Putting food in Mylar bags with oxygen absorbers (OAs) is considered the best long-term storage method for dry staples.
Once sealed, the Mylar bag won’t let any air in. And the oxygen absorber removes oxygen from the packaging, protecting food from oxidation. Some foods, like white rice, can even last 25+ years when stored like this.
At first glance, vacuum sealing food might seem similar to the Mylar + OA method.
After all, vacuum sealing also removes air from the packaging. But there are big differences between Mylar bags and vacuum sealing when it comes to food storage.
The Quick Answer:
Use Mylar bags with oxygen absorbers when storing dry foods long-term (2+ years). Use vacuum sealing for shorter-term storage of foods that you will rotate through. Vacuum sealing is also the better choice when it comes to freezer storage or storing moist foods.
Why Mylar is Better than Vacuum Sealing for Food Storage
All of the top emergency food brands package their foods in Mylar bags with oxygen absorbers. This includes brands like Wise, Mountain House, etc. The fact that none of these brands use vacuum sealing should tell you something.
Ultimately, it comes down to these three properties, which make Mylar better for food storage than vacuum sealer bags.
1. Mylar Is a Better Oxygen Barrier
Mylar is a very durable polyester film. It is metalized through a process called vapor deposition, where aluminum is sprayed to its surface. The result is a bag that is almost perfectly impervious to oxygen. Once sealed, no air or moisture is going to get through the Mylar bag.
By contrast, vacuum sealer bags like Food Saver bags are made from a polymer. The material does a good job of keeping air from passing through it, but it isn’t 100%. Over time, the vacuum sealer bags will allow air to pass through.
There is a lot of research from the food industry on vacuum packaging, which proves this:
- This study found that vacuum sealing preserved dry rice better over 18 months than methods like cold storage and polythene bags – but the quality of the vacuum-sealed rice still degraded each month in storage.
- This study found that, after 12 months, the nutrients in vacuum-packaged dry black rice degraded.
2. Blocks Light
Another benefit of Mylar over vacuum sealer bags is that it is opaque and won’t allow light through. Since UV light destroys many nutrients, Mylar helps food last longer in this way. Read more about how to preserve food for years.
3. Harder for Insects to Chew Through
I’ve had Indianmeal moths infiltrate my pantry and can testify to how annoying they are. The moth larvae easily chewed through my vacuum sealer bags. A Mylar bag I had there remained untouched, despite containing whole grains (which moths love).
Of course, Mylar isn’t completely impervious to pests. Rodents can definitely chew through it. This is why you want to keep your Mylar bags of food in a bucket. But Mylar is still definitely tougher than vacuum sealer bags! Read more about how to rodent-proof food storage.
Vacuum Sealing Does Not Remove Air from Inside Food
This is an important difference between Mylar and vacuum sealing that doesn’t get mentioned much. When you put oxygen absorbers inside a Mylar bag and seal it, the OA removes air from INSIDE the food. By contrast, vacuum sealing only removes air from AROUND the food.
Foods like beans and whole grains have a surprising amount of air inside of them. Even if vacuum sealer bags didn’t have leak issues, you’d still have all that air inside the food, causing it to degrade and eventually spoil.
When Vacuum Sealing Makes Sense for Food Storage
Mylar bags + oxygen absorbers are usually the best methods for long-term food storage. However, there are some times when vacuum sealing is the better choice.
Storing Moist Items
Foods that have moisture of 10% or more should never be stored in Mylar with oxygen absorbers. This is because the botulism bacteria can grow in oxygen-less environments. It then produces toxins that can kill you.
Some “dry” foods contain a lot of moisture. For example, store-bought raisins sometimes have moisture levels of over 10% and should not be stored in Mylar with OAs. Cornmeal can also be surprisingly moist. Vacuum sealing is a much safer storage method for these foods.
Foods with lots of oil or fat will go rancid quickly even if stored in Mylar with OAs. Roasted coffee is just one example. For this reason, a lot of people prefer to store coffee in their freezer.
Vacuum sealing is better for freezer storage than Mylar. The vacuum sealer bags will prevent freezer burn. The bag’s transparency works in your favor because you can see the product to check quality.
You could theoretically put foods in Mylar and then in the freezer.
However, I don’t like this idea: when you take the foods out of the freezer (or your freezer dies during a power outage), you could end up with moisture pockets inside the Mylar bag.
These moisture pockets might be wet enough to allow botulism to grow. (Yes. I’m very paranoid about botulism!) Better to just store the items in vacuum sealer bags.
Vacuum Sealing Canning Jars
Vacuum sealer bags will eventually allow oxygen to leak through. By contrast, vacuum sealer jars won’t leak oxygen. The lids are also usually very durable and create a strong seal.
I have yet to see research about whether oxygen will leak into vacuum sealed mason jars. And I’m personally not a fan of glass for food storage because it breaks easily (earthquakes, hurricanes…). However, it may be a good option to store smaller amounts of food in jars.
Some foods are fine to store in vacuum sealer bags, even long-term. This includes foods that will last a long time on their own, even without special packaging. Pasta is a good example.
Unless it is fortified, pasta has very few vitamins or other nutrients which will degrade from oxidation. I’ve come across pasta in a friend’s pantry that was 3 years expired, and it still tasted perfectly fine (yes, I ate it).
Can I Put Oxygen Absorbers in Vacuum Sealer Bags?
Yes, but using oxygen absorbers in vacuum sealer bags will not have much or any benefit long-term. Oxygen absorbers only make sense in completely air-tight packaging like Mylar bags. Vacuum sealer bags will eventually leak air through, thus removing any benefit from the OAs.
Can I Put a Vacuum Sealed Bag Inside a Mylar bag?
No. Aside from being redundant, this is a bad idea. While vacuum sealer bags do leak, they don’t leak much right away. If you put the vacuum-sealed bag in Mylar with oxygen absorbers, the OAs might not be able to do their job. Oxygen will remain in the food inside the vacuum sealer bag and cause it to spoil.
Note: Mylar Also Comes in Small Sizes!
One of the main reasons that people want to use vacuum sealing instead of Mylar is size. Mylar bags are often very large, whereas you can find tiny vacuum sealer bags. The small size is much more convenient for storing foods that you don’t use much of, such as spices.
But Mylar bags also come in small sizes and are easy to find. You can even cut Mylar bags to size. Just make sure to seal the sides and bottom, and you’ve got whatever size you want.
What foods do you store in vacuum sealer bags and which in Mylar? Let us know in the comments section below!