higher temperatures are used (155-160°F).
Removal of Air: Some pathogenic bacteria are aerobic (thrive in the presence of oxygen), and some are obligate aerobes (will die without oxygen). As such, air removal via vacuum sealing kills or inhibits the growth of some pathogenic bacteria. Furthermore, a properly sealed vacuum bag will prevent new bacteria from landing on and colonizing your food.
Removal of Moisture: The most important deterrent to the growth of contaminants is the removal of water. If performed properly, dehydration should remove at least 95% of moisture, leaving 5% or less moisture content. Most bacteria, mold, and fungi cannot grow, and often die, below 10% water content. Food storage techniques such as freezing and canning, where the food is still subject to water, pose an increased risk for food illnesses if not performed properly.
As you can see, the common bacterial causes of food illness are not a significant cause for concern with food dehydration. The risk of bacterial contamination in properly dehydrated foods is extremely low, and is lower than canning and freezing, making it the safest food storage method of the three. In fact, the highest risk for contamination of your dehydrated foods is actually insects! To prevent this, simply make sure all of your food items are in sealed vacuum bags, Mylar bags, or buckets, and that your storage bags are not punctured.
Although the risk of foodborne illness resulting from dehydrated foods is extremely low, it is still important to practice proper hygiene and sterile technique. It is best to stay on the safe side and prevent any introduction of contamination when possible. Sterile technique is simple. Wash all items with soap and water, or rinse with water, before dehydrating. Make sure all kitchen surfaces and utensils are clean. Wearing latex or vinyl gloves will also help prevent the introduction of oils from your hands into your foods.
Dehydrators: Which one to choose?
When buying a dehydrator the most important thing to look for is the fan placement. The fan should be located on the back of the dehydrator NOT on the top or bottom. Dehydrators that are designed with a fan on top or bottom will dry your food unevenly thus creating confusing drying times and poor air circulation. Also if the fan is on the bottom flavors from foods on your bottom rack will travel into foods on higher racks, creating unwanted flavors.
I recommend Excalibur Dehydrators. I currently have two 9-tray Excalibur Dehydrators. One was purchased in 2007, and the other in 2009. Neither has given me a single problem and they both run constantly day and night and give fantastic looking products. These are by far the best dehydrators I have ever used. To ensure loyalty from my viewers I ONLY recommend products or services I have personally used and feel are the best available for the cost. For competitive pricing on Excalibur Dehydrators, and free shipping, click here!
For more dehydrator reviews, check out our review page!
Drying times
It is very difficult to give an exact time frame for dehydrating foods because of all the variables involved. Humidity outside and in the home, thickness and type of cut, how loaded the trays are, and even different brands of produce play a big part in dehydration time. Also, the type of dehydrator you use plays a large role. If the fan is on the top or bottom of your dehydrator it will take longer for the food to dry because the circulation of airflow is disrupted by the other trays. If the fan is in the back of the dehydrator (like these models) your food will dry faster and more evenly.
What I can tell you is this:
You never want to increase the temperature to dry food faster, as this will increase the risk of “case hardening.” This is when the outside of the food hardens and moisture is trapped on the inside. This will cause your food to spoil. Overall, the best drying method is “longer time, lower temp”. Never try to speed things up by increasing the temperature. Regardless if I am dehydrating a fruit or vegetable, I rarely go over 125°F.
Average* Drying Time List
8-15 hours All fresh vegetables including peppers
8-10 hours Frozen vegetables (remember to place on the tray while frozen)
8-10 hours Mushrooms and onions (sliced and chopped)
12-15 hours Sweet and white potatoes (thin sliced, chopped)
8-10 hours Fruits if sliced very thin
12-15 hours Fruits if cut in ¼ inch slices
15 hours plus Fruit rollups (depending on how much corn syrup and honey used)
15-20 hours Grapes
18-20 hours Blueberries
Up to 2 days Whole prunes (remove pits)
12-15 hours Peaches, plums, pears, apples, nectarines, rhubarb
* “Average” times are given since dehydration time can be altered slightly by an assortment of variables including humidity, type of dehydrator, and thickness of your food. The most important part is not so much the length of time in the dehydrator, but the percentage of remaining moisture left in your food. For long-term storage you want to stay at 95% and above. Testing for dryness will be your best barometer. Your food should easily snap and should not be sticking together.
