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Complete Guide to Mylar Bags for Food Storage

When it comes to storing your emergency food stockpile, there are a lot of different methods you can use.  However, the most popular method is sealing food in a Mylar bag.

If you are new to Mylar bags, here is everything you need to know to get started – including step-by-step instructions for packing food in Mylar bags, shelf life, and how to use oxygen absorbers.

What is Mylar?

As one man aptly said in a survival forum, Mylar is

Every prepper’s favorite kind of plastic. I know I have been trying (unsuccessfully) to get my wife to dress in it for years.

I’m not sure how it would work for a dress, but Mylar certainly is a versatile material.  The trade name for Mylar is biaxially-oriented polyethylene terephthalate.  It was originally produced in the 1950s and is used for things like insulation, solar filters, blueprints, and even kites.

Why Mylar is Great for Long-Term Food Storage

As far as food storage goes, Mylar is amazing because it is:

  • Non-porous
  • Impermeable to gas
  • Reflects light
  • Flexible
  • Durable and puncture-resistant
  • Cheap
  • Easy to use

There are certainly other packing materials you can use for long-term food storage, but they tend to have a higher learning curve, are more expensive, or simply not as good as Mylar.

Mylar vs. Vacuum Sealing

Many people confuse Mylar bag storage with vacuum-sealing.  They are completely different processes and get different results.

With vacuum-sealing, you are using a machine like a FoodSaver (Amazon Link) to suck air out of the bag while sealing it. While this does have benefits (like being cheap and fairly easy to do), it isn’t the best option for long-term food storage.

Vacuum-sealed bags:

  • Leak: The plastic bags used in vacuum sealing are porous. You can’t see the little holes but, over time, vacuum sealed bags will allow air to leak through.
  • Don’t remove all oxygen: Vacuum sealing will remove most air (which includes oxygen and nitrogen) from the package. However, some air will remain.
  • Allow light through: The bags used in vacuum-sealing are clear – which is great if you want to see what’s packaged inside, but not great if you want to prevent food degradation from light.

By comparison, Mylar bags will not leak. When used with oxygen absorbers, virtually all oxygen will be removed. Finally, Mylar has a foil layer which blocks 100% of light from coming through.

This doesn’t mean that vacuum-sealing isn’t good for food storage.  Vacuum-sealing can increase shelf life of foods by 3-5 times.  But, when it is long-term storage that you want (5+ years), then Mylar is the way to go.

What Foods Can You Store in Mylar Bags?

Any dry, low-fat food can be stored in Mylar bags.  That means things like:

  • Dehydrated fruits and veggies
  • Flour
  • Grains
  • Pasta
  • Sugar

  • Dried beans
  • Powdered milk
  • Cereal
  • Spices

Remember the key words here are dry and low-fat.  Any food which has moisture in it may start to go bad in the Mylar bag.

The same goes for foods which have fat in them – the fat will cause the foods to go rancid in around 3-12 months.

Not Suitable for Long-Term (5+ Years) Storage

These foods can still be stored in Mylar bags, but you’ll have to rotate through them about every 2-5 years (depending on the food).

  • Whole-wheat flour
  • Pearl barley
  • Brown rice
  • Brown sugar
  • Chips and greasy junk food
  • Granola
  • Dried meat/jerky

  • Nuts
  • Seeds
  • Fresh or wet foods
  • Dried eggs
  • Milled grains (other than oats)
  • Any dehydrated fruit or veggie which is not so dry that it snaps when bent!

Mylar Bags and Botulism Risk

Botulism is usually only talked about in regards to home canning.  However, because the botulism bacteria grows in no/low oxygen environments, it could also grow in Mylar bags packaged with oxygen absorbers.

Botulism requires moisture of 35% to grow.  However, to play it safe, virtually all food preservation guides will say that food must have 10% or less moisture to be packaged in airtight containers with oxygen absorbers. (1)

If the Mylar bag is bulging (a sign that bacteria is growing inside), then don’t eat its contents!

This shouldn’t scare you away from self-storing foods with oxygen absorbers.  Just make sure you aren’t storing any moist foods in Mylar with oxygen absorbers for the long-term.

Some moist foods – such as dehydrated fruits — can still be stored in Mylar bags. They will be fine for the semi long term (such as up to five years).  Home dehydrated fruits and veggies just need to be so dry that they snap when bent.

