Oxygen absorbers, also called oxygen scavengers, are chemical mixtures packed in the form of sachets or packets in a plastic film. The chemical ingredient has a chemical reaction with oxygen molecules to form an oxidized compound, removing free-forms of oxygen molecules from the surrounding environment. The chemical mixture in OxyFree® oxygen absorber sachets has an active ingredient of iron powder (Fe) in most formulas. Alternative OxyFree absorbers have an active ingredient of Vitamin C.
Our OxyFree® sachets are completely safe. While they are not edible, they are non-toxic. The acute oral toxicity testing on mice shows the LD50 > 5,000 mg/kg body weight.
In some instances, dogs may swallow an absorber. If this happens, do not panic! Be sure to monitor your pet’s water intake level as he or she may become thirsty. Please visit the ASPCA website or contact your local vet for more information.
No harmful gases are emitted from the OxyFree® sachet. One formula emits CO2 intentionally for certain food applications, but OxyFree® sachets will not alter the smell or taste of the product they are packaged with.
When food is in an environment containing oxygen, even as low as 0.5%, it can spoil or develop mold over time. The food ingredients may become oxidized, causing the color or freshness to change while microorganisms can thrive and alter the desired food taste. By using OxyFree® sachets to maintain an oxygen-free environment, food can keep its freshness, taste and color for a much longer period of time.
Eliminating the need for additives such as BHA, BHT, sulfur dioxide, sorbets, benzoates, etc., OxyFree® oxygen absorbers prevent the growth of aerobic pathogens and spoilage organisms, including molds, while extending the food’s shelf life. Combined with gas flushing packaging to absorb virtually all the oxygen, OxyFree® oxygen absorbers absorb any oxygen that may permeate the package.
You may fill out our inquiry form and we will arrange samples for you.
All of our products are compliant with FDA and EU related regulations.
Avoid exposing OxyFree® packets to open air for an extended period of time. When the master vacuum bag is opened, the iron powder in the sachets will start a chemical reaction with the oxygen from the air and form an iron oxide in the packet, thus exhausting its oxygen absorption capacity. Depending on the type of formula, there is a limited time period that sachets may stay exposed to open air before being applied. In general, it is recommended to apply the OxyFree® sachets within 60 minutes after the master vacuum bag has been opened.
By using OxyFree® sachets, you can extend the shelf life of your food products much longer than gas flushing or vacuum packaging. When an OxyFree® sachet is used with proper packaging and sealing, it can bring the oxygen level down to reliably 0.1% or less in a matter of one or two days. With a high barrier packaging film it can maintain an oxygen free level (<0.01%) throughout the product’s shelf life. Such results are impossible to achieve with either gas flushing or vacuum packaging. First, there is always some residual oxygen (0.3-5% depends on methods and equipment) left in the food package. Second, during the storage of food, oxygen from the air can enter the food package increasing the oxygen level. Over time, the oxygen level continually rises inside of the package. Also, the increased oxygen level limits the shelf life that such methods can achieve.
Select the appropriate formula type and size of the OxyFree® sachet. The food container material must be of a high oxygen barrier. Put the OxyFree® sachet inside the food container and seal the container completely.
First you should select the appropriate type and size of an absorber sachet. The container’s material should have a high oxygen barrier. Put food and absorber inside the container together, including one oxygen indicator tablet and position this First you should select the appropriate type and size of an absorber sachet. The container’s material should have a high oxygen barrier. Put food and absorber inside the container together, including one oxygen indicator tablet and position this indicator in a way so that it is easily observed inside the container. When exposed to air, the oxygen indicator tablet will show blue. When the environment contains no oxygen (oxygen concentration< 0.1%), the tablet color will be in pink. When exposed to air (with oxygen) again, the color will change back to blue. Once the indicator is properly placed inside, seal the container completely.
Absorber packets are vacuum packed inside large master bags. If the master bag loses its vacuum sealing, the packets can possibly slip or move around. If you shake the bag and the packets freely move around in the package, please do not use the packets in this bag. After opening a master bag, you should spread out the needed quantity of sachets in a tray for usage. Please do not expose the sachets to air for more than 30 minutes. The remaining sachets should be resealed in the master bag after removing air from the bag, or using a vacuum heat sealer to seal it closed.