Pro Tip: After dehydrating your food, place it in a zip lock bag for a few days before storing in your vacuum bags. This will give you a chance to see that your food has fully dehydrated. If your food appears limp you can put it back in the dehydrator again for a few more hours.
Foods that should be steamed before dehydrating
ALL LOW ACID FOODS:
Beets
Corn
Carrots
Asparagus
Cabbage
Peas
Beans
Broccoli
Potatoes
Cauliflower
Green Bean
Pumpkin
Peas
Foods requiring no prep
The following foods you simply slice and throw on your dehydrator; no pre-treatment of any kind is needed (i.e. no blanching, lemon juice, steaming, etc.)
Oranges
Lemons
Limes
Collard Greens
Spinach
Mushrooms (If wet or soaked in water before dehydrating mushrooms will turn dark in color. These are still OK to eat)
Parsley
Dill
All herbs
How to Dehydrate Frozen fruits and vegetables
Don’t forget that you can dehydrate all of your frozen fruits and vegetables from your grocery store, saving you room in your freezer. All your frozen foods have already been prepped, just open the bag and throw them on the tray frozen. This includes thick French fries and hash browns. Melons are better if pureed and made into fruit rollups. Frozen strawberries are easier to cut when they are only halfway frozen.
Fruit roll-up tips
- Never use sugar in fruit roll-ups, the sugar will crystallize over time. Instead use honey or corn syrup.
- When using zip lock bags to dry your fruit roll-ups, make sure any print on the bag is facing away from the roll-up.
- Use duct tape to tape down the zip lock bag so it does not fall off in the dehydrator and it is easy to remove from the trays.
- Shrink-wrap makes a great package for the roll-ups when sealed using your sealer.
- Also, the wax inserts in cereal boxes make a great package for fruit roll-ups.
- Cooking the fruit in a saucepan before dehydrating makes the roll-up translucent, whereas uncooked makes for a more firm and solid color roll-up.
Fruit Skins
Save the peels when peeling oranges, mangos, papayas, apples, peaches, pears, and lemons. Place the skins on the tray with the skin’s outer surface facing DOWN and dehydrate. After dehydrating, most skins can be ground and put in homemade herbal teas, sauces, cookies, cakes, and breads.
Fruit tips
In general, most fruits can be dehydrated at 120-125°F. The times for dehydrating fruits range depending on the fruit, and how thick you slice them. Also, different fruits sometimes require different prepping methods prior to dehydrating.
Basic Fruits:
Most fruits should be dehydrated 8-10 hours if sliced very thin, or 12-15 hours if sliced approximately 1/4 inch thick. Thicker slices will increase the time further.
Prior to dehydration most fruits require prepping. Often this entails simply slicing them to a uniform thickness, spreading them on the dehydrator tray, and spraying them with lemon juice. Citrus and other high-acid fruits are prepared the same way, except without spraying with lemon juice.
To download a list of some common fruits, their prepping instructions, drying time, and shelf life, click here!
Tricky Fruits:
Some fruits are trickier. Dehydrating prunes, for instance, takes up to 48 hours. Blueberries also require special attention and a few tricks. Click on one of the “tricky” fruits below to learn some secretes tricks to achieving the best final product!
Avocados
Bananas
Blueberries
Lemons
Papayas and Pineapple
Plums
Powdered Fruits
Raspberries
Herbal tea tips
Note: The following are claimed applications and effects of various herbs as explained via herbalism or herbal medicine. Herbs are considered supplements and not medications. As such, many of the effects and remedies listed below have been documented and observed by many people, but are (for the most part) not acknowledged by the FDA, meaning that you may or may not experience the same remedying effects of these supplements. Also, it means that there are no agreed or constrained “doses” for these supplements.
