Chemistry professor, Katja Heinze, of the Institute of Inorganic Chemistry and Analytical Chemistry of Mainz University has just won the Interregional Research Award with her partner, Dr. Patrick Choquet from the Centre de Recherche Public in Belvaux, Luxembourg, for developing foil packaging that changes colour depending on the freshness of the food within.
The award, worth EUR35,000 (AU$51,000), has been presented for only the sixth time. Its purpose is to encourage collaboration in cross-border research projects and reinforce the profile of interregional research.
The aim of the three year project called SurfAmine was to develop a form of food packaging that would display real-time information on the status of the packaged items. The idea was to create an intelligent foil that would interact with the atmosphere within the package and display information about its composition by changing colour. The project, carried out at the Institute of Inorganic Chemistry and Analytical Chemistry of Johannes Gutenberg University Mainz (JGU), included input from Novelis Foil Innovation Centre and the ArcelorMittal Plasma Research Group in Liège in Belgium.
The teams designed, synthesised, and employed novel dyes that are used to give the foils their colour.
“In view of the series of food scandals that have occurred in recent years, there is an increased interest in monitoring food freshness and in food safety,” Heinze explained.
The work group used chromophores, the part of a molecule responsible for its colour, which react to the volatile amines released during the bacterial degradation by changing colour. These molecules have been incorporated into the sensing layers on the food packaging foils by applying a method known as dielectric barrier discharge. A pigment showing intense colouration, known as metalloporphyrin, was also incorporated into the foils. The group developed tailored metalloporphyrins to increase the porphyrins’ absorption change when they interact with the amines in order to make the change easily visible to the human eye.
In the process, the group developed a new and more environmentally-friendly coating process, with which even large surfaces can be covered with the intelligent materials.
The SurfAmine project is now focussed on the chromophores for third generation solar cells that convert any visible light into electrical energy, known as dye-sensitised solar cells. These light-emitting electrochemical cells are applied for the conversion of light energy for the use in chemical catalysis.
