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Shelf Life of Freeze Dried and Dehydrated Food

There are many factors that can affect the storable life of your freeze dried and dehydrated bulk food. Please take the time to read this information page if you are not aware of how foods are packed and how they should be stored.

Dehydration and freeze dried techniques have come a long way in recent years. Old technology left as much as 30% moisture in the dehydrated products. These poorly dehydrated foods didn't store very well. Recent advancements in technology have made significant improvements, with moisture levels now at 2% or 3%. Gone are the pliable dehydrated foods. Now they break with a crisp "snap" when bent. With moisture levels reduced to 2% - 3%, storage life has been increased dramatically.

Storage Temperature

It is important to keep in mind that not only do colder temperatures affect shelf life of food products, temperature fluctuations affect shelf life too. Keeping your food stored at a constant temperature will help you achieve the maximum shelf life. As you can see from the below chart, it is not that hard to obtain 10+ years on your food storage. Finding a cool, dry location, such as a basement or root cellar is perhaps your best insurance on maximizing the shelf life on your stored foods.

Storage Life & Temperature  

Temperature and temperature changes have the most to do with the shelf life of stored food than any other factor. The USDA states: "Each 5.6 C. (10.08 F) drop in temperature doubles the storage life of the seeds." Experience has shown that this applies to foods too.

TemperatureYears
37.6° F
40
48.4° F
30
59.2° F
20
70.0° F
10
80.8° F
5
91.6° F
2.5
102.4° F
1.25

(See also the product chart below )

Foods that will be prepared and consumed rapidly don't need any special storage requirements. Such foods can be stored at room temperatures with no appreciatable loss of quality or nutrition. The above chart demonstrates that bulk food can be stored in warm areas for several years.

We are often asked about food storage in a garage, shed or outside. This is certainly possible, it's just not the best choice. Higher temperatures will shorten shelf life, lowering the nutritional quality, but the food remains edible even in a lower nutritional condition in most cases. Cans should be protected from moisture and humidity, while buckets and pouches will be unaffected. Higher temperatures simply means a shorter shelf life, but this is still far, far longer then "supermarket food" and their packaging, which is just a few months to 2 or 3 years for canned food.


A Few Comments About Canned Foodcanned food items

Don't believe the Hollywood versions of 'survivors' of the "Apocalypse" eating store-bought food (cans or packaged food, also known as wet-pack food) scrounged from abandoned stores or hoarded away decades later. This narrative is completely false and while it might make for an entertaining movie, it would also kill the remaining population that dared eat it.

Supermarket food of all types will have long spoiled, or rotted away, even inside the cans due to bacteria or acidity. Even the cans themselves are not intended for long-term storage. Packaged store-bought food in boxes or plastic containers or wrapping will be utterly ruined and unfit to eat. Oxygen, mold and bacteria will have long ago ruined any possibility of eating such food. Eating any of these foods will probably kill you. Starvation will then finish the job.

The reality is any survival shelters stocked with supermarket food must be constantly rotated and replenished (monthly) to ensure nothing is ruined or spoiled. But it is a very short-term "preparedness plan" in reality, which is why we have never recommended this. Canned wet-pack food will last a few years at best (2 - 5 years, please review Still Tasty for the actual facts on wet-pack food shelf life), but beyond that it would be extremely risky to dare eat it.

The facts are there is no such thing as canned wet-pack food lasting decades. We see a lot of people making this mistake, stockpiling canned food for hard times years or even decades ahead. They are wasting their money (unless they can eat it fast enough). The only way you can acheive this type of food security is by storing foods specifically processed for long shelf life and stored in airtight containers in a cool location. Only dry food, dehydrated or freeze dried food offers this longevity.

Airtight containers (with oxygen absorbers) will prevent oxygen, bacteria, mold and mildew from reaching the food. See our Food Storage Basics article. Containers must be oxygen-impermeable (no oxygen transmission through osmosis), which is why we always recommend Mylar bag liners in our buckets of food, or the mylar food pouches we carry or hard-sided cans, and everything with an oxygen absorber sealed inside.

Real food security means doing the job right, the first time and not wasting time, effort and money on something that doesn't work. Hollywood versions of 'reality' are often serious misrepresentations of just what it means to deal with critical food shortages.