Keep in mind, it is always possible to have “too much of a good thing.” So, if you choose to embrace these wonderful potential benefits of herbs, please do so in moderation and with safety in mind. Don’t overdo it, and keep track of how your body reacts! Although you may find many of these herbal remedies effective in the treatment of various problems and symptoms, if you feel you have a serious or threatening illness you should consult a physician. You should not try to self-medicate via these supplements, or via other medications, without first contacting a medical professional. During yearly physician visits you should also list those supplements you use regularly under the “medications” section of your medical chart. Safety first!
Reported Benefits of Various Herbs, as Consumed in Herbal Teas
Chamomile May help ease emotional and physical tension and upset stomach.
Ginger May decreases the production of pain-causing chemicals in the body, and relieve respiratory congestion, nausea, and upset stomach.
Cat Nip May aid in relaxation and pain.
Passionflower May calm nervous tension.
Peppermint May have decongesting properties, and may aid with intestinal cramping and gas.
Echinacea (purple cone flower) is often used to suppress symptoms of common cold.
Lavender may help with insomnia, stress, and headaches.
Elderberry may be helpful for common cold symptoms.
Valerian may help with insomnia and mild pain reduction.
Mullein leaves are rich in mucilage, a gelatinous substance that may soothe irritated mucous membranes and bronchial passages.
Marshmallow Root also contains mucilage.
Thyme may soothe a nagging cough.
Yarrow may reduce inflammation and increase circulation.
Raspberry Leaf contains astringent compounds called tannins that may soothe intestinal inflammation.
Dandelion may stimulate digestion and help with water retention.
Licorice Root may increase the production of protective mucus in the stomach. Do not use if you have hypertension.
Parsley may have natural diuretic properties.
Herbs
Prior to dehydrating, never chop or cut any parts of the herb that you will be dehydrating (leaves, petals, etc.). This will release oils and reduce the flavor of your finished product. Instead, dry the plant as a whole and then break or crush after fully dehydrated.
Keep your dehydrator between 90-100°F. when dehydrating herbs.
If you wash your herbs first, dry any excess water (hang upside down to air dry or fold between a paper towel) before placing them in your dehydrator.
Honey
Although honey can be dehydrated, dehydrating honey is unnecessary because it will last indefinitely in its natural form if stored properly (unopened and at a reasonable temperature).
After opening, honey still has a very long shelf life, but it may crystallize. If your honey crystallizes into a gooey sugar after opening or storing it in a cold place, this does not mean that the honey has gone bad. Simply heat (but don’t boil) the honey and it will melt back its familiar and edible form.
How dehydrated should my food be?
You want to keep your food “95%” or more dehydrated because the more moisture you remove from your food the better chance of it lasting for many years. Now, there is no way to accurately measure the percentage of dehydration, but you can do physical tests to assess. First, after dehydrating let the food cool for 5-10 minutes before testing for dryness. For most items, if it is still sticky or feels moist, it is not 95% dried. Use your senses. A properly dehydrated item often feels dry to the touch, and some items can be torn like paper, while others will “click” when you drop them on the table.
If you aren’t sure, try to the zip bag test; put the items in a zip lock bag and come back a few hours later and look for signs of condensation/moisture.
How will you know? If it is sticky, put it back in the dehydrator!
Lemon Juice
It is important that you spray lemon juice on your carrots, apples, bananas, pears, strawberries, papaya, or any low-acid and non-leafy item before dehydrating in order to retain the natural beautiful colors of your fruits and vegetables. Additionally, this will add back vitamin C, as some of this is lost in any form of food preparation.
