In Germany, researchers produced a multilayer bio-based packaging film using gallic acid and sodium carbonate that acts like an oxygen scavenger using a three-step process: compounding, flat film extrusion, and lamination. The new film helps protect oxygen-sensitive food, making it a good solution for food packaging to extend shelf life of those food products.
The researchers investigated the film surface color as well as oxygen absorption at different relative humidities (RHs) and temperatures, and compared the oxygen absorption of OSc powder, monolayer films, and multilayer films. The incorporation of GA into a polymer matrix reduced the rate of oxygen absorption compared to the GA powder because the polymer acted as a barrier to oxygen and water vapor diffusion.
These results demonstrate for the first time the production and the properties of a bio-based multilayer packaging film with GA as the oxygen scavenger. Potential applications include the packaging of food products with high water activity (aw > 0.86).