Moisture Content

Many products, such as dry beans, grains, and flours contain an average amount of 10% moisture. Although it is not necessary (and very difficult) to remove all moisture from these kinds of dry foods, it is important that any food stored be stored as dry as possible. Excess moisture can ruin your food stored. Our suppliers package up these products using only dry, high-quality food and seal them in airtight containers (cans or buckets) with oxygen absorbers. We do sell bagged (loose-packed) beans, flour and grains, which if intended for long-term storage, need to be repackaged into airtight containers (we also recommend using oxygen absorbers and if in buckets, mylar bags).


Oxygen Content

Oxygen can be removed from the food storage container, resulting in the food lasting much longer than normal. Oxygen, naturally found in air will oxidize many food compounds. There are a couple of techniques used to remove oxygen from food containers:

  • Displacing the oxygen with nitrogen: Air is purged out by inserting a nitrogen wand into the food container. Nitrogen is the most inert gas known.
  • Absorb the oxygen: The oxygen absorber packet absorbs the oxygen. Air contains about 78% nitrogen and 21% oxygen, leaving about 1% for the other gasses. The oxygen is absorbed, leaving about 99% pure nitrogen in a partial vacuum. Our food products in cans or buckets all come with oxygen absorbers in their containers.
  • Dry Ice: Home storage can be accomplished by using dry ice (carbon dioxide) obtained from a local source. The dry ice is place in the container (usually a bucket) and allowed to evaporate, displacing the oxygen. It's no longer commonly used when oxygen absorbers are so readily available and cheaper, but it will work.

Storage Containers

An air tight seal on the food storage container is a must. All of our food is packed in air tight, sealable food grade cans or buckets with gasket lids (except for items ordered in bags or boxes) with an appropriately sized oxygen absorber.

Some foods are available in Mylar pouches which are airtight if left unopened. Maximum shelf life is achieved best with either cans or buckets. Boxed or bagged items can be consumed immediately or repackaged into food grade airtight containers. We recommend buckets with gasket lids and / or heavy Mylar bags with oxygen absorbers for boxed or bagged products.


Storage Location

To ensure maximum shelf life, store your food storage in a cool, dark location out of direct sunlight. Avoid direct contact with concrete floors by elevating your cans or buckets off the floor with pallets or wood boards. High humidity evironments will affect opened containers, but will have no affect on factory sealed air-tight containers.

Barometric pressure can dent or - in the case of severe barometric pressure changes (altitude, hurricanes, etc.) - severely dent buckets. This is usually a "good sign", since it indicates a tight seal on the gasket lid. Generally bucket dents only occur with people who live at very low elevations near sea level. The lower in elevation you are, the more atmospheric pressure there is, consequently the buckets can dent. If these are SP buckets (the food is in a sealed mylar bag inside) and you want to remove the dents, you can crack the lid open and allow in some air, but this is not always necessary or generally recommended.

Dents can be ignored unless they are problematic and threaten the integrity of the bucket. In the case of severe dents the lids can be removed on SP buckets (products with mylar bags) and the sides pushed out and the lid replaced. Do not do this on RB (ribbed) buckets as they do not have a mylar bag inside (unless you replace the oxygen absorber after pushing out the dent). We always recommend the SP buckets over the RB buckets since the mylar bag provides an extra layer of protection. Customers are responsible for making periodic inspections of their food storage and ensuring proper storage conditions.


Average Shelf Life of Dehydrated Products - Rainy Day Food Line

Below is a chart to help you determine the shelf life of food stored in air tight containers at an optimum temperature of 60 degrees (cooler, colder temperatures are best). All of the following products will store proportionally longer at cooler temperatures if kept at lower storage temperatures. Higher storage temperatures will decrease shelf life. Shelf life of 30+ years is perfectly feasible for many products with proper storage conditions and temperatures!

Shelf life beyond these figures decrease in nutritional quality and taste. All foods should be checked prior to consumption for staleness, bad odor, or obvious signs of deterioration. The above table represents average shelf life for these products and is not a guarantee.

