Mylar Lined Buckets, Hand Warmers and Pickle Jars in Long Term Food Storage

I put this as a reply in "Deep Pantry for people who like food".
Then I thought, some people might wish to talk about long term food storage and maybe people would have questions about Mylar since its so mysterious and sinister. LOL. Here is the other post.

As promised. Im hear to talk about Mylar and Hand warmers in food storage. Ild like to thank everyone for the warm reception I've received since I stumbled into this site like a drunk bull in a made in china shop. It seems appropriate to do this today on the verge of a major eastern storm. Reports of stores with cleaned out shelves are coming from all over. Though this is just a storm, it shows the vulnerability of our just in time food system and how easily slight disruptions can overwhelm it. A Deep Pantry is your buffer against these shocks. I have a multi layered food storage. It consists of our stored winter veggies and our own canning, Then there is the Stupor Store stuff. Stuff carefully collected at times they were on super sale. Loss Leaders meant to bring people into the store. Ill buy a years worth right then. Mega McStores don't make much money on a guy like me. Some of that is to be used and rotated. Some is for medium term storage. Then there is the long term food storage. Much of that is under the guest bed which is alittle higher than usual. That's because it sits ontop 20 liter plastic pails lined with a majic item called Mylar food storage bags...with handwarmers in them. And food, of course. This is my insurance policy. I'll eat it some time before I die. Im not exactly sure how many buckets I have. That should tell you something. I don't think about it. The job is done. It was relatively cheap. I don't waist any more effort on it. I ignore it. Occasionally I remember its there and it makes me feel all warm and fuzzy.

What is Mylar and what makes it so special? Its basically a heavy duty plastic bag with a thin layer of metal in it. It can be sealed shut by running an iron across it. You have seen it before, probably in a chip bag. That stuff is the cheap arsed stuff. Its also an ecological and economical disaster...but that is some other post. Ours is the survivalist industrial version and can be reused and re sealed as long as it hasn't been punctured. That's all the buckets are really for. To protect the Mylar. Why isn't the bucket enough? Plastic breaths. If you have completely taken all oxygen out of a perfectly sealed industrial food grade bucket It will equalise with the outside oxygen level in less than five years. That's if the bucket seal actually seals at all. That little layer of metal is what stops the air dead.

This gets us on to the hand warmers. The hand warmer are basically low grade oxygen absorbers. Just more convenient. Absorbers is the wrong term. It burns the oxygen in the chemical reaction between iron and charcoal. It doesn't get hot enough to damage food. You wont get the same suck factor as traditional oxygen absorbers but you will get some. 3-4 hand warmers for a food grade bucket. One is enough for a 4 liter pickle jar and is more than enough for regular jars.

That gets me onto those big pickle jars. I call those poor mans mylar. Ive got about a dozen of those filled for long term food storage. They were recycled from delis. Sometimes the lids were too dented up to get a proper seal and those ones get used in the kitchen instead. Ill usually boil up the lid to soften up the rubber and get it on while the seal is warm. If you get a proper seal with the hand warmer inside it, it should pop down within a day or two. If you still have that bulge in the lid, Try again. Then paint them or store in a box if you want to keep light out.

Back to the mylar. It was intimidating the first couple times. Like I had just graduated into some secret handshake survivalist cabal if I just got it right. Now its old hat. Yawn. Because of the less suck factor, I sealed it with the iron, except for 3 inches, tossed the hand warmers in and sucked the extra air out with the vacume hose, then ironed past the hose. I did a demo on this last year at a local free school. I think my cat must have walked on it because it didn't hold the seal. That reminds me. Don't put your pail lid on tight for a few days. They are hard to get off. Give it a few days to a week to be sure that the seal held before hammering down the lid.

I hope this helps. Good luck with the super storm for those like myself in the effected areas. I have no worries about food

There's a lot in that post so let me unpack a little bit and you can tell me if I got it right.

Basically you are saying "plastic buckets aren't so great for long term food storage because they don't keep the oxygen out." And then you are saying "a mylar sack inside a plastic bucket is awesome, but a re-used glass jar with a well-sealing lid also works and is cheap/free." And finally you are saying that if a person "burns" an appropriate number of hand warmers inside the sealed bucket it will absorb the oxygen that got packed with your food. Have I got that right?

What you don't say -- but which you probably presumed everybody reading already knew -- is that oxygen in your food storage container accelerates the deterioration of your foodstuffs, and so getting rid of it is a good thing.

My one question is about those hand warmers. I don't know enough about the iron/oxygen reaction in them (or the reaction of any additional ingredients they may contain, such as solvents or catalysts or fillers) to know whether they have any gaseous reaction products. Do you know if they do? Do they give off carbon dioxide or carbon monoxide or water vapor or anything like that? Or do they just convert iron filings to iron oxide, while sucking the oxy out of the air in the container and leaving behind mostly nitrogen and the other smaller atmospheric components?

I know I could Google that, but I figure you must have looked into it if you are using these in your food.

Yes. You have it. I didn't want to get too detailed as I am a two finger tiper but simply to point people towards where to start looking. For more detail, you should look it up

Lets start with the why part. Regular buckets are just fine if you have a couple years in mind. What we are talking here about is long stable, long term storable which not all food items are appropriate to do. Processed food with oils, bad. Uncracked wheat or rice , good. White pasta, somewhere in-between. Done properly, wheat or rice should last 25 years with the potential of indefinite.

The enemies of food storage are 1, moisture, allowing dormant bacteria to not be so dormant. 2, heat and or light which degrades structure and nutrients. 3, pests. Buckets to deter rodents. Weevle or bug eggs can generally be killed by putting your wheat berries in the freezer for a couple weeks.

