Dehydration vs. bacteria
Enemies in long-term food storage
Holes in your vacuum bags
How to get FREE food storage buckets
Nutrients and vitamins
Oxygen packs (absorbers)
Prepackaging dehydrated soups
Reusing your can lids
Shelf life of dehydrated foods
Vacuum sealer and bags
Where to store your food
Basic tips before you start
Food storage knowledge is important to make sure your food stays good to eat for the longest time!
Click here for a PDF document with some important beginner tips and information for dehydration and food 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 are natural oils and moistures in your hands, which will contaminate your foods by reintroducing moisture.
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 foodTry 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.
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 food 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.
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 foodborne 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.
Vacuum Bags: Vacuum bags can be suction sealed with a vacuum sealer. Place your dehydrated foods, quick meals, bread mixes, etc., into a vacuum bag, add an oxygen pack to remove residual oxygen, and vacuum seal.
The purpose of vacuum sealing is to remove oxygen from your food. Oxygen is a powerful food-degrading agent. In addition, removing oxygen creates an environment that is difficult for many species of bacteria to grow, adding to the safety of your stored food.
Mylar Bags: Mylar bags cannot be vacuum-sealed by most non-commercial vacuum sealers, so instead you must heat-seal them. Some vacuum sealers, such as the Weston Pro-2300, have a “heat seal” button. This allows you to simply fuse the bag shut with heat and without suction. If your vacuum sealer does not have this feature, you can heat seal using an iron and a metal edge.
Mylar bags are made of a durable and resistant reflective material. Thus, the purpose of the Mylar bag is to keep out sunlight, and reduce heat. Light and heat are also powerful food-degrading agents. Additionally, Mylar bags help to prevent puncturing of your bags by sharp objects or rodents.
Need any of these items? Click Below:
Enemies in long-term food storage
- Rodents and Bugs
Locating a farmer’s market in your area and buying by the bushel is a great way to save money and build your pantry. When potatoes are in season I purchase and dehydrate enough to last through the winter. During the fall when it’s apple season I can purchase a bushel basket of apples for $5.00. Normally I buy around 5-6 bushels, which will last me through the winter. I dehydrate the apples, vacuum seal them in vacuum bags, and heat-seal the vacuum bag inside of a Mylar bag (“double bagging”), so that they will last up to 30 years. Then, I use the dehydrated apples periodically to make apple bread, muffins, pancakes, pies, and many more delicious recipes! All winter I never have to peel or cut anything, and I can make meals fast and easy.
Glass jars can be used for short-term food storage. When they become empty, simply refill them with items from your long-term food storage (i.e. items that have been vacuum packed, and or Mylar bagged). Your food will last for a year and longer in the jars, but long-term storage will push this shelf life longer. An issue with storing in jars is light exposure, which slowly breaks down food. Therefore, try to store your jars away from direct sunlight exposure. Years ago, jar companies made a blue jar for canning to deter light. You can still find the blue jars if you go to attic or garage sales for a discounted price. I would not recommend these old jars for liquid canning due to safety reasons, but they are great for long-term storage of dried foods. Some stores also carry the blue jars.
Holes in your vacuum bags
The likely reason for puncturing of your vacuum bags is the quality of the bag itself. I always say: If you are to spend a little extra money anywhere when dehydrating, buying vacuum bags is the place to do it! You can have the best vacuum sealer on the market, but if your bags are low quality they will puncture and your food and hard work will be wasted!
Most often when I receive this question, the inquirer is using FoodSaver brand vacuum bags. I would consider FoodSaver bags lower quality. FoodSaver products are nice because they provide a low-cost option for those just starting to dehydrate and store. However, I would avoid using their bags if possible, especially if you are storing a large amount of goods. Try to purchase vacuum bags and Mylar bags of 3Mil thickness or greater, and from a company you trust! You may need to shop around to find what you like best.
Tammy of Dehydrate2Store uses the following:
Tip: If you must use lower quality bags, try wrapping them in bubble wrap. This will reduce impact when heavy items are placed on top and will reduce puncturing.
