1. Food Science Dept., University of Manitoba, Winnipeg, MB, R3T 2N2, Canada.
2. Present address: Chemsafety Ltd., PO Box 8141, Christchurch, New Zealand.
3. Grain Foods Research Unit, New Zealand Institute for Crop and Food Research Ltd., Private Bag 4704, Christchurch, New Zealand.
4. Corresponding author. E-mail: suttonk@crop.cri.nz