Complete Guide to Mylar Bags for Food Storage

Mylar bags used in food storage have revolutionized the way that food is stored long-term.

The main ways that food is affected by long-term storage is through heat, light, moisture, oxygen, and rodents.

Mylar bags help in all areas of these, although they do not replace a proper food storage container like food grade storage buckets.

However, when used in conjunction with oxygen absorbers and food grade storage buckets mylar bags provide numerous benefits to keep your food safe for many years to come.

Mylar Bags For Long-Term Food Storage

What Is A Mylar Bag

First and foremost, the term “Mylar” is actually one of many trade names for a polyester film called BoPet film.

For the technically inclined and the curious, that stands for “Biaxially-oriented polyethylene terephthalate”.  

This film was developed by DuPont in the 1950s and was first used by NASA for mylar blankets and long term storage as it increases the shelf life of food by eliminating oxygen. Think superpowered aluminum foil.

Since then, many uses for Mylar have been embraced due to its high tensile strength and its moisture, light, gas and aroma barrier properties. 

Mylar is also a good insulator against electrical disturbances, which is why it is used for making emergency blankets.

For all of these reasons and more, Mylar bags are considered the gold standard when it comes to long-term food storage.

Benefits of Using Mylar Bags

Oxygen Protection

Regular plastic bags and Ziploc plastic bags in seeps oxygen back into food products and does not provide any light protection compared to Mylar Bags.

Oxygen and sunlight can cause discolouration, loss of taste, compromise product freshness and allow insects to breed.

Mylar Bags provides an effective oxygen barrier to help preserve your food longer while maintaining its freshness.

The thicker the Mylar Bag, the lower the oxygen transmission rate.

Light Protection

Some types of food are more sensitive to light.

When exposed to light, the temperature of the product can increase. Oil based products such as nuts, biscuits, crisps, and chocolate will be more vulnerable to rancidity and discolouration.

Mylar Bags that are 4.0 and above can completely block out light.

By keeping light out, the product can stay cooler and reduce the risk of rancidity.

Odour

Most foods absorb odour, which affects the taste of food products and the viability of your food storage.

Plastic and paper absorb odour which can affect the quality of your food storage.

Mylar bags are laminated to aluminum which creates an oxygen barrier that prevents contamination against odour and gases.

Moisture Protection

Moisture can destroy your food when in storage.

Dampness created by moisture can cause mould, fungus, insects, and bacteria to thrive and negatively affect your food.

Mylar Bags are laminated in several layers with aluminum foil and are waterproof.

Food stored in a properly sealed Mylar Bag would remain completely dry from any external water sources.

Why Use Mylar Bags In 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.

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 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!

What about Vacuum Sealed Bags vs Mylar Bags

Vacuum seal bags, such as those for the FoodSaver are a wonderful convenience and easy to use.

But alas, they do not have the thickness nor the strength of Mylar bags and they may start to leak after 3 or 4 years.

That said, they are still a great alternative for your short-term and mid-term storage items, especially if you are diligent about rotating foods and using them for your normal meal preparation activities.

Just be sure to include an oxygen absorber if you plan to store your vacuum sealed bags for longer than a year.

The combination of an oxygen absorber and vacuum make for a better long-term food storage option.

Mylar Food Storage Bags

How Long Will Food Last 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 is what you can reasonably expect in terms of shelf-life for foods in Mylar bags.

What Are The Benefits of Using Oxygen Absorbers

Oxygen can be detrimental to food because it oxidizes complex fats, carbohydrates, and proteins.

Oxygen supports the growth of microorganisms and causes discolouration and rancid odours to occur in packaged foods.

Oxygen absorbers are an essential component of any long-term food storage plan because they will continue to protect your goods throughout the time your food is stored.

Oxygen absorbers work in a two-step process by eliminating the initial amount of oxygen in your mylar foil bag while continuing to keep oxygen levels below 0.1% during the time that your food is stored.

Oxygen absorbers effectively reduce the aerobic environment thereby preventing aerobic bacteria and fungi from growing.

Using oxygen absorbers can drastically extend the life of your food products.

How To Seal Mylar Bags Step-by-Step

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)

How to Use Mylar Bags and Oxygen Absorbers

Step #1

Place the remaining oxygen absorbers in a mason jar for temporary safe-keeping.