The good news is that botulism toxin (which causes the disease) can be easily destroyed by boiling for 10 minutes. (2)  Many of the foods which get stored for long-term need to be boiled anyway (dry beans, dry grains, etc.), so this in theory would kill any contaminants.

However, that doesn’t mean you should eat any foods which you suspect are contaminated with botulism.  If the Mylar bag is bulging (a sign that bacteria is growing inside), then don’t eat its contents!

Shelf-Life of Foods in Mylar Bags

When trying to figure out how long foods will last in Mylar bags, you will see a lot of different ranges given.   Here’s why it is so difficult to give an exact number of years that food will last.

1. Nutrients Break Down Long before the Food Goes Bad

Part of the reason for these varying shelf-life dates is because nutrients can break down.  For example, the nutrients in rice may start to degrade after 10 years.  However, the rice will still be safe to eat for approximately 30 years.

2. Mylar is a New Product

The process of checking how long a food will last is called shelf life testing. Big manufacturers are required to do shelf-life testing.  However, aside for a few studies on canned foods, there haven’t been any tests on how long food can last.

Also consider that Mylar is a relatively new product (it was made in the 1950s).  We think some foods will last 30+ years in Mylar, but I don’t know of anyone who actually tested food that they packaged in the 1980s!

3. It Depends on Packaging Conditions

Mylar only protects food from degradation due to oxygen and light.  Assuming that you used oxygen absorbers correctly and properly sealed the bag, you still have to worry about degradation from heat and moisture.

According to the USDA, each 10.08 degree F increase in temperature will half the storage life of seeds.  This applies to other foods too.  So, if you are keeping your Mylar bags in a cool area (such as a root cellar), they will last longer than if stored in a hot area (such as your garage).

With these factors in mind, here is what you can reasonably expect in terms of shelf-life for foods in Mylar bags.

Food TypeShelf-Life (in sealed Mylar bag with oxygen absorbers)
Hard Whole Grains (Dry corn, buckwheat, hard red wheat, soft white wheat, kamut, durum wheat, spelt)10+ years
Soft Whole Grains (Oats, quinoa, rye, barley)8+ years
Professionally-Dehydrated Vegetables10-20 years
Professionally-Dehydrated Fruits*10-15 years
Home-Dehydrated Fruits and Veggies*2-5 years
Freeze-Dried Fruits and Vegetables25 years
Legumes (Beans, lentils, chickpeas, split peas)25+ years
White Rice10-30 years
Brown Rice2-5 years
White Flour10-15 years
Whole-Wheat Flour10 years
Corn Meal5-10 years
Potato Flakes30 years
Pasta20-30 years
Dry Non-Fat Milk15 years
Cheese Powder10-15 years
Powdered Eggs5-10 years
Nuts **1-5 years
Granola1 year
Yeast*3-5 years
TVP10-15 years
Baking Soda, Baking, Powder*30 years

*Sugar, salt, baking soda, and baking powder should be stored in mylar bags without oxygen absorbers. Honey does not need oxygen absorbers.

(Sources: 4, 5)

*Dehydrated Fruits and Vegetables in Mylar Bags

Most dehydrated fruits and veggies usually aren’t suitable for long-term storage.  They simply contain too much moisture.

Many people report that their dehydrated fruits/veggies last much longer than 5 years.  However, it’s important that they have very low moisture (10% or less) before storage. That means the fruit/veggie will snap when bent.

Some people also recommend using a desiccant to remove moisture from the dehydrated fruits/veggies before packaging.  More on this later.

**Nuts and Seeds in Mylar Bags

Putting nuts and seeds in Mylar bags will extend their shelf life.  However, because they contain so much oil, they will start to go rancid.

Most people put the shelf life of nuts/seeds in Mylar at about 2 years.  However, some nuts and seeds will last longer than this even outside of a Mylar bag.  The key is keeping the temperature low.

Since nuts are so expensive, I wouldn’t want to risk having an entire batch get destroyed. Only package as much as you actually eat and rotate through them regularly!

Removing Oxygen

Mylar bags only work for long-term food storage if the oxygen has been removed from the bags.  To do this, you need to use oxygen absorbers.

