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No. Ziplock bags do not stop oxygen from seeping in over extended storage (Good for the short term, but when you are storing for years, not weeks, it becomes an issue).
 

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There are several problems with ziplocks. First off is the zipper itself. They're not airtight. Secondly, the plastic isn't an air barrier either. Ever squeeze the air out of one, toss it in the freezer, and a few weeks later, the air is back in? That's what you're trying to avoid.

Mylar is an air barrier. Sealed properly, with no pin holes, it tends to keep air out for a very long time.

Remember, if the food storage companies aren't doing it, then it's probably not a good idea to do. If ziplocks worked, they'd use them because of the savings. If vacuum sealing O2 absorbers worked, they'd do it. If vacuum sealing in vacuum bags worked long term, they'd do it. But they don't. They're doing it right, and if we want to make sure we're doing it right, then we pack our foods exactly like they do. Mylar with an o2 absorber, no vacuum.
 

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Plastic bags are not air tight. The plastic is so thin and air will slowly leak into whatever you have stored in them.

I have some magazines coated in wheel bearing grease stored in ziplock / plastic bags. Over time the grease has penetrated the plastic and has seeped to the outside. When I handle the bags, my fingers get a small layer of grease on them.
 

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New to this and was wondering if a vacuum sealing unit can be used for sealing mylar bags?

Also, does anyone have a list that gives shelf life for dried goods that are stored this way?

Thanks!
 

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Definitely "NO" to the ziplocks. I had a 4-lb bag of sugar inside a gallon ziploc(the kind with the plastic slider knob zipper). This was stored in my kitchen pantry for about three months. Opened it up the other day, and there were tiny black insects in the sugar. This was supposed to be a freezer bag! I thought it would make a good seal...obviously not. Oh well, live & learn.
 

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Definitely "NO" to the ziplocks. I had a 4-lb bag of sugar inside a gallon ziploc(the kind with the plastic slider knob zipper). This was stored in my kitchen pantry for about three months. Opened it up the other day, and there were tiny black insects in the sugar. This was supposed to be a freezer bag! I thought it would make a good seal...obviously not. Oh well, live & learn.
Don't you feel that those insects were already in the food, or do you think they entered thru the ziploc?

I have stored many food stuffs in Ziplocs for years. Occasionally I will find that an insect colony will take hold inside let's say some biscuit mix. I have felt that they were already there, as other items even nearby are not affected....
 

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New to this and was wondering if a vacuum sealing unit can be used for sealing mylar bags?

Also, does anyone have a list that gives shelf life for dried goods that are stored this way?

Thanks!
I think the Mylar bags are to thin to work with the vacuum sealer. Most folks are just using a iron and board or hair straightener for sealing the bags.

As far as shelf like of Mylar bags there hasn't been any scientific studies on them that I've seen. Most of us are going by the storage dates for canned goods that the LDS have investigated. Most stuff is good for 30 years but may not achieve that length with Mylar. The longest I've seen for them is 10 years but I think they may be good for longer. The seams being the weak point and eventually allowing air into the food. Mylar just hasn't been around and used for packing to really know how long it'll last.

Here's a link for a quick summary of some of the foods tested.
http://providentliving.org/content/display/0,11666,7798-1-4224-1,00.html

For more complete information and the studies look at one or more of these sites.
http://lib.byu.edu/sites/scholarsar...tics-and-food-science/long-term-food-storage/
http://ndfs.byu.edu/Research/LongTermFoodStorageResearch/ResearchOnFoodStorage.aspx
http://extension.usu.edu/foodstorage/
 
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I bought a good vacuum sealer after losing food due to ziploc bags, but after researching I think mylar will be they way I will go from now on. Since I am a tinkerer and a HVAC tech, I am currently trying several different containers that I can pull a vacuum on to remove all oxygen and moisture a couple of these I have then pressurized with nitrogen back to 5psi from 28psi vacuum. I have had these setting for 6 months now and so far so good none have lost pressure or vacuum. Will keep everyone updated I hope this works. Hopefully this can be a long-term storage option.
 

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From what I've read there's still more O2 in a container using N2 flushing. Unless you have the machinery to actually measure O2 levels down to less then .1% it's really just a guess.

All the methods tried and O2 absorbers are they only things that can get it that low.
 
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Super Moderator and Walking Methane Refinery
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From what I've read there's still more O2 in a container using N2 flushing. Unless you have the machinery to actually measure O2 levels down to less then .1% it's really just a guess.

All the methods tried and O2 absorbers are they only things that can get it that low.
I tend to agree. I keep seeing people trying to reinvent the wheel here. For now, mylar and O2 absorbers are the best technology to removing O2 and keeping it out. When it comes to something as important as food preservation, why improvise a solution that might not work, when there is already an inexpensive solution that is tested and proven?
 

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I tend to agree. I keep seeing people trying to reinvent the wheel here. For now, mylar and O2 absorbers are the best technology to removing O2 and keeping it out. When it comes to something as important as food preservation, why improvise a solution that might not work, when there is already an inexpensive solution that is tested and proven?
I tend to think the #10 cans with O2 absorbers is the best way to go but the canner is expensive. Unless you have access to an LDS cannery, then I'd do that.

For bulk, like the 5 gallon bucket method I do believe the Mylar and O2 absorber is the next best way to get some food put up. Anything else, seems to make it less effective.

Vacuum,and/or flushing with N2 seem to not be as effective, doing these to Mylar seems to not make it better and possibly worse.

All the tests done by BYU have been on #10 cans. Those with very low O2 levels always come out better then the cans that have leaked or were filled with CO2 but still got O2 in them.
 
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Rather than relying on the properties of the container to fight the invading air trying to get in, the container is flushed with nitrogen or packed in a nitrogen environment. As a result the sealed container has the same or slightly higher pressure but with nitrogen and not air. This means that air is not fighting to get in. There is no abhorrence so to speak.

Thus the period that the food remains unexposed to significant concentrations of oxygen is much longer and thus the possible shelf life is longer.

This was a quote from a source on O2 abosbers and nitro-packing, one comment made was thaat all the oxygen had to be removed< in the method I am experimenting with you first vacuum the container removing all moisture and oxygen using a vacuum pump that will generate -30psi (this is the suggested pressure in evacuation of A/C units to remove oxygen and moisture before charging) then refilling the container with nitrogen, I am filling to 5 psi because most methods that I have researched have used an open lid technique to purge with nitrogren. In my method the system is sealed much like an A/C system so that there is no chance of oxygen being reintroduced (except throgh leakage by the container or the seal which is what I am testing for reliability and longevity of seal)
 

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I tend to think the #10 cans with O2 absorbers is the best way to go but the canner is expensive. Unless you have access to an LDS cannery, then I'd do that.
I'm with you on that. It's the most effective, but the least practical. The prices on the canners have come down since I researched them years ago. Back then you could only buy cans by the pallet also. I keep thinking some day I'm just going to take the plunge and get a canner, but money is too short right now to do it.
 
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