We recommend spraying lemon juice directly on the items instead of soaking them in a bowl. If you soak your bananas in the juice they will become soggy. Also, soaking food can take away important vitamins and minerals. If you put honey in the lemon juice, like some people suggest, I find that your food becomes sticky and soggy and after dehydrating it will stick together. Also, when soaking in lemon juice there is a lot of waste when you toss the leftover juice down the drain. Spraying or misting with concentrated lemon juice is the best technique.
Things you do not want to spray with your lemon juice are green leafy items like spinach or broccoli because the lemon juice will brown or burn them.
Pineapple juice is also a potential vitamin C-rich liquid that you can spray onto your foods before dehydrating. However, I recommend concentrated lemon juice because pineapple juice tends to make your finished product slightly stickier side due to the excess sugars.
A MUST: (All low-acid fruits, to maintain color and add extra vitamin C)
Apples
Apricots
Bananas
Pears
Strawberries
IF YOU WANT:
Raspberries
Rhubarb
NEVER:
Broccoli
Spinach
Longer time and lower temperature
You never want to increase the temperature of your dehydrator in hopes of a faster drying time. This will cause “Case Hardening.” This is when the outside of the food hardens and moisture remains trapped on the inside. This will cause your food to spoil. The best method to avoid this is using longer time and lower temperature. Regardless if I am dehydrating a fruit or a vegetable, I never go over 125°F. on my dehydrator. One exception is if it is very humid; then I might go to 130°F. with fruit, but no higher.
Make Bread Rise with a dehydrator
Yes, you can use your Excalibur Dehydrator to make your bread rise too! Simply turn the temperature to 115°F, remove all but one rack, and place a pan of water in the bottom of dehydrator. Then, oil your dough and cover it with a damp cloth. Next, put your bread on the rack above the pan of water and close the dehydrator. The rise time is about 1 hour.
Meats
I would not recommend dehydrating meat for long-term storage no matter how you package it. Dehydrated meat becomes rancid after a period of time. The only way to truly increase the life of the dehydrated meat would be to freeze it after dehydrating. That being said, dehydrated meat (i.e. jerky) is a delicious and fun snack for the family, and can be easily done with your dehydrator and stored for the short term in a mason jar with oxygen pack, or in the refrigerator in a plastic bag.
If you wish to have meat in your long-term storage, what I would recommend is to purchase freeze-dried meat from a company that sells it, or to can your own meat with a pressure cooker. I have stocked up on tuna, salmon, corned beef hash, beef stew and canned chicken. Tuna in a can has a particularly long shelf life.
Nutrients and Vitamins
In any type of food processing, from boiling and canning to simply cutting with a knife, some degree of nutrients are going to be lost. The unique technique of food dehydration, where gentle temperatures and long drying time tenderly remove moisture, is ideal for nutrient preservation in foods.
Compared to canning and freezing, dehydration is the superior food preservation method in regard to conservation of nutrients. The United States Department of Agriculture indicates that on average freezing foods for food storage yields 40-60% nutrient loss, while canning can create a whopping 60-80% loss. Home food dehydration, however, produces only 3-5% nutrient loss on average!
The secret is in the temperature. The extremely low temperatures used in freezing cause cells to lyse (break open), spilling out nutrients. On the other end of the spectrum, very high heats in canning can destroy nutrients and cells as well. Dehydration uses a long drying time in order to keep a temperature that is only gently elevated.
To key to optimal nutrient preservation is to remove key food-degrading agents: oxygen, light, and heat.
Oxidation is a reaction that alters the chemical structure of items, from sliced apples (browning) to sheets of iron metal (rusting). This reaction is often fueled by oxygen. The alteration of chemical structure by oxygen results in a loss of nutrients over time and will change the taste and appearance of the food. For long-term storage, therefore, it is optimal to vacuum seal items to remove oxygen, and add an oxygen pack to remove residual oxygen.
