1. Department of Food Science and Human Nutrition, Michigan State University, East Lansing, MI 48824, U.S.A.
2. Current address: Department of Food and Bioproduct Sciences, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8, Canada.
3. Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI 48824, U.S.A.