1. Department of Food Science and Nutrition, University of Minnesota, 1334 Eckles Avenue, St. Paul, Minnesota 55108, United States
2. Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
3. Raman Spectroscopy Group, Thermo Fisher Scientific, 5225 Verona Road, Building 4, Madison, Wisconsin 53711, United States