But we are here to talk about #4. Oxidisation. Oxygen chemically reacting with your food. I'm not a chemist so I cant help you with the chemistry questions. Another old way to do this is using dry ice. Oxygen being lighter than nitrogen, the oxygen would lift out of the bucket. I'll repeat this again. Oxygen absorbers don't absorb. They slow burn. The combination of charcoal, iron filings and oxygen creates a chemical reaction slow burn. It will burn until the oxygen is consumed. I opened up one pickle jar after a few months...and the hand warmer had a tiny bit of reaction left in it once reintroduced to new oxygen.

I should also point out that regular oxygen absorbers will do a better job. They just come in larger packs so once you open it, you have to use them all right away. Fine if you are doing 10 buckets at a time, set up to seal them fast. Waistful if you are doing one at a time.

Ross Raven wrote:But we are here to talk about #4. Oxidisation. Oxygen chemically reacting with your food. I'm not a chemist so I cant help you with the chemistry questions. Another old way to do this is using dry ice. Oxygen being lighter than nitrogen, the oxygen would lift out of the bucket.

Yeah, I'm familiar with that trick, and comfortable with it; dry ice is frozen nitrogen and nitrogen is very safe and inert and non-reactive with your food. The only problem being that dry ice is hard to get unless you are pretty close to civilization.

There are also some tricky ways of generating carbon dioxide in a food storage bucket, which like nitrogen will displace the oxygen in the bucket.

I was just wondering about the hand warmer trick because a lot of people here are more worried about toxins than I am, and I simply wasn't aware what interesting gasses might be produced by the reaction in the hand warmers, or what-all chemicals might be in the things in the event that one deteriorated for whatever reason.

Wikipedia is helpful on the latter question:

Air activated hand warmers contain cellulose, iron, water, activated carbon (evenly distributes heat), vermiculite (water reservoir) and salt (catalyst) and produce heat from the exothermic oxidation of iron when exposed to air.

A few sources seem to indicate that the warmers also emit carbon dioxide, which would be fine if true. I don't think I'm going to nail it down with a casual Google search, but I think I'd want a firm answer about reaction byproducts before I stored a lot of supplies this way.

I believe someone mentioned about "Perfect being the enemy of good"
I wouldn't cut open the bag and sprinkle it on my breakfast cereal...but whatever trace has got to be better than bicycling around in a city and simply breathing the air. If someone blew second hand smoke on my Wheaties...I could live with that.

Ross, I don't think you and I are in disagreement. My gut -- and the little bit of Googling I did --- is telling me the hand-warmers are nothing I personally would worry about, chemically speaking. But there are people here at Permies who are vastly more careful about the chemicals they ingest than I am. So I figured it was worth exploring. I'm sorry if it came across like an interrogation; I was just trying to draw out of you some information I figured you probably had. No worries!

Ah. Food Taliban are hiding in the bushes. Got'cha. Addiction is a terrible thing. Im not wise enough to help people with that.

Im liking this new catch phrase, "Perfect being the enemy of good". Is it a permaculture dictum? (Insert Han Solo smile here)

Hi all,

I'm currently in the process of vacuum sealing wheat berries and much more in mylars with oxygen absorbers.

As for those skeptical towards plastics and aluminum bags and diverse chemicals in O2 absorbers; mylar bags definitely have a mission for people that do not have a farm to fall back on in emergencies.
Vacuum sealed mylar bags are an excellent alternative for long term food storage. I myself use this solution for substantially increasing my chances for getting through a transition period in case of a grid breakdown, or if you plan going off grid.

Personally I like glass jars best, but mylars have a few advantages in some areas that are worth checking out. I use both alternatives.


As for killing off any potential bugs etc by deep freezing foods, like wheat berries, I would be careful. Because the deep freezing will cause condensation of air in whatever container you put them. This condense moisture will be absorbed by the food and your dried foods may not be that dry after all.
Wheat berries should not contain more than 10% water before they are vacuum sealed. 12-13% is absolute limit if goal is long term storage for grains that HAVE to sprout after 15+ years of storage.

Moisture is some less critical for grains and other seeds that do not have to sprout, but in general the drier the better.

Temperature remains an issue even if stored dark and in a vacuum. The cooler, the longer they will keep.

Seeds that do not sprout can still be cooked or can be used to grind to flour.

As for rice, most would prefer brown rice. The problem with long term storage of brown rice is that it contains too much fat and that will go rancid anyway.
In general you may expect 1-2 years longer storage time if vacuum sealed, but max 4 years for brown rice. As far as I know the same counts for sunflower seeds, milk powder that contains too much fat, nuts etc. Whole Oat berries may also have limited storage time because of higher fat content than Wheat, Rye, Spelt etc.

So be aware of these 4-5 elements, moisture, oxygen, fat, temperature and light, and you'll have quite a treasure if the grid breaks during the next 10-20 years. The only problem with it is that you would look tastier compared to the hungry masses.

Well that is what I remember from studying this subject, and I'm keeping myself to it. There are experienced long term food storage folks available on prepper/politically incorrect websites and that could help with providing reliable data on this topic.

While talking about it.., fats are still a necessity. For short term I keep to good quality olive oil and coconut oil (3-5 years). For long term (10? years) I count on homemade Ghee.

Pickle jars are great, and you can buy new lids from Amish stores for a quarter a piece or so. You can order online, too, but you need to order a lot to make it affordable.

Long term fat is an issue. We have some coconut oil, but long term you need a plan to grow it. Ghee, lard, tallow, sunflowers, soybeans, olives, nuts. You need to find an efficient way for your climate and resources.

I think everyone needs a plan to supply their own fats as part of a Permaculture homestead.