Great article!
Any tips on keeping those oxygen absorbers themselves fresh?

Grain in Buckets
The purpose of this article is to present specific details and recommendations for packing your own shelf-stable foods for food storage. We will cover what works and what doesn’t in creating an oxygen-free atmosphere for long term food storage, and common misconceptions about how to do your own packing. While there are many different types of dried foods that can be stored for extended periods of time, most folks are interested in how best to store grain and bean products.
While I could write a book on every specific detail of every packing option and all of the technical specifications of all available packing containers, that is not the purpose of this article. I will cover important highlights, facts, insights, and information gained from over 37 years in the preparedness and outdoor recreation industry. It is important to keep in mind that I have not only been a retailer of preparedness and outdoor foods, I have also been a manufacturer, developer of hundreds of recipes, packaging and product innovator, and researcher of shelf-stable foods.
Some of the material presented here will contradict and challenge information available on the Web or in some do-it-yourself circles. Many people assume preparedness information to be accurate without careful consideration of the source's expertise or the validity of the facts. I encourage you to research on your own any of the information presented in this article – or in any article, for that matter – and to use basic critical thinking skills to evaluate the evidence and data you are offered. A little common sense goes a long way in assessing many of the claims being made about shelf life and do-it-yourself issues.
Before you start packing your foods, be clear about what it is you want to store and for how long. Are the foods appropriate for your plans? Do you know how to prepare them? Do you have an adequate quantity? Do you have all the equipment necessary to prepare your foods? What is the nutritional quality?
This article deals with dry food products with a low to very low moisture content – depending upon the item, this is usually between 2 and about 10%. Products can include grains, beans, seeds, dehydrated or freeze-dried fruits and vegetables, seasonings, and powders and flours.
Grains and beans can be whole or processed into numerous forms. Keep in mind that when a whole grain or bean is processed, it can compromise the integrity of a natural barrier, expose any oils, and begin a process of oxidation or rancidity leading to a shortened shelf life. Some processed bean products, such as TVP (Textured Vegetable Protein), have been de-fatted to insure a longer shelf life, and some grains have naturally lower oil content. Because of the position of the germ in rice, brown rice is not appropriate for long term storage (it has about a 6 month shelf life). Also, because white flour has no wheat germ, it will last significantly longer than whole-wheat flour. Research the products you are storing to determine both the moisture and oil content.
What are the goals and expectations for your food preparedness planning? What are you hoping to accomplish, and for whom, and how many? How realistic are your plans? How long do you want your stored foods to be palatable – edible – nutritious – agreeable? Be honest and make thoughtful decisions about your food preparedness goals.
At the end of this article I have included information on the six critical conditions for storing food. In this section we explore the need for an oxygen-free atmosphere when storing food for long periods. Basically, there are two reasons for wanting to store food in an oxygen-free environment – to eliminate the possibility for infestation from insects and microorganisms, and to control oxidation, which leads to the rancidity of fats and oils, foul taste, off color, and nutritional deterioration. The lower the oxygen levels, the more effective in preserving the integrity of the foods stored.
Some foods are more susceptible to oxidation deterioration than others. It is important to know how susceptible the foods you are storing are to oxidation, because as you will see, the type of container you store your foods in may at some point no longer be an adequate oxygen barrier. Research by Mitsubishi Gas Chemical Company, the inventors of oxygen absorbers and manufacturer of the Ageless® brand absorber, indicates that in an oxygen-free atmosphere (their absorbers can reduce the residual oxygen level in the proper container to 0.1% or less), all adults, larvae, pupae, and eggs of the most prevalent dry food insects are killed within 14 days.

If oxidation and elimination of all stages in an insect’s development by eliminating available oxygen is not an issue, there are other methods that can be utilized with varying effectiveness in controlling insect infestation. Options include:
(Also see the very informative article Using and About Oxygen Absorbers.)
