1. Department of Analytical and Pharmaceutical Chemistry, Royal Danish School of Pharmacy, Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark, Physical Chemistry 1, and Food Technology, University of Lund, P.O. Box 124, S-22100 Lund, Sweden, Protein Chemistry Laboratory, Department of Molecular Biology, University of Aarhus, The Science Park, Gustavs Wieds Vej 10, DK-8000 Aarhus C, Denmark, and Scotia LipidTeknik AB, P.O. Box 6686, S-113 84 Stockholm, Sweden