Oxygen absorbers are little packages containing iron.  When you put the oxygen absorber (OA) into an airtight container, the oxygen molecules “stick” to the iron.  OAs can reduce the amount of oxygen in a container to less than 0.01%. (6)

Keep in mind that air is about 78% nitrogen, 21% oxygen, and about 1% other gases.  Oxygen absorbers only remove the oxygen. The nitrogen will remain, thus you often won’t get a vacuum seal.  However, nitrogen does not cause food to spoil.

Note that not all foods are oxygen sensitive.  For example, whole grains, peas, and beans aren’t too sensitive to oxygen.  If you plan on using the foods within 5 years, there won’t be too much difference in freshness regardless of whether you use an OA or not.

However, oxygen absorbers do protect against pests and have other benefits.  Since OAs are pretty cheap, it is smart to use them anyway.

Benefits to Using Oxygen Absorbers:

  • Keeps food from degrading due to oxidation
  • Prevent mold and bacteria from growing on the food (mold and most bacteria require oxygen to grow)
  • Preserve flavor
  • Prevent vitamins from being destroyed by oxidation
  • Kill pests (tiny pest eggs which are invisible to the eye may be on your food; without oxygen they cannot hatch)

Foods which Should NOT Be Stored with Oxygen Absorbers

  • Salt: Will become rock hard if stored with an OA
  • Sugar: Also will become rock hard; brown sugar also contains too much moisture for storage with OAs
  • Wet foods: Foods with moisture of 35% or more can grow botulism in airless environments. To play it safe, it is recommended that foods stored with OAs have 10% or less moisture.
  • Baking soda, baking powder, pancake mixes, and yeast: There’s some debate about whether OA can be used with these foods.  Some claim that a chemical reaction could occur and result in the leavening products then become useless.

Oxygen Absorbers vs. Gas Purging/Nitrogen Flushing

I’ve recently come across many guides and videos about gas purging (aka nitrogen flushing) Mylar bags.  The basic idea is that you use a special machine to force nitrogen gas into the package.  The nitrogen flushes out any oxygen. Then you seal the package so only nitrogen remains.

Nitrogen flushing is used by some food manufacturers to keep their greasy foods (such as chips) fresh for a long time.  That’s why bags of chips are puffy when you get them.

However, unless you have access to professional equipment, nitrogen flushing is very difficult to do! You have to displace all of the oxygen and make sure none gets back into the bag before you seal it.

Packaging with oxygen absorbers is much easier, and leaves just nitrogen in the packaging.  Don’t mess with what works – use oxygen absorbers for your home food storage and leave nitrogen flushing to the experts. (7)

How Many Oxygen Absorbers To Use?

Here is where things can get confusing: For food storage to be successful, you need to have enough OAs to absorb all of the oxygen in the Mylar bags.

Oxygen is in the Mylar bag in two ways:

  1. In the space between the food
  2. Inside the actual food

To figure out the correct amount of OAs you can do some tricky math or just use our handy graphic and table instead. (I have included the math in a dropdown for those who are interested)

As Fresh Pack points out, there can be a surprising amount of oxygen within the actual food. For example, dry foods like TVP contain a lot of air inside of them.  The same goes with dry beans.

They also point out that there is mistaken information about how density affects air amount.  The idea that “items with small particles (like flour) are ‘dense’ and have less air volume” is FALSE.  Here is why:

“A pool filled with marbles will have the same interstitial air volume as one filled with basketballs. Yes, the basketballs will have much larger pockets of air, but there are far fewer of them. Think of a checkerboard with just 2 large black squares and 2 large white squares… ½ of it’s area is black and ½ white. What if it had 100 small black squares and 100 small white ones? 1000? Even with tiny squares it is still ½ black and ½ white as long as the squares are all a uniform size.

What does matter is particle size distribution, or in other words, whether you have particles that are all a uniform size or if you have a lot of particles of different sizes. If you have a pool filled with basketballs AND marbles, the marbles can fill in all the large pockets of air. So, products with uniform particle sizes will have more interstitial air than products with a greater distribution of particle sizes.”