Average Dehydrated Product Shelf Life

ProductYears
Apples20+
Adzuki Beans25+
Alfalfa Seeds15+
All Purpose Flour10 - 15
Bakers Flour15 - 20
Barley30
Black Turtle Beans25
Blackeye Beans25
Broccoli25
Brown Rice3 - 5
Buckwheat20+
Butter &
Margarine Powder
3 - 5
Cabbage25
Carrots25
Celery25
Cheese Powder10 - 15
Cocoa Powder10 - 15
Corn20
Cornmeal20 - 25
Cracked wheat20
Flax10 - 12
Fruit20+
Garbanzo Beans25
Garden Seeds3 - 5
Germade30
Gluten5 - 10
Granola1
Great Northern Beans25
Groats30
Hard Red Wheat30
Hard White Wheat30
Honey, Salt, & Sugar
Hulled Oats30
Kamut30
Kidney Beans25
Lentils25
Lima Beans25
Macaroni20+
Millet25+
Mixes *3 - 10
Noodles10 - 15
Onions25
Peppers25
Pink Beans25
Pinto Beans25
Popcorn30
Potatoes (all)20
Powdered
& Whole Eggs
5 - 10
Powdered Milk25
Quinoa20
Refried Beans25
Rolled Oats30
Rye30
Small Red Beans25
Soft wheat30
Soybeans10 - 15
Spaghetti20+
Spelt30
Sprouting Seeds15+
Triticale30
TVP10 - 15
Unbleached Flour10 - 15
White Flour10
White Rice30
Whole Wheat Flour10 - 15
Yeast *3 - 5
∞ = Indefinitely.

 Shelf life estimates are based on industry studies from sources deemed reputable. Since individual storage practices and conditions will vary, Food Assets and the canneries must disclaim any liability or warranty for particular results.

* Products that contain yeast (leaven) should be considered as having a shorter shelf life than products that do not contain this ingredient. There are active enzymes in leaven, which create carbon dioxide gas, the same gas used in food storage (dry ice method). The gas is harmless to food. Leaven by itself has a 2 year shelf life (see Yeast above).


Average Shelf Life of Freeze Dried Products

Freeze drying is the most effective way to remove water from food. Freeze-drying (also known as lyophilization or cryodesiccation) is a dehydration process typically used to preserve food and make it more convenient for transport and storage.

Freeze-drying works by freezing the food and then reducing the surrounding pressure in a vaccuum and adding just enough heat to allow the frozen water in the food to sublime directly from the solid phase to the gas phase.

If freeze-dried food is then sealed (in osmosis proof containers or mylar pouches) to prevent the reabsorption of moisture, the food may be stored at room temperature without refrigeration, and be protected against spoilage for many years. Preservation is possible because the greatly reduced water content inhibits the action of microorganisms and enzymes that would normally spoil or degrade the food.

Freeze-drying also causes less damage to the food than other dehydration methods that employ the use of higher temperatures. Freeze-drying does not usually cause shrinkage or toughening of the material being dried. In addition, flavors, smells and nutritional value generally remain unchanged, making the process popular for preserving food. For optimal shelf life it is best to store the products in a cool, dry environment. We recommend 65º or less; the cooler the better. High heat that occurs in a garage or the trunk of a car is not good for freeze dried products.

Key advantages of freeze-dried products:

  • 98% of the moisture is removed.
  • Retains the original taste and nutritional value of the food.
  • Foods are quick to reconstitute and easy to prepare.
  • Hot or cold water may be used for reconstitution (although cold water takes longer).
  • Extends the shelf life of the product.
  • No preservatives are necessary.
  • Results in a super-lightweight / compact product.
ProductYears
Mountain House Cans (1)30+
Mountain House Pouches (2)30+
Van Drunen Farms Cans20+
Mainstay Food Rations (4)5+


1. Mountain House freeze-dried foods are packed in airtight NITROGEN PACKED #10 cans. Up to 98% of the residual oxygen has been removed. Their unique canning process uses both vacuum oxygen removal and nitrogen flushing. This is a time consuming and slightly more costly process. It is the same process mandated by the U.S. Military for whom Mountain House produces freeze dried food for.

Effective 7/26/16:  This also applies retroactively to products purchased before this date.

Must Read: Important Mountain House press release regarding Wise Foods (revealing information), and also, Mountain House products exceed 30 year shelf life.

January 3, 2013 Notice:

"We recently tested archived samples for nutrition, flavor, and texture, and found them to be virtually indistinguishable from new production, the very definition of “shelf life”. As a result of our testing: Effective immediately, the official shelf life of Mountain House pouches has been increased by over 40%, from 7 years to 10 years!

