Mylar Bags For Food Storage: Beginners Guide

Mylar bags (MBs) are hands down the best repackaging container for the do-it-yourself prepper. Mylar food storage effectively protects dry staple foods inexpensively. There isn’t a better DIY container for storing dry staple foods long-term.

What Are Mylar Bags? Mylar bags are made from thin layers of aluminum-coated plastic sheets of Polyethylene Terephthalate, PET plastic. NASA first developed mylar to protect spacecraft from the sun’s heat, and it is still used on satellites and spacecraft.

3 Reason Mylar Is Excellent For Food Storage

#1 Mylar Is an Oxygen, Light and Moisture Barrier

Oxygen Barrier

The one thing that sticks out about Mylar above most other containers? It blocks oxygen from entering the food container when sealed.

An oxygen-rich environment in a storage container destroys food via oxidation and allows aerobic bacteria and mold to grow.

Oxygen oxidizes food, changing the flavor, color, smell, and texture.

Food-grade plastic buckets do not protect food from Oxygen.

Foods that are high in fat will go rancid whether the environment is oxygen-free or not. For example, white rice stores 30 years because it is low in fat, and Brown rice has a 6-month shelf-life because it is high in fats.

Light barrier.

Mylar Bags 5mils in thickness or thicker protect food from light oxidation.

Moisture barrier

Mylar seals out moisture. Moisture is a food killer allowing anaerobic and aerobic bacteria and molds to thrive.

MBs also hold moisture inside the container.

Mylar’s ability to hold moisture in the container is one reason foods should contain less than 10% moisture when packaged oxygen-free. The combination of oxygen-free storage and high moisture levels allow anaerobic bacteria like botulism food poisoning to thrive.

#2 Mylar has a high tensile strength

MBs are tough and somewhat puncture-resistant.

If you go, super-thin MBs are translucent, allowing in light.

Mylars’ most significant weakness in food storage is protection against chewing critters. This is why I always use an armor of plastic around my bags. Preferably food-grade buckets with lids, but other plastic containers work.

#3 Mylar is light and flexible

Mylar conforms to the shape of the foods you store and weighs next to nothing.

Thickness of Mylar Bags For Food Storage

The material in MBs is measured in mils or one-thousandth of an inch, A Mylar bag that is 5mils thick is five-thousandths of an inch thick. All things being equal, the thicker the MB, the stronger it will be.

Mylar bags should be a minimum of 5 mils thick when used to store dry foods like white rice, dry beans, and wheat in long-term storage. Thin Mylar lets in light and oxidizes food. If used without a protective container, consider using heavier seven mil Mylar bags. 

MBs typically come in thicknesses from 3 mils to 7 mils and every thickness in between.

When I store dry goods I typically use an 18″x28,” 5.5 mils Mylar bag in a 5 or 6-gallon food-grade bucket with a cheap lid and an oxygen absorber(s). I get most of my buckets and lids at Walmart in the food section, they are cheap and labeled food-grade.

Scott, Ready Squirrel

Test out your newly learned Mylar skills, learn how to store rice in the Ready Squirrel article, “How To Store Rice In Long Term Storage: By the Numbers.”

Chart #1 Mylar Thickness: Common Use By Mils (five thousandths inches)

Bag In MilsCommon Use
1 MILTransparent/ Light oxidation of dry foods in Long-term storage, weak
2 MILTransparent/ Light oxidation of dry foods in Long-term storage, weak
3 MILTransparent/ Light oxidation of dry foods in Long-term storage, weak
4 MILSemi-transparent/ Light oxidation of dry foods in Long-term storage, easily damaged
5 MILProtects food from oxygen, moisture, and light, store inside a protective container
6 MILProtects food from oxygen, moisture, and light, store inside a protective container
7 MILIdeal For Long Term Food Storage/ Store in a lidded food-grade bucket for rodent protection
8 MILSuper Heavy Weight, Expensive, Difficult to seal

Using Oxygen Absorbers With Mylar Bags

Oxygen absorbers remove oxygen from the void area inside a sealed Mylar bag.

