1. 1Johnsonville Sausage, L.L.C., N6927 Johnsonville Way, Sheboygan Falls, Wisconsin 53085
2. 2Department of Animal Science, 215 Meat Laboratory, Iowa State University, Ames, Iowa 50011, USA
3. 3Department of Food Science and Human Nutrition, 2312 Food Science Building, Iowa State University, Ames, Iowa 50011, USA
4. 4Department of Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, Iowa 50011, USA