When I first started seriously looking into food storage back in the day, I had no clue how to use oxygen absorbers. I just knew they were really helpful, especially for someone like me that always has so much food to store.
Before I learned a little about them, I had serious problems with food degradation.
Thankfully, a friend taught me about the oxygen absorbers for food storage that help you maintain your food’s original flavor, color, and nutritional value. They can also prevent oxidation in vitamins and medicines which means a longer shelf-life.
So, as I learned more about storing food, I quickly learned that using oxygen absorbers to package dry foods you buy in bulk is an inexpensive way to begin basic food storage. But, in order to do so safely, you must know how to use oxygen absorbers the right way.
Below are the basics you need to know about using oxygen absorbers.
Everything You Need to Know About Oxygen Absorbers
I have taught classes on food storage for various groups and have realized that there are some misunderstandings regarding how to use oxygen absorbers safely.
So, I want to be certain that those who choose to follow and trust me to have the information they need. The last thing I want is for my readers to use oxygen absorbers in a way that won’t safely preserve their food.
So let’s jump right in!
1. What are oxygen absorbers?
Oxygen absorbers are harmless little packages of iron powder. They are non-toxic and BPA-free.
They are also used to remove oxygen from the air (which is 21% oxygen, with the rest being mostly nitrogen) when packaging dry foods.
So, when you put an oxygen absorber in an airtight container, the oxygen in that container “sticks” to the iron in the oxygen absorber. This leaves only nitrogen in the air (which doesn’t affect your food). Check out our article about food storage comparison to help you decide next time.
2. Why should I use them?
First of all, an important part of knowing how to use oxygen absorbers safely is knowing why they are used at.
So, there are five main reasons to use oxygen absorbers when packaging dry foods:
- To increase shelf life (up to 30 years for most dry foods).
- Secondly, to prevent mold or bacteria growth in your food. Nothing will grow without oxygen to feed on! Especially when your food is dehydrated or freeze-dried.
- To preserve vitamins such as A, C, and E that are depleted when exposed to oxygen.
- To prevent dehydrated or freeze-dried fruits from browning
- So that flavor will be kept.
- Last but not least, to kill pest eggs that may be found (but too small to see) in your food (usually grains). These eggs cannot hatch/multiply without oxygen.
Most dry foods have a decent shelf life (one to five years), all on their own without an oxygen absorber. So if you plan to rotate through your foods regularly, you don’t necessarily have to use an oxygen absorber. However, if you choose to (and they are quite inexpensive), you gain the above benefits.
Tip: You can also kill pest eggs by putting your food in the freezer for 48 hours.
3. Where can I buy it?
There are many places to buy oxygen absorbers online, but I get mine on Amazon. You can sometimes find them at Walmart but I have noticed not all stores carry them.
4. What type of containers can I use?
Oxygen absorbers are most effective when used in airtight containers.
But these other types of containers should work too if you adjust for the issues that they each have.
1. Foil pouches (often called Mylar Bags)
Mylar bags should be at least 5 ml to adequately protect your food from light, oxygen, and moisture. However, even at 5-7 ml, they are easy to puncture and not even close to rodent-proof. Therefore, they should be used inside of a food-grade bucket or in another rodent-proof container. Two good places to get mylar bags are Discount Mylar Bags and Mylar Bags Direct.
2. Mason jars
Mason jars keep food dry and fresh, can’t be punctured, and are rodent-proof. However, they are not very earthquake (or child/pet) proof as they can shatter. They also do not keep light out, so they would need to be stored away from light.
3. Metal cans with seamed lids (typically #10 cans)
A #10 can keep oxygen and moisture out, cannot be punctured, and is rodent, earthquake (as much as possible), child, and pet-proof. In addition, when I open them, I only have 11-12 cups of food to get through before it expires, as opposed to 90+ cups in a 5-gallon bucket.
But, you have to have special equipment to seal them. This equipment is extremely expensive. I used to be able to rent the equipment from LDS Home storage centers, but they are phasing that out.
4. Food-grade plastic buckets (typically 5-6 gallons) with mylar bags
Plastic buckets are tough to puncture, and rodents, earthquake (as much as possible), child, and pet-proof. However, plastic buckets do not keep oxygen and moisture out as well as the rest of the options do.
As a result, you will want to use them in combination with mylar bags.