Step #2

Place the appropriate number of absorbers on top of your food.

You can place them anywhere in the mylar bag. Make sure to avoid overfilling the bag and only seal the top inch of your bag. This will allow extra space for you to re-seal the bag back up again if you need to open the bag to remove any food.

Just remember to add a fresh oxygen absorber before re-sealing.
Note: Depending on the food you are storing, when using a 1-gallon mylar bag, you may need to use 1 to 2 x 300 cc oxygen absorbers or 1 x 2000cc oxygen absorbers

Step #3

You can seal the mylar bags by using a cloth iron or a hair straightener on high setting if you do not have a hot jaw sealer.

Test
the seal to make sure you are able to properly seal the mylar bag with the correct temperature setting on a smaller bag or scrap of a left-over bag. Before sealing completely, push out as much residual air from the mylar bag.

Seal the remaining portion of the bag up
Note: Oxygen absorbers only remove oxygen, which is roughly 20% of the air inside the bag.

This video demonstrates the process.

Step #4

Label and store. Ensure that all your mylar bags are properly labelled with the contents and expiry date.

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.

How To Seal Mylar Bags [4 DIY Methods]

The trickiest part of using Mylar bags for long-term food storage is sealing them.

Do You Have To Vacuum Seal Mylar Bags?

No. You don’t have to vacuum seal mylar bags.

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).

What Temperature To Seal Mylar Bags?

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

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

Mylar Bag Sealer

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.

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.

3. 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.

4. Home Iron

Can you seal mylar bags with an iron?

Yes. You can seal mylar bags with an 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!

Food Storage Organization

Like all your preparedness efforts, you’ll want to organize everything.

It’s important to know what’s in each Mylar bag or bucket without having to open it up. And you’ll also want to know the exact date you sealed the bag or bucket.

It’s important to know what’s in each Mylar bag or bucket without having to open it up. And you’ll also want to know the exact date you sealed the bag or bucket.

The easiest way to accomplish this is by using a sharpie pen. Mylar bags are easy to write on with a sharpie marker. However, they can smudge if you don’t let it dry.

So my favorite option is to use sticky labels. I use a labeler to help keep all my emergency preparedness tasks organized.

For example, I’ve labeled all my homes utilities for my family. Such as our main water shutoff valve and natural gas shut off value. I realize I won’t always be at home, and my family needs help to know which valves are which in an emergency.

Helps me sleep a little better at night.

Here’s the labeler I own.

How To Print On Mylar Bags

If you’re looking to learn how to print on mylar bags at home, here’s exactly how you can do it.

First things first, you’ll need:

• Mylar bags
• Mylar bag printing machine

It is possible to print directly onto the Mylar with an inkjet printer.

This is a great way to make custom mylar bags.

How To Print on Mylar Bags In 5 Steps

Step 1

Choose the Mylar picture, logo or text that you want to print. This media must be on your computer for this technique to work.

Step 2

Ensure that you have a mylar bag printing machine. The required amounts of ink and color combinations are different from those used in regular paper printing.

Step 3

Place the mylar bag in the frame for printing, which came with it. It’s difficult to jam and print incorrectly if there is no frame. Because they will not clog the printer, mylar sheets don’t need special frames.

Step 4

Feed the Mylar bag into the printer and hit print on your computer.

Step 5

Allow the Mylar to dry fully before sealing it.

Mylar Food Storage Action Plan

And that’s it. If this was all new to you, I bet you’re surprised how easy using Mylar bags can be. You need to invest in Mylar bags, oxygen absorbers, 5-gallon buckets, the food you plan to store, and some of your time.

Then it’s time to put it all together and start your emergency food storage plan

1. Decide which foods you want to store and buy them.
2. Purchase your Mylar bags in the right sizes (1-gallon).
3. Make sure you have plenty of oxygen absorbers
4. Purchase a few 5-gallon food grade plastic buckets
5. Make sure you have a heat sealing device (recommended heat sealer).
6. Have your organizational tools (sharpie, labeler).
7. Add ingredients, add oxygen absorbers, seal the Mylar bags (if using buckets seal after they are filled and in the bucket).
8. Store your Mylar bags in buckets in a cool, dry, safe location for maximum shelf life.
9. Sleep just a little bit better at night.

Take action today because knowledge without action…is worthless.

“Always Be Ready” Max