Working in collaboration with the Technische Universität München (TUM), Fraunhofer Institute for Process Engineering and Packaging IVV has developed a multilayer packaging film containing a new fully biodegradable, plant-derived oxygen scavenger: gallic acid.
Fraunhofer IVV is now looking for partners to take the next step towards market implementation.
Gallic acid occurs naturally in plants. In combination with a base, gallic acid is a potent oxygen scavenger with a very high oxygen absorption capacity. One gram of gallic acid absorbs 450 mg of oxygen – more than the capacity of the iron powder that is currently used.
The absorption reaction is activated by the humidity of the food. A multilayer packaging film was produced in a pilot-scale three-step process involving compounding, cast film extrusion, and lamination. The film comprised a food contact layer (Bio PE), an active layer containing the scavenger (Bio PE + 15% (w/w) OSc), a biobased adhesive, and an outer barrier layer (PLA) that reduced O2 ingress from the environment.
The film could be thermoformed to produce trays suitable for thermo-sealing. Interestingly, gallic acid was found to be able to withstand the extrusion process. The film reacts with oxygen at a relative humidity > 75 % and is therefore suitable for food products with a high-water activity, which need to be protected from headspace oxygen or oxygen permeation. By using gallic acid, active packaging materials fully made of sustainable materials can be achieved.
The results of the study can be found here: