1. Department of Food Science, Swedish University of Agricultural Sciences, Box 7051, 750 07 Uppsala, Sweden.
2. Corresponding author. Phone: 46 18 67 20 48. Fax: +46 18 67 29 95. E-mail: Kristine.Koch@lmv.slu.se
3. Department Food Science and Human Nutrition, Iowa State University, Ames, IA 500 11.