Ethanol is ethyl alcohol or grain alcohol, mainly produced in the Midwestern United States from corn stock. It can be used as a biofuel alternative to gasoline – known as E85 for its 85 percent ethanol to 15 percent gasoline mixture – in “flex fuel” engines, but it’s primary use in the U.S. is as an oxygenate. As an oxygenate, its mixture is 10 percent or less ethanol in finished gasoline.