1. University of Aarhus, Faculty of Agricultural Sciences, Department of Food Science, P.O. Box 50, DK-8830 Tjele, Denmark; Interdisciplinary Nanoscience Center (iNANO), University of Aarhus, Faculty of Natural Science, Building 1521, Ny Munkegade, DK-8000 Århus C, Denmark; Arla Foods amba, Skanderborgvej 277, DK-8260, Viby J, Denmark; and German Aerospace Center (DLR), Institute of Materials Physics in Space, Linder Hoehe, 51147 Köln, Germany