1. Department of Consumer and Food Sciences, Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Pretoria 0028, South Africa
2. Department of Hygiene and Public Health, Veterinary Faculty, Eduardo Mondlane University, Maputo P.O. Box 257, Mozambique
3. National Food Institute, Technical University of Denmark, Private Bag 201, 2800 Kongens Lyngby, Denmark