Light and heat both contribute to the spoilage of food and destruction of nutrients. Many vitamins, including vitamins A and C, are photosensitive, meaning they are destroyed by long-term exposure to light. For optimal long-term storage, therefore, it is best to store items in a cool and dark place, such as a basement, that is not damp. You may also double bag your vacuum bags inside Mylar bags, which have a tough and reflective outer coating to keep out light and heat.
Specific Nutrients in Dehydration:
Calories:
Dehydrating has no effect on calorie content. However, dehydrated foods have more calories per weight because removing the water shrinks the food and makes it lighter without removing any calories. The condensed product is consequently more calorie-dense. A calorie is a measure of the amount of energy in food.
Carbohydrates and other Sugars:
Dehydration has no effect on the total carbohydrate or sugar content in food. However, dehydrated fruit will be sweeter than non-dried fruit, since the removal of the water concentrates the sugar in the fruit into a smaller volume and weight. The removal of the water also makes the fruit lighter, meaning that a person eating the same amount in weight of dried fruit as a piece of fresh fruit would be consuming more calories and sugar. This can be good for hikers or athletes who may need a quick energy boost from a lightweight and portable food, but it can be problematic for dieters.
Fiber:
Dehydrating food has no effect on total fiber content. Fiber is a plant material that aids with digestion.
Minerals:
Minerals, such as iron, are not affected by food dehydration. However, some minerals may be lost during slicing of the food. In canning, foods are exposed to liquid long term, and therefore are more subject to mineral drain off.
Proteins:
Dehydrating food has no effect on total protein content. Protein consumption is important for proper development and growth.
Vitamin A:
Beta-carotene, which is converted to vitamin A in the body, is destroyed by contact with air. Beta-carotene is the substance in certain foods, such as carrots, that provides their brilliant orange color. You can witness the loss of vitamin A by simply leaving carrots out in the open. The vitamin A will begin to deplete, and the color of the carrots will fade. Luckily, this process can be prevented through blanching of items. The process of blanching before dehydrating some items will increases the quantity of beta-carotene, and change its structure slightly to prevent its loss. For an experiment, dehydrate some uncooked carrots and some blanched carrots and set them side-by-side. The blanched dehydrated carrots will not only appear much brighter orange, but over time their color will not fade. Vitamin A is important for vision, growth, and development.
Vitamin B:
B vitamins are water-soluble and are therefore sometimes lost in water drain off when slicing foods or blanching. Prolonged exposure to water, such as in canning, will increase the loss of vitamin B. Although vitamin B is water-soluble, it will not evaporate along with the water when you dehydrate, and so dehydration is a method of processing is gentle toward vitamin B loss. B vitamins are important for metabolism and many cellular functions in the body.
Vitamin C:
Vitamin C is a delicate nutrient that is easily lost in all forms of food processing and handling. The reason is that vitamin C is degraded by both air and light. The best way to prevent this vitamin loss is by removing the air, using vacuum sealing and oxygen absorbers, and removing the light by Mylar bag storage, or storage away from light. In addition, spraying some items prior to dehydrating will add a blast of vitamin C.
Vitamin C deficiency can causes a collagen disorder known as scurvy. Although we do not hear of scurvy much these days in a developed country, it still occurs. The best way to prevent scurvy is simply to eat a nourishing and well-rounded diet, with occasional consumption of fruits and vegetables. A healthy diet that consists of dehydrated and fresh foods poses no threat of scurvy.
Still, we recommend keeping vitamin C tablets in your food storage as well just in case. The high concentration of vitamin C in these tablets allows them to have a long shelf life if they are stored properly. Just as with your foods, you should remove the vitamin C tablets from the bottle and vacuum seal with an oxygen pack, and store away from light. As vitamin C naturally degrades, which is inevitable under any situation, its chemical structure changes making it inactive. Luckily, this altered form of vitamin C is not dangerous to consume, and therefore your vitamin C tabs will only lose potency over time, and not expire.
Dehydrating Onions and Garlic: Tips
Keep them separate! Strong-smelling foods should not be dehydrated in the same batch as other foods. Try putting your dehydrator outside on a hot dry day when doing your garlic and onions to avoid spreading strong unwanted scents through your home.