Pro:
Very effective in reducing residual oxygen levels – in my opinion, it is the most effective technology available today
Relatively inexpensive and easy to use if done properly
Harmless components – iron oxide
Easily obtainable
Con:
This product was developed for use by professional food companies that understand how to properly use and store it. There are important guidelines which must be followed for the absorber to work properly and not lose its effectiveness. The do-it-yourself person will defeat the purpose of using this technology if the guidelines and instructions are not properly followed. It is imperative that the absorber user obtain all necessary information from a qualified supplier on its correct use. (Using and About Oxygen Absorbers)
Pro:
Con:
(NOTE: Before the days of the oxygen absorber, companies such as mine used elaborate equipment designed to draw a vacuum and nitrogen flush in a chamber. The goal was a residual oxygen level of 2% or lower, because this was the military specification for long term storage of foods in a #10 size metal can. Even with the proper equipment, reaching these residual levels required experience, testing, and effective methodology. Can “wanding” by hand achieve these levels?)
There was a time (and there may still be) when folks would put dry ice at the bottom or top of a container, leave the lid slightly ajar, wait for the ice to evaporate, and then seal the lid. This method has so many problems that I won’t bother to give it pros and cons. It is not recommended.
Pro:
Con:
You can do your own canning of your own product in #10 metal cans. Some canneries will sell you cans and bulk foods. Read the WSID article from Adam about his experience at an LDS Cannery.
Pro:
Con:
Pro:
Con:
Of all the issues relating to packing your own shelf stable foods, the most effective container to use can be the most confusing and misrepresented. As stated in the beginning of this article be clear about what you are storing, how much, and for how long.

5 and 6 gallon round and square sizes with handles are very popular for packing grains, beans, and other commodities in bulk
Pro:
Con:

There are literally thousands of possible combinations of materials and sizes available to create a pouch that will contain food. Normally a food manufacturer or packer goes to a company that specializes in manufacturing pouches and gives the company their specifications and requirements for the specific foods to be packed.
(IMPORTANT NOTE: It is common these days among those who sell empty pouches for food storage, or food already in pouches, to use the term “Mylar pouch.” This is very misleading. By itself, the term can mean anything and it tells you nothing of importance so that you can make the appropriate decisions on what pouch to use. The “Mylar” brand is the registered trademark name of a PET polyester film manufactured by DuPont Teijin Films. They produce hundreds of variations of this polyester resin material. It is a component used in the production of many variations of packaging material. It can be clear or opaque, such as in wrappers for food bars or Mylar balloons that look “metalized” yet contain no foil. Mylar by itself is not an appropriate material for long-term pouched food. Ask your supplier what they mean when they say “Mylar.”)
For those reading this article, the requirements needed are to pack dry foods for the long term. If you buy stock pouches from a distributor, you need to tell them what you plan to put in it and what your expectations are for the long term. You should insist on knowing the specifications (especially the gas and vapor transmission rates) of the pouch and whether they suit your needs.
If you want a pouch that gives you the longest possible shelf life for your foods, you will need a laminated pouch consisting of multiple components and layers. As far as pouches are concerned, one of those layers must be foil (NOTE: All plastics are gas and vapor permeable – some rates are very high – meaning that gases transmit through them very quickly – and some plastics both individually and in combination have slower rates). Only quality foil is a non-permeable gas and moisture barrier – that is foil without microscopic holes)
Ask the distributor the specifications of the pouch; the different components used, not only for barrier properties but also for durability; the transmission rates, if not foil; if foil, its thickness; and the reliability and reputation of the manufacturer.
Pro:
Con:

For food storage purposes, #10 size (about 7/8 gal) and #2½ size (about 7/8 qt) are the most popular and must be used with the proper can sealers. It is possible, if you keep searching, to find 5 gallon square metal cans with a large pressure lid on the top side. These are ideal for bulk food storage, although they may be hard to find (NOTE: I sold these cans packed with foods at AlpineAire Foods about 20 years ago). You also may want to consider clean or new metal garbage cans as a means to store smaller-size foil-pouched foods.