Calculating How Much Air is in the Container

To figure out how much air will remain between the food spaces in a filled Mylar bag, you can do this test:

  1. Put 1 cup of product in a large measuring cup.
  2. Add 2 cups of water.
  3. See how many cups you get total (the amount won’t be 3 cups because the water is filling in the spaces between the product).
  4. Calculate: 3 cups – (how many cups total you got)
  5. The answer is how much of the product was air. For example, let’s say that you got 2.5 cups total: 3 cups – 2.5 = 0.5 cups.  Since 0.5 = 50%, that means 50% of the product was air.

With this information, you can do a fairly exact calculation of how many oxygen absorbers you need.  This requires some more math:

  1. Figure out how much air your Mylar bag holds. For example, a 1 gallon Mylar bag holds 3785 cubic centimeters (cc’s).
  2. Determine how much air will be left in the bag once filled by product. For example, if you determined that 50% of the product was air, then you’d have 1893cc of air space.
  3. Only about 21% of air is actually comprised of oxygen (the rest is mostly nitrogen). So, calculate 21% of your air space.  For example: 0.21x1893cc= 398cc.

*Some products like beans contain a lot of air inside of them.  For the water test to work, you have to let them sit for at least 6 hours so they absorb the water. Note also that beans require a lot more oxygen absorbers than typically shown in charts.

Top Tip
It is always best to play it safe – use more oxygen absorbers than you think you need!  Using extra oxygen absorbers won’t impact the food. OAs are cheap,  better to  spend an extra 25 cents on an additional oxygen absorber than throw away 5 gallons of food when it’s needed most.


Food Type1 quart1 gallon5 gallon
Beans, lentils, split peas125-150cc500-600cc2500-3000cc
Instant mixes and powders100cc400cc2000cc
Coffee beans100cc400cc2000cc
Instant potatoes125cc625cc2500cc
Whole grains (barley, corn, wheat, oats)125cc625cc2500cc

How to Save Unused Oxygen Absorbers

The moment you take oxygen absorbers out of the package, they will start to absorb oxygen. You must work quickly!

The moment you take oxygen absorbers out of the package, they will start to absorb oxygen. After around 2-4 hours, they’ll have absorbed their maximum capacity of oxygen.

It is important that you have a plan on what to do with any unused oxygen absorbers before you begin working.

Ideally, you will reseal oxygen absorbers in the packaging they came in.  Then you vacuum seal them.

If this isn’t an option, you can also store unused oxygen absorbers in a mason jar.  Fill up any extra space in the jar with marbles (or something similar).  The less air that is in the jars, the less air the unused OAs will absorb.   Be sure to seal the jar tightly!

How to Tell If Your Oxygen Absorbers Are Still Good

If you buy OAs from a reputable company, they should be good. We like the supplier DiscountMylarBags, they are the cheapest around and provide good quality products. They also sell on Amazon if you prefer to shop there)

They will arrive in a vacuum-sealed package.  Most oxygen absorbers have a “margin for error” added into their abilities (DiscountMylarBags use ShieldPro absorbers they absorb 200 to 300% of their rating).  So, they will actually absorb more than specified.  This is so you can have a good 10-20 minutes to work with the OAs and not have that air exposure count against you.

Here’s how you can check:

  • They arrive in a vacuum-sealed package.
  • The oxygen indicator is pink or red and not blue.
  • The packets feel soft and not crunchy.


Sealing Mylar Bags

The trickiest part of using Mylar bags for long-term food storage is sealing them.  They must be sealed with heat in order to create an air-tight seal.  Even the Mylar bags with zip seals still need to be heat sealed (the zip is just there for convenience).

You need a temperature of around 375-425 degrees F to get a good seal. Thicker Mylar bags will require a higher temperature.

There are 4 main ways that you can seal a Mylar bag:

1. Clamshell Heat Sealer

This is by far the easiest way to seal a Mylar bag.  They are great because they are hand-held.  They also squeeze, which helps grip the bag.

It makes it very easy to close the last 2 inches of the Mylar bag after you’ve squeezed out the air.

This clamshell sealer is a bit pricey, but it is very easy to use.

It has two heat settings.  The higher one is 410F, which is perfect for sealing Mylar bags.
Check On Amazon

2.  Impulse Sealer

I personally wouldn’t recommend impulse sealers.  Not only are they expensive, but they are designed to seal an entire bag at once.

Ideally, you should seal most of the Mylar bag, push the air out, and then seal the last 2 inches.  This takes some practice with an impulse sealer.

