1. Institute of Nutritional Physiology, Federal Research Centre for Nutrition and Food, Haid-und-Neu-Str. 9, 76131 Karlsruhe, Germany, Department of Food and Nutrition, Technical University of Munich, 85354 Freising-Weihenstephan, Germany, and Department of Wine Analysis and Beverage Research, Geisenheim Research Center, 65366 Geisenheim, Germany