Pro:
Con:

Pro:
Con:
First choice –
Second choice –
I see no point in putting additional oxygen absorbers into the plastic bucket or container in which the foil pouch is placed.
Third Choice –
There are six conditions to be aware of when storing food for emergency preparedness food storage or outdoor recreation. The foods being referred to in this post are shelf-stable, freeze-dried, dehydrated, dried commodities. Optimal storage conditions can also be applied to wet-pack: retort, MRE’s, canned goods, and other specialty longer term wet-pack foods.
This What Should I Do? blog series is intended to surface knowledge and perspective useful to preparing for a future defined by Peak Oil. The content is written by PeakProsperity.com readers and is based in their own experiences in putting into practice many of the ideas exchanged on this site. If there are topics you'd like to see featured here, or if you have interest in contributing a post in a relevant area of your expertise, please indicate so in our What Should I Do? series feedback forum.
If you have not yet seen the other articles in this series, you can find them here:
This series is a companion to this site's free What Should I Do? Guide, which provides guidance from Chris and the PeakProsperity.com staff on specific strategies, products, and services that individuals should consider in their preparations.
Great article!
Any tips on keeping those oxygen absorbers themselves fresh?
our schools are opening their kitchens to teach the public how to can . This is a great community Idea .
FM
Oxygen absorbers use iron powder and water (contained in a clay-like substance) which react with oxygen to form rust (iron oxide), thus removing oxygen from the air. Several key things to remember with oxygen absorbers are:
1). Oxygen Absorbers Add Moisture: Most research on oxygen absorbers obsessively focuses on their ability to achieve extremely low concentrations of oxygen (~0.1%). While impressive, moisture is the single most important variable in determining the stability of stored foods. Small increases in moisture dramatically increase the sensitivity of stored foods to temperature and oxygen. Conversely, storage temperature and oxygen concentration have far less effect on a product with less moisture. Especially at the low end of the moisture spectrum, small increases in moisture (i.e., from 2% to 3%) result in noticeable decreases in quality and storage life.
Oxygen absorber packages always contain more water than is necessary to complete the chemical reaction. This excess water evaporates and is sufficient to saturate the air of even larger containers. See Maekawa, et al. Therefore, be sure to use an oxygen absorber no larger than necessary. Also, strongly consider using a dessicant package together with the oxygen abosrber. Use of a dessicant is always a good idea with dehydrated foods stored in non-hermetically sealed containers.
The lesson: Don't use a larger oxygen abosrber than you need, and consider using a dessicant package.
2). Oxygen Absorbers Do Not Have Magical Properties: Because the water (as noted above) evaporates, oxygen absorber packages only work for a matter of a few weeks. While oxygen absorbers may continue to absorb oxygen for months at normal humidity, they will cease working within weeks in the (hopefully) dry atmosphere of dehydrated food storage Once the water has dissipated, the oxygen absorption stops. Therefore, if your oxygen absorber is in a location where it cannot be expected to achieve contact with all of the oxygen (i.e., a single packet tossed on the top of a 5-gal. plastic bucket full of potato flakes), then it seems likely that a significant amount of oxygen will be left in the middle and bottom of the container. The oxygen absorption figures often given (0.1%) represent what an oxygen absorber is chemically capable of achieving in a container with good air circulation. I would be eager to see research supporting the effectiveness of oxygen absorbers in many of the situations where they are often used by amateur, at-home packers (i.e., a single absorber packet in a 5-gal. bucket of tightly packed food).
The lesson: Several smaller absorbers may be superior to a single larger one for some applications.
3). Freeze-Dried Foods: I would not use oxygen absorbers with most types of porous freeze-dried foods (such as freeze-dried fruits, vegetables, entrees, and meats). Nor would I buy porous freeze-dried foods that had been packed using only oxygen absorbers, for several reasons:
(a) Freeze dried foods (as opposed to dehydrated foods) have millions of microscopic pores. Although freeze-drying is the superior preservation technology, these millions of micropores create an enormous amount of surface area on the interior of the foods. Most of the oxygen trapped in these micropores will never come into contact with the oxygen absorbing material in an oxygen absorbing packet.