There are some affordable impulse sealers available which get good reviews. For example, this one by Metronic is well liked and doesn’t cost much.

Check On Amazon

4. Hair-Straightening Iron

While I personally don’t have experience using one of these for sealing Mylar bags, it seems like it would be better than a normal iron.  You’d be able to keep the bag vertical so bits of product don’t get into the seal area.

Just make sure you get a hair-straightening iron with adjustable heat settings.  This one, for example, gets up to 450 degrees F at the highest setting.

Check On Amazon

3. Home Iron

If you’d rather not buy a special product for sealing your Mylar bags, a home iron will work.   You’ll need to have a piece of wood to put the Mylar bag against while sealing.

Also be warned that, since you’ll be sealing the bag as it lies horizontally (as opposed to being able to keep it vertical), you might end up with bits of product shifting into the area you are trying to seal.

It’s not impossible to do. However, it can be a bit frustrating – especially when you are trying to work fast because of the oxygen absorbers!

This video demonstrates the process:

Step-By-Step Instructions

Materials Checklist

  • Food that you will be storing
  • Mylar bags
  • Oxygen absorbers
  • Bucket or container (that you will be putting the Mylar bags into)
  • Sealer (clamshell sealer, iron, hair straightening iron)
  • Work gloves

  • Piece of wood with a towel wrapped around it (to serve as an ironing board if using an iron for sealing)
  • Scoop or funnel
  • Permanent marker for labeling
  • Mason jar (or other way to store unused oxygen absorbers)

Step 1: Preparation

It is really important that you get everything set up in an assembly line.  You can take your time filling up the Mylar bags.  But, once you open those oxygen absorbers, you need to seal them quickly!

  • Open Mylar bags and put each in a bucket/container
  • Line up the containers
  • Make sure your sealer has a cord long enough to reach the buckets

*If you are going to put lots of smaller Mylar bags into one bucket, then you obviously won’t be propping up one bag per storage container.  It’s really helpful to have the bags propped up during the process.  Consider rigging a shelf system for holding the bags, or bust out all of your Tupperware to use as holding trays for the open Mylar bags.

Step 2: Loading the Food

  • Using a scoop or a funnel, fill up the Mylar bags with food. You’ll need to give the bags a good shake to ensure the food particles are settled (which means more food per bag and less air).
  • Fill the bags to about 4-5 inches from the top. Make sure you don’t overfill the bag or it will be very difficult to seal.
  • Label the bags and container with the contents plus the date.


  • If you are using 7.5mil Mylar bags, wear gloves! The bags are sharp and can easily slice your fingers!
  • To protect the label from rubbing off, put a strip of clear packing tape over it.

Step 3: Partially Seal Bags

Let your sealer heat up.  Irons and hair-straightening irons need to be on the highest setting. Seal all but the last 2 inches of the Mylar bag. Make sure there aren’t any little pieces of food in the seal.

It is also smart to wear gloves during sealing.  The sealer can make the Mylar bag get very hot and burn your fingers!

If Using an Iron: The easiest way to seal with an iron is to put your 2×4 over the rim of the 5-gallon bucket.  This will make an ironing board so you can seal the bag without having to lift it out or turn it horizontal.  Once you’ve sealed one bag, then just move the board to another bucket.  You’ll definitely want help – one person moves the board and the other does the sealing.
Tip: Make sure you seal as close to the top of the bag as possible.  That way you’ll have room to reseal the bag again.

Step 4: Add Oxygen Absorbers

It takes about 2-4 hours for an oxygen absorber to do its job.  However, you should really try to get your bags sealed as quickly as possible (within 10 minutes, 20 tops).  Otherwise you risk the OA absorbing too much outside air and not being able to absorb all the oxygen in your Mylar bag.
Tip: Before you open your oxygen absorbers, mark each bag with how many OAs the bag needs.  This will speed up the process.

Step 5: Fully Seal the Bag

As soon as you’ve added oxygen absorbers, you need to quickly seal the bag.  Press the bags to get out as much air as you can.  Then seal the remaining 2 inches.

Step 6: Checking the Seal

Wait at least one day.  Then go and check on your Mylar bags.  Look at the seal and see if you can squeeze any air through them.

