The process of turning grain into ethanol entails cooking, fermentation and distillation.
- Grain is milled, mixed with water and cooked
- Enzymes are added to the mixture to convert starch to sugar
- Yeast is added to start fermentation of the sugars
- Fermented mash is distilled to produce ethanol
The ethanol is treated, or “denatured” with a small volume of gasoline, to turn it into fuel grade ethanol. It is then blended with conventional gasoline at points in the distribution system or at retail outlets.
The grain-to-ethanol process also produces Distillers Dried Grain with Solubles (DDGS), a high protein, non-animal based livestock feed that is sold to cattle and dairy producers. In this way, a portion of the grain feedstock re-enters the food chain.
