1. Food Materials Science Division, Institute of Food Research, Norwich Research Park, Colney, Norwich NR4 7UA, United Kingdom
2. Current address: Unilever Research, Colworth Laboratory, Colworth House, Bedford MK44 1LQ, United Kingdom
3. Current address: Hellenic Sugar Industry, Sindos, Thessalonika, Greece
4. Department of Agriculture, University of Reading, Earley Gate, P.O. Box 236, Reading RG6 6AT, United Kingdom