It’s quite simple.

  • Calculate the initial oxygen absorbing capacity. This is the capacity needed to remove all oxygen from a container in the beginning.
  • The formula for a preliminary estimation of oxygen volume in a container is: Oxygen volume Vl (CC) = (container volume (CC) -contained goods volume (CC)) x 20% =~ (Length(cm) x Width (cm) x Height (cm) – food Weight (g)) x 20%.

If this is too complicated, let us know the size of your package (width, length and height), oxygen permeability of the packaging film and the number of days of the product’s shelf life and we will calculate it for you.

You need to plan your production flow in a way that your sachets would not stay exposed to open air exceeding the allowed time period. If, for whatever reason, you have to stop your process (e.g. the shift goes on break or there were unused sachets left over) you need to place the unused sachets, if they were not exposed to open air over designated time period, inside a high barrier bag or the master bag and vacuum pack them with 99% vacuum.
It depends on the OxyFree formula type
  • Type A < 60 min
  • Type C < 20 min
  • Type F < 30 min
  • Type H ET < 3-5 hrs
Oxygen indicators must be stored in an oxygen free atmosphere inside a high barrier bag or hermetically sealed without being vacuum packed, together with 2 or 3 oxygen absorbers.
Yes, this problem is quite easily overcome by using oxygen absorbers in your food applications. With an appropriate type of absorber and a high barrier film, you may forget that this problem ever existed.
Yes, typically this is good enough to withstand a high rate of oxygen permeating the food package.


AIR is made up of mostly Nitrogen & Oxygen.
“Air” is a colorless, odorless, tasteless, gaseous mixture, made up of mainly nitrogen (approximately 78 percent nitrogen) and oxygen (approximately 21 percent oxygen) with approximately 1% of lesser amounts of argon, carbon dioxide, hydrogen, neon, helium, and other gases.

When you put an oxygen absorber of the correct size into a Mylar bag along with food, the oxygen absorber is going to scavenge (aka remove) the oxygen from the bag, nothing else. The bag will still contain all of the nitrogen and 1% other gases, so you will still have 80% of what you were calling “air” inside the bag. What is in the bag now is nearly 100% nitrogen, which is why this process is nearly identical to the much more complicated method of flushing a bag with nitrogen gas from a big tank.

It will most likely LOOK like you still have “air” (oxygen + nitrogen + 1% other) in the bag because the VOLUME of “air” has only been reduced by 21% (the oxygen). But what is in the bag is NITROGEN, not “air” (oxygen + nitrogen).

The oxygen absorber will remove ALL the oxygen and leave ALL the nitrogen, so the chances of all your Mylar bags of foods looking vacuum sealed is slim. It’s just plain physics. If there was a cup of “air” in the bag when you sealed it up with the oxy absorber, then you will have over ¾ of a cup of nitrogen still in that bag after 24 hours, which is exactly what you want.

Occasionally, a mylar bag of dried food with an oxygen absorber of the correct size will appear to be vacuum packed. Vacuum packing is a completely different process than nitrogen packing. Vacuum packing removes most, but not all, of the “air”. Vacuum sealing leaves some “air” (nitrogen AND oxygen) in the bag with the food, which is in a clear single layer plastic bag not designed for long term storage (if you are using a Food Saver or Seal a Meal). It is OK if there is still some oxygen in a vacuum sealed bag because vacuum sealing is for short to mid-term food storage, NOT long-term food storage.

So if your Mylar bags don’t suck down hard the way a vacuum sealed bag does, don’t worry. What is still in that bag is nitrogen, protecting your food for long term storage.