• Antimicrobial surface coatings: The use of preservatives can be minimized by depositing biocidal agents at the interface between the food and packaging. Approved preservatives such as benzoic acid and sorbic acid, and also other microbiological agents, are applied to the film by lacquering, laminating, or coextrusion and diffuse to the surface of the food. There are potential appli¬cations here for paste-like and solid foods whose surfaces come into direct contact with the film. A film containing sorbic acid has been specially developed for this purpose at Fraunhofer IVV. In addition we hold a patent for manufac¬turing antimicrobial coatings.
• Humidity regulating materials:These materials set the relative humidity inside packaging.
* Selection and modification of poly- mers and humidity regulating agents
* Combination with microperforations and macroperforations
* Incorporation of active substances into the polymer matrixScientists at Fraunhofer IVV have developed a polymer film containing added salt.
• Moisture absorbing materials:Desiccants are being incorporated into polymers in order to protect food products and pharmaceuticals against moisture uptake. One such approach being used by Fraunhofer IVV involves using calcium oxide in packaging materials.
• Ethylene absorbers:By absorbing ethylene, which is responsible for the ripening and spoiling of agricultural produce such as fruit and vegetables, natural food products can be kept fresh until they are consumed. Fraunhofer IVV scientists have developed corrugated board that absorbs ethylene.