Fan Question: Vacuum Sealing vs Mylar

One of the long time fans recently responded to a post made where I asked the readers what they wanted to read about. Marie W of Nevada asks “I have been meaning to ask what is the difference between storing in mylar bags with oxygen absorbers vs using a food saver? Can you use the oxygen absorbers in the food saver packs as well? Is one better than another for long term storage?” We are glad you asked, Marie!

Before we get into the details, let’s cover what we are trying to do by using food preservation methods. When you are preserving food, you want to halt the growth of bacteria. Bacteria needs light, oxygen, warmth, and moisture to breed. Freezing takes away the warmth aspect and holds everything in suspension. Dehydrating takes away the moisture. Vacuum sealing and using mylar bags remove the air and give a moisture barrier. Pressure canning removes bacteria by killing it off with heat and then the food is sealed, thus removing oxygen.

Now that we have that covered, let’s dive in!

Vacuum sealers are pretty straight forward. They remove the air (to a certain point anyway) and seal the bag. Done! The bags are clear and have 11.5 mil thickness on one side (the ‘bottom’ textured part) and the other is 3.5mil.

Mylar bags are also pretty straightforward. They come in varying thickness (from 3 mil to 7 mil on a quick search). They are used with oxygen absorbers (also called O2 absorbers) that removes the oxygen inside the bag after being sealed. They are not clear, more of a gray opaque color or silver, depending on which ones you get.

What’s the Difference? Which is Better?

I get asked which one is better often and my reply is always the same: “What are you trying to accomplish?” Neither one is overall ‘better’ than the other because even though they essentially do the same thing (vacuum seal), they are used in different circumstances based on what you are trying to accomplish.

If you are wanting to store pinto beans for 15 years, regular vacuum sealing is not the best option. Over time, these bags will allow air to seep in and re-inflate. Even though the air has been ‘vacuumed out,’ there is still oxygen in the bag. Also, the clear material does not keep the light out which will degrade the quality of food and cause nutrient loss over time, too. You can use O2 absorbers with vacuum seal bags but it seems silly so long as your vacuum sealer works properly. On the upside, vacuum sealed meat can last well over a year in the freezer and be just as good as the day you packaged it. No freezer burn, no wasted money!

Mylar bags, on the other hand, don’t do so well in the freezer long term. I am not saying it cannot be done but generally speaking, most people use mylar bags and O2 absorbers for dried good storage. From personal experience, even the 7 mil mylar bags got brittle in the cold and when shifted around in the freezer, got a hole in it. So, taking that portion out of our equation, let’s assume we are talking about dried goods here.

Like it was stated above, storing pinto beans for 15 years in a vacuum seal bag is not the best option. Mylar bags are the ones you want to use for longer term storage. They are thicker overall (generally speaking) and protect better due to the silver/opaque coating that helps block light. Also, because you are using O2 absorbers, you will remove more air and oxygen from the inside of the bags which increase storage times. They will form a tight brick that can be stored in a cool, dark, and dry place for decades.

Summary

Neither method is better than the other. Both essentially function the same but each is better for certain things. Mylar is best for long term storage of dried goods. Vacuum sealing is also good for dried goods but not for long term (more than a couple years). Vacuum sealing also works well for freezing food, handling ‘wet’ food, and even for keeping survival supplies safe.

Tips and Tricks

• It is not recommended to use O2 absorbers when storing sugar – you will end up with a solid block.
• Be careful when purchasing mylar bags. If the shipper folds them, causing creases and points, it is likely the bags will have holes in them and be rendered useless. This usually happens with 5 gallon bags.
• Use a flat iron for straightening hair to seal your mylar bags with. First, they give a wider seal on it which increases security and secondly, they are much less expensive than buying a ‘mylar bag sealer.’