In addition, since you will likely need to get into/out of your bucket many times (once opened) to get through all that food, I suggest using them with a gamma lid. Gamma lids seal out oxygen but can be screwed on and off.
Each time you open your bucket, simply check your oxygen absorber to see if it is hard. If it is, it will not absorb any more oxygen. When it is hard, remove the oxygen absorber and throw a new one in before screwing the lid back on.
Note: You can find some airtight plastic PETE containers, but most commonly used HDPE 5-gallon buckets are not completely airtight and will continue to let oxygen through (though in small amounts).
5. Containers not to use
Do not use zip-seal plastic bags or non-PETE plastic containers without a mylar bag.
What types of food can I store with it?
When learning how to use oxygen absorbers, I believe this is the most important thing to consider.
First of all, you can only use oxygen absorbers on DRY foods (10% moisture or less). If you package moist foods using an oxygen absorber, you run the risk of botulism. You should also avoid oily foods.
Some foods obviously contain a lot of moisture–fresh produce, yogurt, cheese, raw meat, etc. But others aren’t quite so obvious.
Dry foods that the LDS church recommends NOT be stored with an oxygen absorber are:
- Brown Rice
- Pearled Barley
- Dried eggs
- Milled grains (other than rolled oats)
- Brown sugar
- Any dehydrated fruit or vegetable not dry enough to snap when bent
Now, you will find varying opinions on this. Some websites recommend storing many of the above ingredients with an oxygen absorber.
Also, there are many “preppers” who will tell you that they’ve stored the above items with no issues – and I don’t doubt that they have.
When I say that you run a risk of botulism, I don’t mean that you will get botulism. In fact, it would be rare. But for me personally, I tend to be very cautious when it comes to my family’s health and the food I spend my money on.
So, I just don’t want to waste that food by packaging it incorrectly as a result, it will kill your food. You wouldn’t want that to happen.
Also, I trust the LDS church as a solid reference when it comes to food storage. They have been recommending food storage to their members for a long, long time, and I trust their research is accurate.
In addition, other foods should not be packaged with oxygen absorbers:
- Leavening agents (baking soda/baking powder) as cans may explode
- Salt/Sugar (they have a forever shelf life without the oxygen absorber and turn very hard with an oxygen absorber)
How Many Oxygen Absorbers Do I Need?
It is very hard to know exactly how large or how many oxygen absorbers you will need. It will vary depending on the container size, how much open space you leave at the top of a container, as well as the density of the food you are packaging.
While you don’t want to waste money using too many oxygen absorbers, it is better to use too many (or one that is a little too large) than too little.
A little extra won’t hurt your food. But, if you use too few or one that is too small, there will still be oxygen packaged with your food. So, you may not kill all pest eggs and/or bacteria, and you may lose more flavor and vitamins.
As a general rule for usage (erring on the side of too much instead of too little):
- For quart containers or smaller, a 100cc oxygen absorber should work.
- Secondly, for containers larger than a quart and up to 1 gallon, a 400 cc absorber should work.
- For containers larger than a gallon and up to 5 gallons, 400 cc’s per gallon should work.
- For 5-6 gallon buckets, a 3000 cc should work.
You can also download the following oxygen absorbers chart, which will tell you how many products will fit in various containers and how many oxygen absorbers to use.
What are the actual steps for using these products?
Step 1: Prepare your containers
Make sure the containers you plan to use are clean and completely dry. Also, make sure the lid is nearby so you can quickly seal the container once you add the food and oxygen absorber.
Step 2: Prepare your food
Make sure your food is free of any debris (common with beans). Then add it to the containers you’ve decided to store it in, but do not put the lid on yet.
Step 3: Set aside a mason jar with lid
This is an optional step, but I find it helpful!
Oxygen absorbers will begin to soak up oxygen immediately when removed from the packaging. A tip that can help is to store any absorbers you aren’t currently using in a tightly sealed mason jar.
Step 4: Open your package
Pull out one oxygen absorber and seal the rest in your mason jar. Add one oxygen absorber to your first container.
Tip #1 – Oxygen absorbers should feel like they have something soft and powdery inside. If you have one that feels hard or chunky, it has already absorbed all the oxygen it is going to absorb–chuck it.
Tip #2 – Oxygen absorbers will heat up as they start to absorb oxygen. So if you are handling one that is warm, that is a good sign it is working. Just seal it up asap! If it gets hot, I would toss it.