TIP: If onions make you cry, place them in the freezer for one hour before chopping them.
How to Dehydrate Plums
Remember, all prunes are plums but not all plums can be prunes. Plums need to be very ripe if you want prunes. To dehydrate, simply wash, leave the skins on and cut in half, remove the pit, then place skin side down on the dehydrator tray. Dehydrate at 120-125°F. until they are a little on the hard side. This should take 8-15 hours.
How to Dehydrate Potatoes
White Potatoes (‘Regular’)
If you boil potatoes with the skins on, then put them in the refrigerator overnight. This will firm up the potato and makes it easier to peel, cut, and shred. Make sure to cook your potatoes before dehydrating or they will turn black in the dehydrator. Do not overcook your potatoes or they will fall apart.
Mashed Potatoes
You will not be able to achieve mashed potatoes using dehydrated potatoes. It’s better to purchase potatoes that have been flake dried with special equipment (i.e. instant potatoes). I have found that getting the lumps out is a near impossible task when doing this yourself and it is much easier to simply buy from a company. The same goes for dehydrated eggs, milk, and cheese. These items require specific machinery and procedures; therefore it is far easier to find a reliable company to provide these products to you.
To purchase these commercially dried products click here!
Sweet Potatoes
If you want your sweet potatoes in slices or cubes then you will need to cut them first and then steam them. Always put them in water that is gently boiling. If you place them in water that has reached a rolling boil they will fall apart or mush. If you want mashed sweet potatoes, boil the potatoes with the skins on until cooked through, and then remove the peelings and gently mush them with your hands as you drop them on the dehydrator tray.
I never have had to place anything over the mesh tray when dehydrating mashed sweet potatoes; you can simply put your potatoes directly on the tray.
INSTRUCTIONAL VIDEOS
Powdered fruits and vegetables
Fruit powders can be used to make jellies and breads or can be added to sugar to give a fruity kick while cutting back on the amount of processed sugar being used. Powdered fruits can be put in oatmeal, yogurts, smoothies, shakes, desserts, sauces, teas, pies and drinks. The great thing when you dehydrate on your own is that the flavor is better and the nutrients are more abundant. This is because most of factories that make the powder you buy in stores use old fruit or left over peelings, and will often juice the fruits and simply powder the flavorless casings, and add sugar to hide this.
Rehydrating dehydrated foods
This is a good guideline to use, but also use your own judgment:
Vegetables: Approximately 1 cup boiling or cool (depending on the vegetable) water per 1 cup dehydrated vegetables.
Fruit: Approximately 1 cup boiling or cool (depending on the fruit) water per 1 cup fruit.
Allow the items to soak and absorb the water for 10 minutes or more (but no longer than 4 hours) before draining off the excess liquid. If rehydration is expected to take longer than 4 hours, use “Rehydration by Refrigeration.”
Rehydration by Refrigeration
This method, coined by us, is when you place your dehydrated items in a jar, fill with water, juice, or brine, and set in the refrigerator until rehydrated. Note that you are to use lukewarm liquid for fruits and boiling liquid for vegetables.
Rehydration by Refrigeration can be used to rehydrate fruit to make a delicious fruit salad and cucumbers into brilliant crunchy pickles that are better than anything store bought. You won’t believe your eyes, or your taste buds, when you witness the astonishing transformation take place. Green beans, corn, onions, peas, carrots, cabbage, and more will easily rehydrate using this method as well, creating vegetables that look and taste fabulous. Simply add hot water to your vegetables, set in the refrigerator, and come back the next day and heat and serve! It really is that easy.
