Mylar Bag FAQ

What are Mylar Bags?

Mylar originally was a tradename for a polyester film made from stretched polyethylene terephthalate (PET). However nowadays it often is used as a synonym for any metallized plastic film. Mylar bags in a nutshell are metallized plastic bags. A thin layer of Aluminium is sandwiched between two layers of plastic and a bag is made out of it. Apart from high strength, Mylar Bags protect what’s inside from sunlight and prevent the diffusion of oxygen into the bag, and flavour out of it. Thus Mylar Bags are ideal for increasing the shelf life of dry foods.

What kind of food can you store in Mylar bags?

Mylar bags are usually for dried food, like rice, flour dried beans, seeds, nuts, oats, pasta, other dried legumes, freeze dried vegetables or anything else which is dry. Many people normally store these things in thicker walled solid plastic containers with lids. However, sunlight and oxygen will over time destroy many of the nutrients. With Mylar bags you can keep dried foods fresh for an extended period of time.

How much fits into a 1 Gallon Bag?

Mylar Bags are quite common in the US, therefore their capacity is often measured in the imperial unit Gallon.  1 Gallon equals approximately 3.8 litre. When storing food, a one Gallon Mylar Bag has the holding capacity for approximately:

  • 3 kg rice
  • 2.5 kg spaghetti
  • 2 kg macaroni.
  • 3 kg lentils
  • 2.5 kg dried kidney beans

However, these numbers are just a guideline and can vary by brand and size of the food you are filling in.

How can I seal the Mylar Bags?

Sadly the sealing function of most vacuum sealers is not sufficient to seal the Mylar bags properly. There are dedicated sealing devices for Mylar Bags but they are expensive and rare. An easy and cheap way to seal Mylar Bags is with a hair straightener. Personally, I made the experience that I can get the best results when I set the temperature between 190 and 200 degrees Celsius. However, the non-stick properties of hair straighteners can vary by brand. So before you start sealing the Mylar Bags, test your hair straightener at a small corner first, otherwise you could end up with the mylar material sticking to your hair straightener or burning holes into the bag. Irons have also been sucessfully used.

Do the Mylar Bags have a Zip Lock?

No, our Mylar Bags don’t have a Zip Lock. There are Mylar Bags available with it, however they are not used very often. Reason for that is, mylar bags are usually used for long term food storage. Zip lock sealings often have a minor leakage or even can open up over time, nullifying the high diffusion resistance of the Mylar bags and rendering them useless. You always want to properly seal the Mylar Bag with heat, which will securely keep it closed for many, many years.

Do I need Oxygen Absorbers in my Mylar bags?

No, you don’t need Oxygen absorbers necessarily, but it helps. Dried food like rice and pasta you buy in the supermarket can contain insect eggs, which could potentially hatch in the mylar bags. As the name already suggests oxygen absorber will absorb all the oxygen in the mylar bags suffocating any potential eggs, and prevent them from even hatching. An alternative to oxygen absorbers is to freeze the food or several days to kill of any eggs. However freezing will not stop the oxygen that is inside the mylar bag with the food from possibly deteriorating the food over a very long time.

Are Mylar Bags reusable?

Yes, you can use Mylar Bags more than once if you just cut the sealing line off with scissors and dont rip the bag. Just make sure that the bag is super clean, dry and undamaged.

Do Mylar Bags protect food against rodents?

Mylar bags protect your food against bugs and other insects, however rodents like rats and mice will be able to bite their way through. Putting sealed mylar bags into plastic buckets or containers with lids safely protects them from rodents.

How long does Food stored in Mylar Bags last

That is very hard to tell and obviously depends on what type of food you want to store. Many dry foods will last years if the Mylar Bag has been properly sealed, and an Oxygen Absorber added. There are multiple cases of people that opened Bags of Rice that had been sealed more than 16 years ago and the rice was still fine. Of course storing the filled Mylar Bags in a cool and dark place and protected from rodents is a must. The classig Mylar Bag in a Bucket with a tight lid will likely give the best results.

About the author