Step 5: Seal your container
If you are storing your food in a mylar bag, here is a great video of how to seal them well (hoping to make one of my own soon, but for now, Prep Charley does a great job!)
Step 6: Label
Label your food and be sure you include what is in the container, as well as the date you packaged it.
Step 7: Wait, then check
It can take up to a few days (even a week) for the oxygen absorber to remove all the oxygen in the container.
If you are using cans or jars, everything should be fine. But if you are using mylar bags, you will want to check that your seal is good.
Remember that oxygen absorbers use up oxygen, not air. Air is only 21%(ish) oxygen. This means that nearly 80% of the air will still remain. So, your packages may not look like they’ve been vacuum sealed.
But, there should be a slight reduction in the residual amount of air in the bag (and if you forced as much air out as possible before you sealed it, the package might look vacuum-sealed).
Last but not least, if you do not see at least a slight reduction in the amount of air in the bag, open it, add another oxygen absorber and re-seal it.
Step 8: Repeat
Repeat steps 4-5 for each container you are preparing.
Step 9: Re-seal your product
This step is important because if your oxygen absorbers go bad it won’t matter if you know how to use oxygen absorbers or not!
So, make sure to store your leftover oxygen absorbers in an airtight mason jar. They should last six months to one year. Be sure you check them again before you use them (if they are hard or chunky, toss them out).
Are oxygen absorbers and FoodSaver the same thing?
Many people assume that oxygen absorbers and a FoodSaver do the same thing.
It is important to know the difference when learning how to use oxygen absorbers.
Oxygen absorbers remove oxygen. In fact, they remove essentially ALL oxygen (99.99%) that is required for long-term storage of foods (0.01-0.02 % oxygen left is the safe range).
It’s so-called “substitute” removes air (oxygen, nitrogen, and a little of other things) through a vacuum. It does not remove ALL oxygen.
However, this does NOT mean that the FoodSaver is useless. In fact, it has a lot of benefits. For example, remember those items that can’t be stored in an oxygen-free environment (those with high moisture or oil content)? Well, those items CAN be stored using this kind of product!
And while you won’t get a 30+ year shelf life out of them, you will increase the shelf life by about three-five times.
Using oxygen absorbers vs. Using Silica gel/desiccants?
When I first started working on my food storage, even the term “oxygen absorber” was completely new to me. So, I had no idea that there was another similar little package you could add to your food called a Silica Gel Packet or a desiccant.
Now I know that there are two little packets that do very different things. Unfortunately, many people (like me a few years ago) don’t realize this.
Here is the difference:
- Oxygen absorbers remove oxygen.
- Silica Gel packets/desiccants remove moisture.
However, you can’t use a Silica gel packet to remove enough moisture to safely package moist foods (see list above) with an oxygen absorber.
My favorite use for Silica gel packets is in opened #10 cans of freeze-dried food. Freeze-dried food has had nearly all the moisture removed, and as it sits in an opened #10 can, it will start to absorb moisture from the air.
This changes the texture and can shorten the open shelf life. But throw a few 10-gram packages in the can, and you’ll fix the problem. Just make sure you replace them every few weeks (or more often if you live in a very humid environment).
Silica Gel Packs are also often used to keep ammunition and firearms, silver, tools, and important documents dry as well. They can also be used to dry up a wet cell phone!
86 thoughts on “How to Use Oxygen Absorbers For Food: A Step By Step Guide”
You said to store your unused oxygen absorbers in a sealed canning jar, but could you use a seal a meal to save the unused ones? Also I was a little confused about the mylar bags in the plastic buckets, do you put the oxygen absorbers in the bags and the bucket or just in the bags with the food?
Can a person use the oxygen absorbers from supplement bottles if you just open up the bottle and the absorber is sofe? If you can, how many would you use for a 5 Gallon Food Saver bucket?
I use a lot of supplements and always end up throwing them away.
The little packages in supplement and vitamin containers are not oxygen removers, they just removed/reduce moisture in the bottle so that would not be something you can use for food storage.
I just finished dry canning several foods that are approved for dry canning with oxygen absorbers. Only the all ourpose flour sealed. Not one other item sealed. Will all of my foods need to be redone with new absorbers? I used the same ones to do five different approved foods. All 36 jars of the flour sealed and popped, but nothing else. What can I do now? Virginia
In the LDS chart, that you included in the above article, can you clarify or give a few more examples of “milled grains”?
