Improved Corn Ethanol Fermentation and Oil Distribution by Using Polysaccharide Hydrolyzing Enzymes

Abstract

We determined the effects of a commercial proprietary formulation of polysaccharide hydrolyzing enzymes on ethanol fermentation performance, oil partitioning and recovery, and quality of dried distillers grains with solubles (DDGS) on a 1.5-L and 50-L fermentation scale. The enzyme was added at the start of fermentation. Whole beer was subjected to beer well incubation, distillation, and separation of thin stillage from the wet cake. The enzyme promoted faster ethanol production without affecting the final ethanol yield. The enzyme treatments resulted in 8–18% higher wet yield of thin stillage than the control, 13–21% of oil increase in thin stillage, and 11% fiber reduction in DDGS. Free oil recovery from thin stillage was improved by the enzyme treatments (13–53% increase). The present study shows that the use of the polysaccharide hydrolyzing enzymes can add benefits to ethanol plants by increasing corn oil yield and producing fermentation coproducts with increased nutritional value and potentially broader applications in animal feeds