How To Get FREE Food Storage Buckets
If you want to get food storage buckets for free simply drive behind a doughnut store, restaurant, or bakery. I have found 10 at a time sitting outside the dumpster while driving by a bakery in my neighborhood. These can be sanitized and used, as they are already food grade. Alternatively, you can go inside the store or restaurant and ask them to save the empty buckets for you. Most places will do this. You will be surprised how many buckets you can accumulate over a short period of time. If the seal of the lid is in bad condition then purchase a new lid with a good rubber seal at any home supply store. I like “Tractor Supply” store as those lids have a quality seal and are affordable.
Make sure your storage buckets are “food grade.” Food grade plastic is held to a higher standard of purity to ensure chemicals and plastics do not seep into your food. If the bucket previously held food, it is an indicator that the bucket is food grade. If you purchase new buckets you should also make sure they are food grade. The manufacturer should be able to tell you that information.
If it is a warm rainy day and the windows are open and you don’t have air conditioning or a dehumidifier running, then hold off until another day before dehydrating. When the conditions are as I just mentioned, you are asking your dehydrator to dehydrate your food and your whole house! Attempting to defeat this will only cause you to be upset with the dehydrator thinking you have a bad one. Just relax, sit back, and be thankful for all the wonderful rain that will bless you with an abundance of food to dehydrate later on.
The Church of Jesus Christ of Latter Day Saints (LDS) has canneries that you can go to and purchase Mylar bags and oxygen packs for a great cost. You can also purchase wheat, oats, corn meal, beans and other dried foods and have it placed in #10 cans for you. The LDS members are very kind, willing to help, and very knowledgeable in food storage.
You do not have to be a member to go to some of the canneries; however the canneries are non-profit and therefore run through tithing in the church. For this reason some locations require that you be a member to purchase from them. Call your local cannery and ask their policy before visiting. Through the usage of an LDS cannery you can build your pantry fast and for very little money. The Cannery is a smart tool in helping you build your pantry, so please take advantage of it.
If you are interested, click here to find a map of all of the LDS canneries in the United States. Click on the state in which you live, or a surrounding state, to find the nearest one!
Mylar bags are reflective silver bags that are durable and puncture resistant, making them a perfect second line of defense for your vacuum-sealed bags. Also, the shiny coating reflects sunlight, a powerful food-degrading agent.
Mylar bags are very important for long-term food storage (up to 30 years). The bags keep out harmful sunlight, protect against puncturing, and keep out rodents. You should store your Mylar bags in a cool place, such as a basement storage area.
To Seal a Mylar Bag
Mylar bags cannot be vacuum sealed directly. The Mylar material is very strong: too strong for virtually any non-commercial food-sealing machine. Even the Weston Pro-2300, the highest quality sealer I have ever used, cannot seal these bags directly. Trying to do so may harm your machine.
Part of the reason is the strength of the bag, and part of the reason is the material. Mylar bags are not designed to be sealed. They do not have microchannel pockets for efficient air suction, and the bag’s surface does not provide a proper grip for use with a vacuum sealer.
To seal a Mylar bag, simply put your vacuum-sealed vacuum bag inside of a Mylar bag and then use the “heat seal” setting on your vacuum sealer. If you do not have a heat seal setting, you can use a hot iron and a metal surface.
Alternatively, you can use this trick. Put your food into a Mylar bag, but don’t seal it. Then, put the Mylar bag into a larger vacuum bag. Make sure the vacuum bag is 1-2 inches longer than your Mylar bag. Next, use your vacuum sealer to vacuum seal the vacuum bag. The suction created by the vacuum bag will cause the Mylar bag to vacuum seal as well.
Note: Just like vacuum bags, the quality varies depending on company. Using high-quality bags is important to ensure your food lasts the maximum time. For the high-quality 3Mil durable Mylar bags I use in my videos click here.
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 food 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 food 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:
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.
Dehydrating food has no effect on total fiber content. Fiber is a plant material that aids with digestion.
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.
Dehydrating food has no effect on total protein content. Protein consumption is important for proper development and growth.
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.
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 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.
Oxygen packs (absorbers)
Oxygen packs (or “Oxygen Absorbers”) are small oxygen-absorbing packages that are to be placed into your vacuum-sealed bags, buckets, or jars of dehydrated foods. The purpose of an oxygen pack is to absorb any residual oxygen that may still be present in your bag, bucket, or jar.
What size to use?
100cc per one-gallon vacuum bag or glass jar.