What about freeze dried potatoes with the dry cheese packets. Will using o2 absorbers extend their shelf life. Thanks
I am fairly new to the vacuum storage world and I would like to store some Keto foods. Can oxygen absorbers be used with coconut flour? I assume that almond flour would be too oily? Also, I wondered whether dried pasta is suitable for vacuum packing and oxygen absorbers?
I have a concern about dried eggs. Freeze drier and your stating no oxygen. Everyone seems to toss in with everything. Learning is hard with so many opinions. Health and safety is the reason many people do this . What is the correct thing ??? Also how do you extend life of flour and other baking goods. If the world gets anymore crazy we all need to smart and safe. Thank you
Hi, Samantha! As I already noted, some foods obviously contain a lot of moisture, but others aren’t quite so obvious. So, I made a list in the article above of dry foods that the LDS church recommends NOT to be stored with an oxygen absorber are. Between those foods are dried eggs, too. Also, one basic piece of advice when it comes to preserving baking goods’ life is to limit their exposure to air.
Hope this was helpful and thank you for reading!
My wife prepared white rice in a mylar bag with oxygen absorbers, and placed those mylar bags inside 5 gallon bucket for safe keeping. We are curious if there is any benefit (or harm) in adding silica desiccant packets (10 grams) to help with any moisture build-up inside the bucket. The bucket will be stored in a dry space. Will the silica interfere with the oxygen absorbers inside the mylar bags which are stored in the same bucket?
Hi, there! That’s a great question, Michael! In fact, you can use both food-safe silica gel packets and your oxygen absorbers together for your food storage. In this way, you are protecting your food from moisture and oxygen. For example, there are many commercial snack companies using both silica gel and oxygen absorbers together. So, you are safe! Keep up the good work and thank you for reading!
We’re do I get list when vacuum sealing when do I put oxygen absorber. I know rice bean what about corn bead mix and pack cake mix mash potoes wee do I get list for food
to store beans and rice- can I re-use salsa, pasta sauce jars, wine bottles, etc? Must I use oxygen absorbers ? I don’t have a vacuum sealer. I don’t need to store for 30 years- maybe 2-4 years. Thanks
A great question, Ann! If you’re planning on canning, you can reuse your purpose-made glass jars and screw bands, as long as they’re in good condition. On the other hand, the metal snap lids are made to be used once. However, the oxygen absorbers are the best solution, always (especially when it comes to long storage periods).
Does that mean that the answer is “NO” as in, do not reuse store-product bottles and jars and wine bottles?
Can you clarify for me?
No you cannot because the seals have been compromised Gloria.
Canning jars and the rings can be sterilized in boiling water and reused but the lids with the sealing part that snaps /pops letting you know you have achieved full vacuum for safe storage cannot so a store bought jar of lets say pickles , once you have opened that seal it will never seal off again.
I always store my flour in a freezer. It’s good indefinitely that way. I always wrap the bags in a trash bag to store.
great option if you have the freezer space to spare. But a 25 lb bag of flour really takes up some room.
Would you use oxygen absorbers or silica packets to store baby formula long term? There are oils in baby formula, but so are there in some dried milks. Baby formula is more expensive, so I don’t want to mess that up. Thank you!
Hi, Christina! Even though the internet says that it is no harm to do that, as long as you keep the silica gel in the little paper sachets it comes in, I advise you to further research the topic. When it comes to your child’s safety, is essential to inform ourselves as much as possible! Also, when you find the right answer, feel free to share it with all of us! It will surely help our other readers, too! Thank you a lot!
I thought it was seasoning so I opened it and poured it into the food. Can I still eat the food?
How do I get the printable cope
My question is: if I take ten – fifteen 5 pound white rice packages, put them inside the fridge for 4 hours in their original packaging then accommodate them inside a 5 gallon plastic bucket in their original packaging using 5 – 7 oxygen absorbers strategically located and then closing the plastic bucket.
The idea may sound dumb to someone who has experience but I need some advice and thank you all: the editor and the public. Good article with bone fides information.
Thank again and God bless you and your loved ones
You need to pierce the original bags so the oxygen can be removed. Just a small 1/2” slit should do.