For freeze-dried foods, there is much to be said for the nitrogen-compensated vacuum canning process (NOT "nitrogen flushing"), whereby the food is placed into a vacuum chamber, which sucks out almost all of the oxygen from inside of the micropore matrix. Nitrogen gas is then allowed to flood into the vacuum chamber, which is then sucked deep inside the food particles.
The nitrogen-compensated vacuum process is more than "nitrogen flushing," and while it may result in a final interior oxygen concentration of about 2% (as opposed to 0.1% for oxygen absorbers), the process effectively extracts the oxygen from the deep interior of the food particles and replaces it with dry, inert nitrogen gas. The small amount of oxygen remaining will not contribute materially to food degradation in the absence of moisture.
These comments apply only to freeze-dried foods, and only to those which formerly had a high moisture concentration and are therefore very porous. I would be comfortable buying relatively non-porous freeze-dried foods (i.e., biscuits, grains, crackers) preserved with oxygen absorbers.
(b) Oxygen absorbers will add moisture to freeze-dried foods, defeating one of the biggest advantages of the lyophilization process: the extremely low moisture concentrations achieved.
The lesson: I am skeptical of the ability of oxygen absorbers to match the benefits of the nitrogen-compensated vacuum canning process (NOT "nitrogen flushing") in the case of freeze-dried foods. Many cut-rate freeze-dried food manufacturers are cropping up that use oxygen absorbers (because the process is cheap and easy compared to the expensive and heavy equipment needed for a vacuum chamber). I would keep my distance.
Bottom line: Oxygen absorbers are great when they are in their niche. But they are not a panacea and in some circumstances, over-reliance on their abilities or failure to consider their drawbacks can result in a lower-quality stored food product.
Thanks for posting.
I have been storing grains and have used candles to get rid of oxygen:
I put a candle in a small glass jar, light it, and close the grain bucket (I make sure the flame doesn't burn the bucket). The candle burns the oxygen and is automatically extinguished as the oxygen is used up.
Of course this produces water vapor, so I have also included silica gel water absorbers (that turn color from orange to white when saturated, so that I know if I have added enough).
Is there any reason *not* to use candles?
Seems cheap and easy to use to me... (I have used oxygen absorbers too, but have never been quite sure if I did it right... with the candle I can actually see that the oxygen is used :-).
There is one reason: they don't remove very much oxygen.
Normal air contains about 21% oxygen. A burning candle or other fire in a closed container will go out once the oxygen concentration has dropped to about 17% (actually still enough for a human to breathe). While better than nothing, the candle also adds moisture to the air.
Combustion in a closed container at sea level can theoretically continue until oxygen concentration drops to 16%. In practice, a candle will leave between 16%-18% oxygen, and 3% carbon dioxide. Wang, et al., pg. 292.
So, a candle won't make a big difference in terms of oxygen reduction, especially considering that more oxygen will penetrate through the walls of plastic buckets over a period of months. The advantages are probably counterbalanced by the smoke and water vapor.
In your particular case, your real friend is probably the silica gel that you've been adding. Silica gel will keep working indefinitely to absorb moisture that seeps into a plastic container (until the silica is saturated). Lower moisture levels are preservative in themselves, and will also greatly reduce the food's sensitivity to oxygen and heat.
Hello maceves. Since I wrote this article and have extensive experience using oxygen absorbers, I highly recommend you read my article on using oxygen absorbers - http://learntoprepare.com/using-about-oxygen-absorbers/ at my blog LearnToPrepare.com. For your information, I was the person who first utilized oxygen absorbers in the preparedness industry in the early 1990's as a canner of preparedness foods and backpacking meals at AlpineAire Foods - the company that I owned at that time. Feel free to contact me if I can be of futher help.
Thank you.
So the extra ones that I put in a jar last summer aren't good any more?
Join the discussion