How to: Add to a 24-ounce canning jar 1 ½ cups of sliced dehydrated items such as beets, apples, peaches, or zucchini. If using small chopped items such as peas, corn, chopped onions, etc. you would only require approximately 2/3 cups of the dehydrated items. For dehydrated vegetables, fill the jar to the top with boiling pickling, brine, or water. For dehydrated fruits, fill to the top with room temperature water, fruit juice, or spice water. After the water cools, place the jars into the refrigerator for 24 hours. The rehydrated items are a delicious snack right out of the jar. The hydrated vegetables can also be heated and served, and the hydrated fruits can easily be made into a fruit salad or pie filling.
Check out our comprehensive dehydration guide, The Ultimate Dehydrator Cookbook, for specific ‘Rehydration by Refrigeration’ recipes!
Shelf Life of Dehydrated Foods
When stored properly and kept in a cool, dry place your foods can last up to 30 years or longer depending on the item. To maximize shelf life it is important to dehydrate thoroughly, vacuum seal in a vacuum bag with oxygen packs, then “double bag” in a heat-sealed Mylar bag. These items should be kept in a cool place such as a basement.
Here is an approximate dehydrated food shelf life chart!
| Apples | 20 |
| Barley | 30 |
| Beans (Lentils, Kidney, Lima, Pinto, Refried) | 25 |
| Broccoli | 25 |
| Butter | 3-6 |
| Cabbage | 25 |
| Carrots | 25 |
| Celery | 25 |
| Cocoa Powder | 10 |
| Corn | 20 |
| Flax Seed/Powder | 10 |
| Fruit | 5-10 |
| Honey | Indefinite |
| Hulled Oats | 30 |
| Noodles | 10-15 |
| Onions | 25 |
| Peppers | 25 |
| Potatoes | 15 |
| Powdered Cheese | 3-6 |
| Powdered Eggs | 5-10 |
| Powdered Milk | 25 |
| Rolled Oats | 30 |
| Salt | Indefinite |
| Soybeans | 10-15 |
| Sugar | Indefinite |
| Sprouting Seeds | 15+ |
| Unbleached Flour | 10-15 |
| White Flour | 10 |
| White Rice | 30 |
| Yeast | 3-5 |
Steamer/juicer marble trick
Place 6 or 7 marbles in the bottom of your Steamer/Juicer (where the water goes). The marbles will rattle against the side of the pot when your water is getting low, acting as an indicator that you need to add more water.
Stop small foods from falling between the trays
Pulling a pair of queen size pantyhose over the tray is a great way to prevent the small items from falling between the trays. You can wash the nylon and reuse it. Going to a fabric store also offers a lot of different ideas for a screen cover that can be washed.
Tomato paste and tomato sauce roll-ups
There are several options when making tomato paste:
- Puree tomatoes that have been canned
- Use whole tomatoes, scald off the skin, then puree
- Puree whole tomatoes with the skins on
- Pre-cook your puree as you would with fruit roll-ups, or simply dehydrate it raw
A trick you can use to help remove water from the tomatoes is to put them in a clear gravy separator and place them in the refrigerator overnight. The next day, pour off the water that separated from the tomatoes. Your paste will now be thicker and easier to make into a roll-up.
Vegetables
When dehydrating, vegetables largely fall into three main groups: those you simply slice then dehydrate, those you blanch/steam prior to dehydrating, and those that require special tricks. For all of these groups you can simply dehydrate at 120-125°F. for 8-15 hours after preparation (depending on thickness of slice, type of vegetable, and humidity in your home).
To download a chart of drying times for specific vegetables, click here!
Group One: These vegetables are simply sliced thinly then dehydrated
All Bagged Grocery-store Frozen Vegetables (no slicing required)
Collard Greens
Mushrooms
Onions
Spinach
Group Two: These vegetables must be steamed prior to dehydrating
Asparagus
Beets
Broccoli
Cabbage
Carrots
Corn
Cauliflower
Peas
Pumpkin
Summer Squash
Zucchini
Group Three: These vegetables require special preparation techniques, precautions, or extra attention. Click each for more information.
Potatoes
Tomato Paste/Sauce
What CAN’T be dehydrated?
