1. 1Food Hygiene and Microbiology Group, Department of Agrotechnology and Food Sciences, Wageningen University and Research Center, P.O. Box 8129, 6700 EV Wageningen, The Netherlands
2. 2Consumer Technology and Product Use Group, Department of Agrotechnology and Food Sciences, Wageningen University and Research Center, P.O. Box 8129, 6700 EV Wageningen, The Netherlands
3. 3Quality and Safety Assurance, Nestlé Research Center, P.O. Box 44, CH 1000 Lausanne 26, Switzerland