1. National Center for Agricultural Utilization Research, Biomaterials Processing Research and Bioactive Agents Research, respectively, ARS, USDA, MWA, 1815 N. University, Peoria, IL 61604. Mention of trademark or proprietary products does not constitute a guarantee or warranty by the U.S. Department of Agriculture and does not imply its approval to the exclusion of other products that may also be suitable.
2. Corresponding author. Phone: 309/685-4011. Fax: 309/681-6686.