For food packaging OxySorb is USFDA and Non-Toxic Oxygen absorber, which is a small packet that contains iron powder, salt, and other catalysts. It is designed to absorb oxygen within a sealed package whether it will be manually or vacuum sealed, by creating an oxygen-free environment and by minimizing the presence of oxygen, it helps prevent food spoilage, oxidation, and the growth of microorganisms, and ultimately extending the shelf life of packaged food items.
https://www.oxygen-absorbers.com