Removing oxygen from food storage containers extends the shelf life of certain foods by decades and kills all bugs, eggs, and pupae within two weeks.

See the Ready Squirrel article to learn more, “Don’t Freeze Wheat Before Long-term Storage.”

18 Foods Stored In Mylar Bags With Oxygen Absorbers

Foods low in fat and 10% in moisture or less can be stored in Mylar with Oxygen absorbers. Following is a list of the “Big hitters” in long-term food storage.

  1. Wheat
  2. White Rice (inexpensive comfort food, complimentary or whole protein when eaten with beans)
  3. Dry beans (highest protein content of any seed)
  4. Dry Pasta
  5. Hard White Wheat berries (mild flavor,enough gluten for leavened bread, foundational staple)
  6. Hard Red Wheat Berries
  7. Ancient Wheat (Emmer, Teff, Spelt) Spelt was eaten by Roman Legions, they called it,” the marching grain.”
  8. Rolled Oats (One of the few soft grains that will store 30 years, Oats made up a major part of the Scotch highlander diet. Highhlanders were known for uncommon strength and stamina.
  9. Steel-cut, Irish Oats
  10. Dent Corn (grain corn, not sweet corn)
  11. Flour (all purpose white flour will store a maximum of 10 years, white wheat berries will store 30 Years)
  12. Hard and Soft Grains
  13. Dried Lentils
  14. Split Peas
  15. Popcorn
  16. Powdered Milk
  17. Dry Cereal
  18. Home Freeze-dried food (home freeze-drying is expensive but awesome for preserving a high volume of food like produce from a survival garden or large quantities of meat. Stored oxygen-free most freeze-dried foods will store 30+ years)
  19. Dried Apple Slices
  20. Potatoe Flakes/Dried Pearled Potatoes/other dried potatoes
  21. Dried Onions
  22. Cornmeal
  23. Oat Groats
  24. Oat Bran
  25. Grits
  26. Flax
  27. Rye

Learn More About Oxygen Absorbers, check out the following Ready Squirrel article, Oxygen Absorbers: “Why You Need Them For Emergency Food Storage.”

Foods Stored in Mylar Bags Without Oxygen Absorbers

It is not recommended to use oxygen absorbers with sugar, salt, baking soda, or baking powder.

Use oxygen absorbers with sugar and salt, and they turn brick-hard but are still edible.

Store bulk sugar and salt in a food-grade bucket with a cheap lid, and they will keep indefinitely (forever.)

Baking Soda and Baking Powder may have a chemical reaction with Oxygen absorbers, so avoid using them together.

Mylar is still a suitable storage container for baking soda and baking powder because both are sensitive to moisture, and Mylar is an excellent moisture barrier.

Chart#3 Don’t Store These 17 Foods Oxygen-free

Wet Foods
Any Food Above 10% Moisture Content
Any Food high in fats or lipids, fats quickly turn rancid regardless of whether oxygen is present in the container.
Barley, pearled (high moisture and high lipids)
Eggs, dehydrated (freeze-dried eggs are ok to store oxygen-free)
Whole Wheat Flour (Processed All-purpose white flour can be stored oxygen-free)
Milled Grains, other than rolled oats
Granola (lipids and high moisture content)
Beef Jerky and Dried Meats (Moisture content and possibly fat content are too high)
Nuts (There is too much oil in nuts, they will go rancid regardless of Oxygen-free packaging)
Brown Rice (Too much oil in brown rice, it will go rancid within nine months regardless of packaging)
Brown Sugar
Table Sugar will turn to stone in an oxygen-free environment, but it’s still edible. Store in a plastic food-grade bucket for an indefinite shelf-life.
Table Salt will turn to stone in an oxygen-free environment, but it’s still edible. Store in a plastic food-grade bucket for an indefinite shelf-life.
Baking Soda (May have a chemical reaction with oxygen absorbers)
Baking Powder (May have a chemical reaction with oxygen absorbers)
Dehydrated Vegetables, Fruit and Meat (Home-dehydrated foods contain 20% moisture content or higher)
Chocolate And Chocolate Chips

What Size Mylar Bag And Oxygen Absorber Should I Use?

