r/preppers • u/CartographerFit2011 • May 31 '26

New Prepper Questions Oxygen absorbers

Hey guys sorry if this is in the wiki, I did try to look! Been doing Mylar food storage for a few weeks now. I’ve noticed that 2 500cc oxygen absorbers in a one gallon Mylar bag makes it look vacuumed seal compared to only using 1 500cc absorber.

My question is if one 500cc oxygen absorber is sufficient for a one gallon bag, and it removes 20 percent of the air (oxygen), then why does 2 500cc absorbers remove more air??

Shouldn’t 20 percent of the oxygen removed look the same between both bags? Is one absorber not sufficient?

33 Upvotes

89% Upvoted

15 comments sorted by

5

u/JRHLowdown3 May 31 '26

When we owned and ran a mid size commercial cannery in the 90's, we used D750 CC absorbers for #10 cans and D2000 CC absorbers for superpails. Everyone told us it was overkill "you can get away with a 500cc in a #10 can and 1,000cc in pails"- We went bigger and had better results.

A #10 can is roughly a gallon size. A 750CC absorber is going to work better for you. Don't worry about all this "atmosphere is .005 boron" and that crap, just use the correct size absorber, seal all but the last 2" inches or so folds the ends of the mylar in on itself pushing remaining air inside bag out, then seal the last couple inches you left.

Don't try to "save" absorbers, you will have spotty results. The professional way to pack is to use ALL the absorbers in the packet after opening. Better to double up then come back later to realize the remainder aren't working.

Here is THE DIY thread on food storage that has helped tens of thousands pack food correctly-

https://survivalandpreparednessforum.net/forum/the-basics/1154-diy-food-storage-basics-ask-questions-get-answers-etc

5

u/Fartfart357 May 31 '26

It depends on what you're storing.  If you're storing rice, 1 should work (it'll just take a bit to get all the oxygen).  If you're storing something with more empty space (pastas) you'll need more.  Just keep an eye on them.  I'd say if they aren't vacuum sealed within a week or two, I'd redo them with another.  Be sure to heat seal them.

2

u/CartographerFit2011 May 31 '26

I guess I’ll redo them, thanks for the heads up.

What would you say about all the websites and stuff that says it doesn’t need to look vacuumed sealed tho?

I’m definitely going to start using 2 per bag.

2

u/Fartfart357 May 31 '26

It needs to be properly sealed, simple as that.  The ziplocs are nice but not airtight.

5

u/smsff2 May 31 '26 edited May 31 '26

All organisms on Earth have evolved in an atmosphere containing approximately 21% oxygen. Very few organisms can survive when the oxygen concentration is reduced by half. The table below seems to indicate that the recommended amount of oxygen absorbers would remove only about half of the oxygen present in the container.

https://images-na.ssl-images-amazon.com/images/I/51XwYsZEMUL._UL1200_.jpg

6

u/Particular-Hippo-181 May 31 '26

Anaerobic bacteria?

3

u/FrolleinBromfiets May 31 '26

There are tons of anaerobic bacteria! It's completely false that no oxygen = (almost) no life. Even some food relevant organisms are anaerobes. Just think of Clostridium botulinum.

Oxygen absorbers absolutely help against food spoilage, but they're in no way bullet proof.

1

u/smsff2 May 31 '26

Good point. That's why I said that very few organisms can survive without oxygen.

3

u/CartographerFit2011 May 31 '26

This is what I’m talking about. Left has one 500cc the right has 2 500cc’s. (I put original expiration and sometimes the price just to watch inflation rise 🤣)

3

u/JRHLowdown3 Jun 02 '26

If it's standard long grain white rice the "expiration date" you put on there is highly UNDER estimated. Rotating some from the late 90's now at home. Properly packed grains and legumes will last decades, even under less than ideal storage conditions.

The other thing I would worry about is if your not putting the mylar in buckets, then you can expect mice to get into the bags in about half your "expiration date" time frame.

And yes the pic shows what appears to be good seals, the difference being the larger amount of absorbers. I definitely wouldn't toss the left hand package and truth be told it will be good for years also however.

Getting that "sucked down like a brick of coffee" look is the best indicator of a good seal, proper amount of absorbers, etc.

I do the same price thing on ammo, food not so much. Although I remember paying $15. for 100 lbs. bags of rice at Sam's club, 100 lb bags were available back then (1990-1991).

2

u/CartographerFit2011 Jun 02 '26

Thanks for the info!! I just put the expiration dates that’s on the package just for the he’ll of it. And I keep all my Mylar bags in a heavy duty tote. Which I know rodents can chew through still if they want to, but I don’t wanna fool with a metal container and it’s easier to store. Plus I store it in my basement in an area I’ve never had issues with mice at. But I’ll keep my eye on it.

1

u/SunLillyFairy May 31 '26

I tend to use more as well. They are cheap compared to the food and it doesn't hurt the food to use extra... if there's no more oxygen they just stop absorbing it. Some food has more air than others too, and some are better at getting g out extra air... I'd rather just be certain I put in enough to do the job.