When oxygen absorbers have done their job, the bag may look “sucked up” or vacuum-sealed.  However, since so much of air is actually nitrogen, it is possible for the bag to be properly sealed but not sucked down.

Step 7: Seal Buckets or Containers

Once you are sure that the seal is good, you can close up your buckets/containers and put them for long-term storage.

Ideally you will store them in a cool place which is accessible during an emergency (for example, you wouldn’t want all your emergency food in the basement during a flood!).

Procedure Graphic (click to enlarge)

Storing food in mylar bags infographic

Which Mylar Bags to Use?

Aside from the brand, there are a few key considerations when choosing which Mylar bags to use: size, thickness, and whether you want zip tops.


Mylar bags come in various sizes, typically ranging from 1 pint to 6 gallons.  To give you an idea, a 1-gallon Mylar bag will hold about 6-7lbs of rice. A 5-gallon Mylar bag will hold about 33lbs of rice.

That’s a lot of rice!

Recommended Reading – How To Dehydrate Food Like An Expert

If you are only doing long-term food storage for your family, you probably don’t need anything larger than 1 gallon Mylar bags.

Yes, you will need more food than this – but it is probably smarter to store the food in smaller bags.

Imagine that a disaster has occurred.  If you opened up a 5 gallon bag of rice, there is no way you could eat it all before the food got destroyed (by water, rodents, etc.).

Also consider how you’d use the food.  Eating 6lbs worth of rice might be feasible, but 6lbs of dehydrated onions?  You’d be much better off putting the dehydrated onions in a smaller bag.

The downside, of course, is that it takes more work to store food in smaller bags. You’ll also have to do a lot more planning to figure out how you’ll divide up the food.

How Much Food Will Fit in a Mylar Bag?

Food Type1 gallon5 gallons
Whole Grain White Wheat5-7.5lbs25-38lbs
Beans (black, pinto, white, etc.)5-7lbs25-40lbs
Potato Flakes2.5lbs12-13lbs
Diced Dried Carrots3.3lbs16-17lbs
Dry Milk5-6lbs29-30lbs
Powdered Eggs4.2lbs20-21lbs

(10, 11, 12)

*How much food you can fit in a Mylar bag depends on a lot of factors.

  • How big the food you are trying to store is (for example, some beans are smaller than others).
  • How well you shake the food to pack it down and how high you fill the bag. It’s easier to seal a bag which isn’t completely full.
  • You’ll be able to fit more food in thinner Mylar bags because they are more flexible.



Mylar bags come in various thicknesses, with 4.3mil and 7.5mil being the most popular.  The 7.5mil bags will hold up against damage better.  However, they aren’t as flexible.

Because the thick bags are so much stiffer, you probably won’t be able to get as much food in them as a thinner bag.

Also note that the 7.5mil bags are sharp! You should wear gloves when working with them so you don’t slice your fingers.

Read our survival glove guide here.

Mylar Bags with Zip Tops

There are some Mylar bags which have zip tops.  The zip top does NOT replace heat sealing.  However, it is great for convenience.

During the sealing process, you can first squeeze the air out and zip lock it before heat sealing.  It prevents little pieces of product from getting into the seal.

Once the bag is open, the zip is also great for closing the bag while you use the contents.

Recommended Products

5-Gallon Mylar Bags with 2000cc Oxygen Absorbers

  • Ten (10) 5-gallon Mylar bags
  • 5mil thick
  • Ten (10) 2000cc ShieldPro oxygen absorbers
  • ShieldPro oxygen absorbers absorb 200% to 300% of their rating

Discount Mylar Bags

Check On Amazon

1-Gallon Mylar Bags with 300cc Oxygen Absorbers

  • Sixty (60) 1-Gallon Mylar Bags
  • 5mil thick
  • Sixty (60) 300cc ShieldPro oxygen absorber packets
  • ShieldPro oxygen absorbers absorb 200% to 300% of their rating

Discount Mylar Bags

Check On Amazon

Handheld Direct Heat Sealer

  • Temperature setting of 410F is perfect for sealing Mylar bags
  • Lightweight and easy to hold
  • Just lock down and hold for seal

Check On Amazon

HSI Hair Straightening Iron

  • Adjustable temperature up to 450F
  • 1 inch plate
  • 8 foot long cord

Check On Amazon

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Leave a comment

    • Yes, you can use a vacuum sealer to heat-seal mylar bags BUT it does a very terrible job! Most heat sealers don’t get to hot enough of a temperature to seal Mylar bags (Mylar is a lot thicker than food-saver bags). It can work okay on thinner mylar, but not on thicker bags.

