1. Appalachian Farming Systems Research Center, Agricultural Research Service, U.S. Department of Agriculture, 1224 Airport Road, Beaver, West Virginia 25813
2. Food Composition and Methods Development Lab, Beltsville Human Nutrition Research Center, Agricultural Research Service, U.S. Department of Agriculture, Building 161, 10300 Baltimore Avenue, BARC-East, Beltsville, Maryland 20705-2350