Following is a basic chart that shows how many cubic centimeters (cc) of oxygen absorption you need for a specific sized container and type of food.

Various food types are more compact, say wheat and rice; others are less compact, say dry beans and pasta.

The less compact foods leave more oxygen in the container, so they need more CC of oxygen absorption.

Keep in mind you can’t use too much oxygen absorption, only too little.

Chart #2 Size of Oxygen Absorber For a Mylar Bag

Mylar Bag SizesCubic Centimeter(s) cc Oxygen Absorption Required
Foods are more compact, less air volume

Cubic Centimeter(s), cc Oxygen Absorption Required
Foods are Less Compact/More Air volume
——————————Wheat, Flour, Grains, White RiceBeans, Dry Pasta
20″x30″ for lining a 5 and 6 Gallon Bucket(s)20002500 to 3000
18″x28″ for lining 5 and 6 Gallon Bucket(s)20002500 to 3000
14″x20″ (2 gal)10001500 to 2000
14″x18″x6″ (2 gal)10001500 to 2000
12″x18″ (1.5 gal)8001200
12″x16″x6″ (1.5 gal) 8001200
10″x14″ (1 gal)400400
8″x12″ (1/2 gal)200400
6″x10″ (1/4 gal)100200
6″x8″ (1/4 gal)100200
Information Compliments of USA Emergency Supply.

Want to know more about Oxygen Absorbers? Check out the Ready Squirrel article, “What is an Oxygen Absorber: Long Term Food Storage.”

Storing Food with Mylar Bags and Oxygen Absorbers: 7 Easy Steps

Step 1: Line A 5-gallon food grade bucket with a 18 x24 Mylar bag

The Mylar method of packaging dry foods is the same for white rice, wheat berries, dried beans, rolled oats, etc.

See chart #2 above, for the proper cubic centimeters of oxygen absorption for specific types of dry staple food.

It’s a good idea to use only food-grade buckets for food storage because it builds redundancy into your survival food system.

Down the road, you may want to re-use the bucket for moving water, pickling, or fermenting fruit or honey for mead.

Leave your options open.

Step #2 Pour the dry food into the Mylar bag

Fill the bag with food but leave an inch of space at the rim. If the food mounds up too high, you’ll have a hard time getting the lid on.

If you are storing big bulk bags of food, it’s much easier if you have all your buckets ready, with Mylar bags, before you start pouring food in.

Another suggestion, try to get someone to help you by holding the bag open. I do most of my oxygen-free packaging by myself and always get rice, beans, and wheat all over.

Step # 3 Drop in the proper cubic centimeters of O2 Absorber(s)

Once your Oxygen absorbers are out of the package, they start scavenging oxygen; you’ll notice they begin to heat up. I suggest filling all of your buckets with food before you start placing absorbers.

Once the package of absorbers is open, put them in a ball jar and place the lid on until you are ready to take an absorber out.

Step # 4 Seal the bag with a household iron

Place the top edge of your Mylar bag over an old 2″x4″ piece of wood or something similar.

Seal the Mylar bag with a clothes iron, a hair straightening iron, or an Impulse sealer/ Mylar bag sealer.

I use my household iron on the hottest setting, which is the Linnen setting. It has worked well for me, and I don’t have to shell out money for an impulse sealer.

My wife was worried about Mylar sticking to the iron, but this hasn’t happened.

You might want to practice sealing an empty Mylar bag before you seal the real deal to get a feel for it. I’m not practicing what I preach, and I just did it first go.

Step # 5 Write the date and food type on the outside of the bag

Once you get going on your long-term food storage, you’ll have buckets and bags everywhere.

To avoid confusion place food information on the bag. At least the food type and the date. (I put it on the bucket too).