      On top of that, vacuuming the air out of a Mylar bag while also using O2 absorbers means that the bag can get punctured (especially by sharp things like pasta). Without enough air, the O2 absorber might fail too.

      I know some people do it successfully (usually by making some modifications — there are videos on YouTube). But it’s a LOT MORE EFFECTIVE to just use a hair iron or clothes iron.

      Regardless of how you seal the Mylar bags, you should always CHECK THE SEAL the next day. If it is sealed, then you put the bags into a bucket for long-term storage.

      Good luck and have fun!

  1. Great article! Thank you. This has kick started my education. I feel I can confidently store food long-term after reading.

    I believe one of the tables has incorrect headings. The table “How Much Food Will Fit in a Mylar Bag?” makes more sense to me if the first column is labeled “1 Gallon” and the second column is labelled “5 Gallon”.

  2. Best article I have seen in many years on how to store food in mylar bags. I have only been able to find scattered info and have thrown out many bags because I really didn’t have the info I needed. Your charts are a BIG help. Also threw out bags that weren’t sucked down because I thought the absorbers didn’t work. Never heard anywhere about the nitrogen in the bags. Thanks for a great teaching tool!!

    • Thanks Michelle takes a lot of time and resources to put these big guides together, comments like this keep us going!

  3. What about using Garmin lids and food sealers like the ones for the mason jars cuz that’s what I’m doing and granted I don’t have a big budget but at least I have something that I’m doing in mind when I get the money I am going to buy food containersoners that have the flip top lid and I’m going to put some rice sugar and like you mentioned about rotating that’s how I’m going to do

    • I’m not sure what Garmin lids are. However, it is possible to store food in airtight mason jars. If you want to remove the oxygen from them (and make the food last longer) you’ll have to add oxygen absorbers to the jar.

      I generally don’t think storing food for emergencies/long-term storage is a good idea though. If an earthquake, hurricane, etc. happens, the jars will break. Also, you can’t tell if the seal has broken with jars unless you get ones with special metal lids (the lid will cave downward to show that oxygen has been removed). Jars also take up a lot of space. The Mylar bags and oxgyen absorbers aren’t so expensive, though admittedly it is a slight pain to seal the food in them.

  4. Thank you for the great information.
    The only part I didn’t see was under the heading “How many OE to Use?”. The explanation about figuring out how much oxygen is present is good, but, once I know the ratio, how do I figure out the number of OEs to use by food type, weight & size of bags?
    In your example of “Only about 21% of air is actually comprised of oxygen (the rest is mostly nitrogen). So, calculate 21% of your air space. For example: 0.21x1893cc= 398cc.” how many OEs are needed – 1,2,3?

  5. Thank you for the helpful information. I was able to confidently start my prepping in 1 gl mylar using your article. I can fit 4ct 1gl mylar bags in a 5gl plastic bucket. I then add a gamma lid. I’m very happy with this approach except for one thing. There’s about a whole gallon of air space in my 5gl bucket. I’d like to find make the most of the air space for food storage. Using a 5gl mylar is just too much of any one kind of food for our small family. Do you have any tips on how to make the most of the space in the 5gl bucket?

    Thank you!

    • If your Mylar bags are properly sealed, then air space in the bucket doesn’t really matter. The buckets more about protecting the Mylar bags from damage. However, you could consider putting another small bag of food into the bucket to maximize use of the space. Maybe something that you don’t need lots of at once, like freeze-dried cheese powder, spice mixes, or some sweets? *I actually mixed spices into rice/beans/etc right into the Mylar bag. But, considering how damn picky my children are, I should probably have left the spices separate, haha!

      I know it’s annoying to deal with small Mylar bags but, as you know, the 5 gallon bags are really impractical for most families. Who the heck is going to use up 5 gallons worth of cheese? 😀

  6. Great information and very easy to understand. Many thanks for your research and sharing. I have shared a link to your website with my adult son on the other side of Australia.

