01
Preparation and conversion
Grain is received, cleaned and milled. Water and enzymes help convert starch into fermentable sugars. Process details vary by plant and feedstock.
02
Fermentation, distillation and dehydration
Yeast converts sugars into ethanol and carbon dioxide. Distillation concentrates the ethanol; dehydration removes the remaining water required to meet fuel specifications.
03
Coproduct recovery
Protein, fibre, fat and other components do not disappear. Plants may recover distillers grains, corn oil, carbon dioxide or other coproducts. Allocation choices around those products matter in lifecycle analysis.