1. Center for Molecular Plant Physiology, Department of Plant Biology, The Royal Veterinary and Agricultural University, 40 Thorsvaldsensvej, DK 1871 Frederiksberg C. Copenhagen, Denmark, Department of Food Science, Swedish University of Agricultural Science, P.O. Box 7051, SE-750 07 Uppsala, Sweden, Regional Laboratory of Physicochemical Analyses and Structural Research, Ingardena 3, 30-060 Cracow, Poland, and Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Cracow, Poland