Otherwise, you’ll end up staring at a big bag or bucket of food, wondering what’s inside. The only way to figure it out is to open the Mylar bag and expose food to oxygen.

The true prepper would have a well-organized log of everything market out, but I’m just too lazy to do this.

Step #6 Fold the top of the bag into the bucket

Oxygen absorbers are expended within 4 hours; wait for at least this long before gently folding the bag over and placing the lid on the bucket.

Step # 7 Place a lid on top of the bucket and gently pound it around the rim of the bucket with the heel of your hand

You can also use a rubber mallet if it makes it easier to get the lid on.

Because you are using Mylar bags, you don’t have to worry too much about getting fancy lids or expensive buckets. The bucket is just there to protect the Mylar and for the ease of organization.

Most of my buckets came from the paint section at Walmart, and they are marked food-grade. The lids don’t have a rubber seal or anything, but they keep the bucket sealed up.

Can Mylar Bags Be Reused For Food Storage?

Mylar bags can be reused for food storage.

To reuse Mylar bags, cut the top of the bag below the heat seal, wash it out, let it dry thoroughly. Refill, place oxygen absorbers in the bag and reseal it.

Reseal bags as close to the top of the bag as possible.

Mark the bag with the type of food stored inside.

Can Mylar Bags Be Frozen?

Mylar bags can be frozen or stored in the freezer, but they tend to get brittle over time and are easily damaged when moved around in the freezer.

.Vacuum bags are preferred over heavier Mylar bags for freezer storage of wet foods.

Who Sells Mylar Bags?

There are a lot of places to get Mylar bags online but sometimes it’s hard to tell what you are getting. As you know Mylar comes in all shapes, sizes, and thicknesses.

Look for Mylar bags advertised as, “for food storage,” or “for long-term food storage.” If you just look up Mylar bags you’ll find every kind under that sun, many of them won’t be fit for long-term food storage.

Here’s a short list to get you started in the right direction. Remember your looking for bags between 5 and 7mils in thickness. The bags I use most are 5.5 mils thick.

  • USA Emergency Supply
  • Discount Mylar Bags
  • PackFreshUSA
  • LDS Church Online Store: You don’t have to be a member of the church to purchase from them. They sell huge packs of 300cc absorbers for an excellent price. I have purchased quality oxygen absorbers and dry canned food from them.
  • Mylar Bags Direct
  • Sorbent Systems
  • Amazon-See my affiliate link below
  • Walmart
  • Uline

If you are looking for Mylar bags and oxygen absorbers check out Ready Squirrel’s Amazon Affiliate link to check prices. I get paid for beans and bullets out of Amazon’s profit, not your wallet.

Can Mylar Bags Be Vacuum-Sealed?

If you are storing foods long-term, i.e., white rice for 30 years, vacuum sealing is not a great option because it doesn’t remove as much Oxygen as O2 absorbers and it hasn’t been tested like the Mylar and Absorber combination.

Purchase Mylar Bag Vacuum Ready Food Storage bags individually or by the roll. They are readily available at big box stores like Wally Mart and on Amazon.

Mylar bags are superior to vacuum bags as an oxygen barrier, and the correct quantity of Oxygen absorbers (cc) is more effective than vacuum sealing. Overall, Mylar and Oxygen absorbers are exponentially better than vacuum packing for long-term dry food storage.

Chart #3 How Long Will Food Last (Mylar Bags with Oxygen Absorbers)

Food TypeShelf- Life In Years *
Non-fat Powdered Milk15
Dried Eggs10
Dried Beans30
Dried Lentils30
Split Peas30
Dried Macaroni30
Dried Spaghetti30
Corn Meal25 to 30
Popcorn25 to 30
Table SugarIndefinitely
Do not use oxygen-free storage
Iodized Table SaltIndefinitely
Do not use oxygen-free storage
White Rice30 +
Hard White Wheat30 + (wheat berries with the husk removed)
Hard Red Wheat30 + (wheat berries with the husk removed)
Rolled Oats30
Hard Grains30
Dried Potato Flakes20
Dried Whole Corn25