Patent 7452425 was granted and assigned to Langhauser Associates Inc on November, 2008 by the United States Patent and Trademark Office.
A grain containing starch, such as corn, is refined. The grain is steeped in water at a temperature of about 125 to 160° F., which water is essentially free of sulfurous acid and contains recycled enzymes from downstream processes, in a counter-current steeping reactor for about 10 to 20 hours to produce an aqueous slurry of steeped grain having a moisture content of about 40 to 50 percent. The various components of the grain are then separated and the starch is converted to ethanol.