Project puts Finnish touch to packaging coating based on tree bark
Suberin, a natural compound found in birch bark, could act as a moisture barrier in food packaging.
Scientists at the University of Oulu, Finland, believe the resulting coating could be applied to fibre-based packaging materials as a water vapour barrier.
After the moist suberin material is extracted from birch outer bark, the team explains how the natural compound is dried and further processed into a fine powder, which is then mixed into a uniform coating formulation.
Suberin particles are evenly distributed into the water-based coating and additional components are included so the coating can spread evenly and achieve the desired functional properties.
The team applied its coating to two different wood fibre-based paper substrates – UPM and Metsä Board – and undertook multiple trial runs, resulting in a total coated length of around 1,200-1,500m.
