Institution: | a Nestlé Research Centre, Vers-Chez-Les-Blanc, 1000 Lausanne 26, Switzerland;b Department of Microbiology, University of Groningen, Kerklaan 30, NL-9751 NN Haren, Netherlands;c Nestlé Product Technology Centre, Nestlé-Strasse-3, 3510 Konolfingen, Switzerland |