1. Matforsk AS, Norwegian Food Research Institute, Osloveien 1, N-1430 Aas, Norway, Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, N-1432 Aas, Norway, and Department of Food Science and Technology, Oregon State University, 100 Wiegand Hall, Corvallis, Oregon 97331-6602