  7. How suitable could be to place different kinds of dry food, individually packed in zip lock bags or paper bags inside a 5- gallon mylar bag? How many oxygen absorbers should be required for a 5- gallon mylar bag full this way?

    • That’s a good question. You can definitely package foods in plastic or paper baggies before putting them in the Mylar bag with oxygen absorbers. This will help keep things organized. Just don’t zip plastic bags all the way. While plastic baggies are permeable, it might be harder for the oxygen absorbers to do their work if they need to absorb the oxygen stuck in the plastic bag (this is my educated guess; I haven’t actually tried it).

      I can’t answer how many oxygen absorbers you need. You’d likely end up needing a bunch more because there would be lots of air gaps between the plastic baggies of food. Obviously certain foods would leave less space between them (like bags of flour versus bags of crackers). Oxygen absorbers are cheap so I’d recommend overshooting it. After a few days, see if the bag is sucked-in looking. That’s a good sign that the air has been removed.

  8. I was wondering if using zipped mylar bags that have a CLEAR front or window is a good idea for food in a Bug Out Bag or for backpacking. I was leary about trust them to keep the food safe for very long, not to mention keep animals from smelling the food. If you do think they’re good to use, are there any brands you’d recommend? The ones I’ve found on Amazon seem to be only 2mil or less. I haven’t found any that have a large number of reviews.

    • As you suspected, the zip on Mylar bags doesn’t actually completely seal them. The zip is more to make re-sealing after opening easier. I also find that it’s a heck of a lot easier to seal zip bags: you can push the air out and then zip them before doing a proper seal. As for the ones with clear windows, I would also be weary of them. Just like vacuum bags, they probably leak over time. There are some links within the post to reputable companies. In any case, it’s a good idea to rotate the food in your BOB every 6-12 months. Not only does it ensure the food is fresh, but it gives you a reason to “check in” on your BOB and see if you need to make any changes or replace gear.
      As for animals smelling food, have some rope and hang your food in a bear bag in a tree. Do this even if you aren’t in bear country! While backpacking, I once had friggin’ COWS attack my food bag while it was down from the tree!!! Not to mention all the critters that could get into your food bag. There are also odor-proof bags you can get if you are worried about bears or other dangerous animals sniffing you out while you hike, but you’ll still want to store the food up high.

  9. I’ve spent many days and hours researching mylar bags, and I finally chose the ones from Pleasant Grove. They are 7 mil, and odor proof. I decided for 2 people, the 1 quart and 2 quart zip seal bags will be the best, and most feasible option.
    I also spent a mini fortune on the food grade buckets, with both gamma lids and screw on tops.
    My question, before I spend more money, is it necessary to buy the 5 gallon mylar bags for the buckets, and then store the smaller bags in them? If I’m going to put 2000cc O2 absorbers in the bucket, should this be enough protection? I only found one company that makes those bags with a rounded bottom and you have to buy them by the 10 pack which will cost over $70. All of the other companies use a straight bottom bag, and about 30″ long, and it seems to me that it will be a big pain in the butt to work with.

    • Valerie—Good question. You do NOT need to place already filled/sealed Mylar bags in a 5 gallon Mylar bag AND in a bucket. 1 qt to 1 gal bags go right into the bucket—no 5 gal Mylar needed. The bucket is to protect the 1 qt to 1 gal bags from water, vermin, insects, sharp objects that might pierce your bag(s). Personally, I never use 5 gal Mylar bags. I also mix the contents in my bucket: popcorn, rice, beans, sugar instead of having all rice or all sugar. If an earthquake crushes a bucket, I don’t have all my “eggs in one basket.

  10. You stated in the above length of storage in mylar bags, that sugar and salt are stored with OA. Do not do this as it will become a rock.

    • Thanks for the comment. There’s a section in the article about “Foods which Should NOT Be Stored with Oxygen Absorbers” where we talk about that. I’m going to put a * next to those to clarify that those items in the list shouldn’t have OA when stored. Thanks again!

    • Yes would be ideal for storing peanut butter powder. Not sure on shelf life – the powdered version may be different, but nuts contain lots of oil in their natural state which means they do not store well.

  11. Can you Mylar bag and oa chicken bullion if it’s in a loose powder form but it says it contains dehydrated chicken fat… I got A tub of korrs loose powder but didn’t know if it’s a no no. Thanks


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