Oxygen absorbers for food

Iron powders that extend shelf life and maintain quality   

Iron powders are the backbone of modern oxygen absorbers for food. They chemically bind iron oxides, are used in sachets, patches and films for food packaging, and their performance depends strongly on the iron powder’s properties.

There are multiple types of oxygen absorbers. The oxygen absorbers using iron powder are effective and popular in the food packaging industry today. The performance relies strongly on particle morphology, porosity, particle size, apparent density and chemical purity.

Key iron powder properties for oxygen absorbers

Particle morphology and porosity is vital as irregular or sponge-like particles with high internal surface area provide more active surface for oxidation and better contact with catalysts and activators.

Another important property is particle size. Finer powders have higher surface area and faster kinetics, but too fine powders may present handling and containment challenges inside sachets. Hence, the particle size must be tailored for desired uptake rate and handling. 

Apparent density affects sachet filling, permeability and how much active metal fits in each packet volume. Höganäs has a wide range of iron powder grades with controlled particle size and morphology.

Chemical purity is also important for some food applications when you might want to avoid unwanted contaminants and to meet regulatory requirements.

Longer shelf life, safer packaging and consistent performance

Höganäs recommends sponge iron powder for use in oxygen absorbers for food. Sponge iron powder is the most ideal product because of its excellent porosity, which reacts with moisture, removes oxygen and preserves food. Simply put, the bigger the porosity, the better for this kind of application.

Benefits with iron-based oxygen absorbers typically include improved shelf life, reduced oxidation of lipids/oleoresins, retained flavour and colour, and lower need for chemical preservatives if used correctly.

Höganäs produces a wide range of iron powders with tight batch control and the material characteristics needed by oxygen absorber formulators. If you are developing oxygen absorbers for food applications, Höganäs is your trusted and logical metal-powder source. Höganäs’ iron powders give predictable kinetics, high surface area and traceability.