You can dehydrate so much; from fruits and vegetables to sauces and cake fondant and much more. The limit lies virtually in the boundaries of your creativity! There are, however, a few items that simply will not dehydrate properly and efficiently:
High Oil Content: Items with naturally high oil content will not dehydrate properly. Examples include avocados, Nutella, and nuts. Some items, such as olives and meats, have “medium” oil content. These items can be dehydrated, however, they will not last as long as your fruits and vegetables, spoiling fairly quickly. I would not recommend storing olives or meats for longer than 2-3 months (6 months if freezing in addition to dehydrating).
Lettuce: Lettuce does not yield a favorable product when dehydrated. The resulting product appears wilted and burnt, and you cannot do much with it. Luckily, the health benefits of lettuce are limited (fiber and some vitamin A), and thus it is not an essential part of your storage. You can supplement vitamin A and fiber into your storage through a number of other fruits and vegetables. There are plenty of other leafy greens, such as collards, that dehydrate nicely.
Some Animal Products: Animal products such as milk, eggs, and cheese are not easily dehydrated through conventional home methods. These products contain higher oil content and thus require special commercial methods of dehydration for a high-quality and long-lasting product. There are some exceptions in which you can dehydrate these at home. To learn more click here to see our Helpful Tip on this topic. To purchase these commercially dehydrated items, click here.
Wheat: milled or not?
Wheat will store for up to 30 years if left un-milled in the berry form. Milled flour will last for 5 years if you store it with oxygen packs in a vacuum bag that is double bagged in a Mylar bag, and then placed in a bucket with an air tight rubber seal. You should find the coolest spot in your home to store your food.
When to salt
Remember to add salt only AFTER everything is cooked. Salt slows down the rehydrating process.
Why dehydrate?
When people think you’re crazy for storing food, just forgive them and keep on storing. Building a pantry for your family is one of the smartest things you can do. It’s not about digging a hole and hiding it, it’s about preparedness against hyperinflation so that we will always be able to afford food for our families. It’s about having a reliable source (and a green source) of storage that does not rely on electricity or refrigeration.
A few years ago we had a storm in our city and lost power for two weeks. As a result, nearly all of the food in our refrigerator and freezer had to be thrown out. It is important to learn to preserve and cook with our dehydrated and stored food so that we can bring the greatest amount of security to our loved ones in the event of disaster, or even something as sudden as a loss of electricity.
Too, it doesn‘t make sense to waste money on overpriced prepackaged foods from the store when you can do it yourself for a small fraction of the price! With dehydration you can prepackage your own meals with food from your garden or food you have selected yourself from the store. For instance, if you have bananas that are not being eaten fast enough, you don’t have to throw them out, you can dehydrate them!
Compared to other storing methods, dehydrating takes a fraction of the space, weighs less, saves money, requires no refrigeration, and will last up to 30 years or longer. Dehydration is also gentler on your foods than canning or freezing, meaning that less nutrients and vitamins will be lost (losing some nutrients is inevitable when processing or cooking foods in any way). In fact, studies by the United States Department of Agriculture show that only about 3-5% of nutrients are lost during dehydration, whereas around 40-60% can be lost during freezing, and around 60-80% during canning.
Dehydrating makes cooking easier, it is an easy way to be greener and waste less, to save money, to live healthy and clean, to secure your family, and it’s fun!
Yogurt
When making yogurt, make sure your jars and lids have been sterilized and dried thoroughly. You don’t want to breed any bacteria other then the bacteria that makes the yogurt.
INSTRUCTIONAL VIDEO Yogurt
RECIPE AVAILABLE Yogurt
Note: Do not add the heaping tablespoon of commercial plain yogurt until the temperature of the milk is at or below 120°F. but not lower than 100°F. Remember, a temperature over 120°F. will kill the culture and you will not be able to make yogurt. If the temperature drops below 100°F. the milk will sour. To be safe, keep your dehydrator between 118-120°F.