I would also put the bags of rice into a Mylar bag and seal them with the oxygen absorber. There’s a chart above for the size OA you’ll need. And I can tell you from experience you’ll only fit 5 of your 5 lb bags of rice in one 5 gallon bucket. You may be able to squish in 6 at most.
How do you suggest storing over the counter meds like Aspirin, Tylenol, Benadryl, antibiotics, etc.? I’m assuming solid pill versus liquid gel? Would Desiccants and removing moisture be a better preserver than using O2 absorbers?
Do you have a big boo sack like me?
I have a few questions
I’m prepping and storing pinto beans, white rice and dry dog food in food grade 5 gallon buckets each inside a 5 gallon mylar bags
Can you please answer some questions for me?
God bless you and your family
Thank you so much
Thank you for the great information!
Just started setting aside food.
I just used oxygen absorbers to put flour in Mylar bags. When I first opened the OA package, I immediately took out the number I needed and put the rest in a sealed mason jar. About an hour later I noticed that the inside of the mason jar had condensation on it. Now I am concerned that there is moisture inside the mylar bags I put the flour in. I followed all the instructions above. Help!
As far as I know, it is not safe tu use this oxygen absorbents in powedered food… it creates a bomb. be careful. do a reserach before you try opening these jars.
So what is the most effective way to store flour for the long term?
To properly store flour:
1. Place flour in the freezer for 1 week & this will kill any eggs/insects in the flour. You can use the bag the flour came in or use a zip-lock bag. (I prefer a zip-lock as flour bags are paper & can absorb any ice particles or odors the freezer may have).
2. Your flour can now be safely stored in Plastic, Mylar or glass.
3. DO NOT use Oxygen absorbers with flour. If you are using Glass or thin plastic containers, the stored flour should be kept out of sunlight, humidity or very warm areas (don’t use the laundry room).
Great information! Thank you!
Can I use oxygen absorber in jars of potato chips?
You can use oxygen absorbers with flour no problem. You don’t have to freeze flour or beans or anything else if your using oxygen absorbers. The absorbers take oxygen out so nothing lives. Freezing is only for vacuum sealing. You just gave false info.
Can you advise about storing flour with packets of Silica Gel?
I live in Orlando n I am putting up pintos in sterile dry 1/2 gal mason jars . But after I left them in the oven with beans for 1 hr 50 minutes then placing dry lids on them n they sealed I started seeing moisture in the jar. I I removed restricted n dried n cooked the jars and dried beans in oven again n let cool. I placed in a moisture absorbed then the cooked beans my hen 2 oz absorbers on top n vacuum sealed. Is this safe now for long term?
@Cindy Smith – according to what I have read, the manufacturers state not to put the jars in the oven as they are not designed for the dry heat (canning is a moist heat). The glass jars can develop micro fissures in the glass weakening it and making it susceptible to breakage when canning later, or breaking in the oven. It’s not necessary to do the oven step. You can freeze the beans for about 3 days, then leave them out to get to room temperature before sealing them up. Also, look up “conditioning” after dry canning or dehydrating. It will keep you from sealing up moisture!
When you say oxygen absorbers need to be stored in a tightly sealed mason jar, what is the best way to do this step? Thank you for your help in explaining how to use the oxygen absorbers.
Rosered Homestead (Youtube) has a video on how to do this if you’ve got a foodsaver. You have to have the attachments for the foodsaver to do so. You basically get your jar ready, then tightly seal it with a lid and ban, then seal with the food saver attachment.
I dehydrate my own scrambled eggs and use a little butter in the pan so they won’t stick and grind them up. I put them in mason jars. Do I need oxygen absorbers in the mason jars
While I have seen lots of videos on dry canning, the National Center for Home Food Preservation – (say that 3 time fast, lol) – does not recommend it as they have not (currently) tested it to verify it’s safety. Regular pressure canning takes the contents of your jars to about 250 degrees for a 90 minute (for quart jars) time frame, long enough to kill all kinds of stuff, including botulism bugs. That said, in the various videos I’ve seen state to run your oven at 220 to 245 degrees. I do not know if that is high enough.
With all that being said, once you pull out each jar at a temp of the max I’ve seen (245) – I have NO idea how the packet of O2 absorber will react to that kind of heat.
Personnaly, I would not chance it. Just my 2 cents worth.