About Oxygen Absorber

Q: What is an Oxygen Absorber and How Does it Work? 

A: An oxygen absorber is a small packet used to remove oxygen from sealed environments, bringing the oxygen level down to less than 0.01%. 

Unlike silica gel, which targets moisture, oxygen absorbers specifically target air exposure to prevent oxidation, mold growth, and insect infestation.

Most standard oxygen absorbers contain iron powder. When the packet is exposed to air, the iron powder undergoes a chemical reaction—essentially a controlled rusting process—that traps the surrounding oxygen molecules inside the packet as iron oxide.

Q: Why Use Oxygen Absorbers in Shipping and Packaging?

A: When goods are sealed for long-term storage or transit, trapped oxygen causes three major types of damage:

1. Oxidation: Causes oils and fats to go rancid, changes food flavors, and degrades certain plastics or chemical compounds.

2. Aerobic Mold & Bacteria: Most molds need oxygen to survive. Removing the oxygen halts their growth entirely, even if some moisture is present.

3. Pest Control: It eliminates insects, larvae, and eggs hiding in organic products without requiring toxic chemical fumigation.

Q: Why do oxygen absorbers get hot after being opened? Is this normal?

A: Yes, this is completely normal and safe. In fact, it means the oxygen absorber is working exactly as it should!

Oxygen absorbers (deoxidizers) contain iron powder. When you open the outer vacuum-sealed packaging, the iron powder is exposed to oxygen in the air for the first time. This triggers a chemical reaction known as oxidation (essentially a rapid, controlled rusting process).

Because oxidation is an exothermic reaction (a reaction that releases energy), the packet will naturally warm up as it actively pulls oxygen out of the air.

What should you do when this happens?

While the heat is normal, it means the packet is using up its capacity. To get the best results, follow these three steps:

• Work Efficiently: Try to place the oxygen absorbers into your final product packaging within 10 to 15 minutes of opening the main bag. The longer they sit out in the open air, the hotter they will get, and the less absorption power they will have left for your product.

• Reseal the Unused Packets: If you opened a large master pack but only need a few, immediately place the remaining packets into an airtight glass jar or heat-seal them back into a high-barrier foil bag. Once you cut off the oxygen supply, the reaction stops, they will cool down, and they will be preserved for future use.

• Avoid Over-Stacking: When working with multiple packets, spread them out flat on a tray rather than leaving them in a big pile. Stacking them traps the heat, which accelerates the reaction and wastes their capacity even faster.