1. Laboratory of Food Chemistry, Katholieke Universiteit Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium.
2. Corresponding author. Phone: (+32)-16-321582. Fax: (+32)-16-321997. E-mail: Lieve.Lamberts@biw.kuleuven.be
3. Masterfoods, Industrielaan 5, B-2250 Olen, Belgium.