Disclosed is a method for processing cut edges of a blank member, so called “package sleeve”, made from packaging material, in particular paper/plastics composite material, the cut edges of which are open from above and/or below, by applying a processing medium. In order to develop a simple and cost-effective method, in which the risk of contamination of the packaging and the aseptic region of a filling installation when the package sleeves are filled and closed is reduced, the processing medium contains at least one sterilizing medium and the sterilizing medium remains after being applied to the cut edges and is introduced into the packaging material.