"We also tested Mountain House pouches that were 30 years old. While there were recognizable differences in flavor and texture from new production (and therefore past their “shelf life”), the food was still delicious, wholesome, and nutritious! In fact, our tasting panel found that 30-year old Mountain House food significantly outscored newly manufactured competitive products in a blind sensory evaluation.

"We are confident that Mountain House provides consumers with the longest proven shelf life in the industry, as well as the longest proven storage time: our food remains not just barely edible, but delicious!"

2. Mainstay Food Rations are not freeze dried products - they are specially formulated rations designed to survive temperature extremes that would destroy typical foods. These can be stored in a boat, car, camper, etc., where there are temperature fluxuations that would ruin MRE's.

Some important links relative to 3rd party lab testing, packaging properties, and their results

Moisture Penetration at End of Stated Shelf Life

Barrier Testing of Pouch Products


Columbia Laboratories Testing of Wise Food pouches


Average Shelf Life of Real Meat Products

We offer a selection of 100% real meat products packed in cans. These are slow pressure cooked in their own juices and hermetically sealed in cans. Currently Rainy Day offer the best in long term storable meats. Shelf life is based on storage conditions of 65º F. You can extend shelf life even further with cooler storage temperatures.

Rainy Day Signature Meats shelf life: 3 - 5+ years.


Shelf life of MRE's

MRE's remain in high demand - and for their intended usage, they can definitely serve a purpose in your food storage program. We recommend these for shorter durations or wherever you need ready to eat meals without any preperation (cooking). These can be passed out as needed for emergency disasters and eaten immediately. Keep them stored in a cool location to maximize their shelf life. Temperature plays the biggest role in the duration of shelf life and will greatly affect the taste and quality of MRE's as well.

We carry the XMRE line of MRE's.

MRE Shelf Life Chart


More on Shelf Life

Predicting actual shelf life of dehydrated foods is not an exact science, however there have been many studies done. In addition to the above average shelf life of food stored at a constant 70 degrees, you can dramatically increase your life expectancy by lowering the constant temperature. It is possible to double, triple or even quadruple the shelf life by lowering the temperature proportionally.

Some products, such as seeds, can even be frozen for dramatically increased shelf life. The basic rule of thumb is to store your food storage in as low of temperature as possible to increase its shelf life and to retain nutritional value.

A new study by the Department of Nutrition, Dietetics and Food Science at Brigham Young University tested several varieties of dehydrated stored foods in #10 cans. They have learned that shelf life is considerably longer than previously thought. Here are their findings:

Nutritional Adequacy and Shelf Life of Food Storage by Dean Eliason and Michelle Lloyd

Is my food storage still edible? How is the nutritional value?

In the Department of Nutrition, Dietetics and Food Science at BYU, we have conducted research on long-term storage of food. We have collected samples of dry food stored in No. 10 cans for up to 30 years at room temperature or cooler. So far, we have following food products: powdered milk, rice, baking powder, instant potatoes, dried apples, all-purpose flour, pasta, pinto beans, wheat and powdered eggs.

From this testing, we can generally conclude that if properly packaged and stored, all of these foods store fairly well, except for the powdered eggs. In general, the vitamins we have measured (thiamin, riboflavin, vitamin C, vitamin E) in properly stored foods are fairly stable over time. If you think your food storage is getting too old, the best test would be for you to try a sample and decide if it is edible to you. Some people are more picky than others about the food they eat.

What is the nutritional value of basic food storage?

A year supply of basic food storage (400 lb wheat, 60 lb dry beans, 60 lb sugar, 16 lb powdered milk, 10 qt oil, 8 lb salt) provides adequate calories but is lacking in calcium as well as vitamins A, C, B12, and E. Vitamins A and C can be found in canned or bottled fruits and vegetables as well as in some fruit drink mixes. Most vitamin C is destroyed during dehydration of fruits and vegetables, but some vitamin A remains. Good sources of vitamin A include canned pumpkin and dehydrated carrots. Vitamin B12 comes from animal sources and can be found in canned meats and jerky. Calcium comes mainly from dairy products such as powdered milk, hot cocoa mix, and pudding mix (containing dried milk). Vitamin E is found in fats and oils and can be found in nuts such as sunflower seeds and almonds.


We recommend our Food Calculator as a resource for determining how much food is required per person. You can utilize this tool to identify Grains, Legumes, Fats, Oils, Sugar, Milk, Vegetables, Water and Cooking Essentials.