2000cc per five-gallon bucket containing a five-gallon Mylar bag. This is something you would use when you are placing items directly into the Mylar bag and not vacuum-sealing them. Examples: Wheat, oats, corn, beans, barley, and so on.
How to store oxygen packs?
Your oxygen packs will likely come in a vacuum bag when you purchase them. Cut a thin strip off of the bag, remove the packs you need, and promptly reseal the bag with your vacuum sealer. If your oxygen packs do not come in a vacuum bag when you purchase them, put them into a vacuum bag after you first open them.
Often, oxygen absorbers come with a pink pill inside of the vacuum bag. This pill serves as an indicator of oxygen exposure. If the pill turns blue or purple it means that oxygen has gotten into your oxygen pack storage, and your oxygen packs are likely no longer good to use.
When must you replace them?
When you open a mason jar and no longer hear the “POP” suction sound then it is time for a new oxygen pack. If you open a jar and hear a pop, then close it and open it again fifteen minutes later you will not hear the suction noise again. This does not mean you need a new oxygen pack because a jar usually takes a few hours for the lid to be suctioned closed.
If there are foods that you are opening and closing on a daily basis then there is no need for an oxygen pack because the food is being rotated quickly.
To purchase high-quality oxygen packs of various sizes click here
Prepackaging dehydrated soups
If you are making prepackaged soups for easy cooking, or to give away to friends and family as gifts, simply add all spices and ingredients directly to the mix and then vacuum seal. The only things you must keep separate are the bouillon cubes (because they contain moisture), cornstarch, and flour (because it will absorb moisture). Place each of these items in their own little separate sealed bags or zip lock bags. Place all of the little bags right into the large vacuum bag containing the rest of your dehydrated ingredients.
Reusing your can lids
When a jar’s lid has been pressure-canned and then opened, the seal on the lid is compromised and could potentially leak air. However, you can reuse lids from jars that were used to hold dehydrated foods because the lids were not processed in a pressure cooker.
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.
Click here for more information and a dehydrated food shelf life chart.
Vacuum Sealer and Bags
What to buy: Vacuum Sealer
One of the best investments you can make in food storage is purchasing a vacuum sealer. Not only is a vacuum sealer necessary for the long-term storage of many foods, but it can also be used for so much more. Examples: Medications, soaps, blankets, important papers, making small car emergency packs, matches, clothes, and anything else you want to protect against moisture. You can also vacuum seal your store-bought cheese to make it last four times as long. The same goes for all of the other leftovers in your refrigerator. In addition, vacuum sealing helps to save space by compressing bulky and soft items such as blankets.
I recommend the Weston Pro-2300 Vacuum sealer. This high-quality and durable machine is great for abundant vacuum sealing. This machine comes with dual suction motors, instead of many other brands that have only one, which allows for powerful suction strength. This also has the option to heat seal without vacuum sealing, which is great for Mylar bags.
For long-term food storage, it is important to have good quality bags and a good quality sealer to create a strong long-lasting seal and ensure the food you worked hard for stays safe!
To see this sealer in action click here!
To purchase the Weston Pro-2300 Vacuum Sealer click here!
What to buy: Vacuum Bags
Regardless of which vacuum sealer you have, the most important thing is the bags! You must have vacuum bags of at least 3 Mil in thickness, and they must be of durable quality. If there is one time during the storing process where you shouldn’t settle for the cheaper product, it is right here. You can have the most expensive vacuum sealer on the market, but if you are using poor-quality bags your food storage efforts will be futile.
I prefer the microchannel 3-Mil bags that can be found here for their durability and longevity.
I am not a big fan of the cheaper bags that can be found at department stores like Wal-Mart. Your food storage is important, and it does not pay to use cheap vacuum bags.
If you must use lower quality bags for budget reasons: Put your dehydrated food in a plastic zip lock bag, but do not zip it closed. Then place that bag into your vacuum bag and vacuum seal. This will provide added thickness. But remember, I always recommend higher quality 3 Mil or higher bags if possible.
Where to Store Your Food
You should never store your food on a concrete floor. Place it on a skid or elevate it off the floor so it is not directly on the concrete. Never place your stored food where the sun is beating down on it, by a furnace, or anywhere that is especially hot. You do not need to refrigerate dehydrated food, but it should be stored in a cool and dry place away from sunlight.