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How is Ethanol Made?

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Extended Drought Pushes Corn Prices To Record Highs
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Question: How is Ethanol Made?
Answer: Ethanol can be made from any crop or plant that contains a large amount of sugar or components that can be converted into sugar, such as starch or cellulose.

As their names imply, sugar beets and sugar cane contain natural sugar. Crops such as corn, wheat and barley contain starch that can be easily converted to sugar. Most trees and grasses are made of cellulose, which can also be converted into sugar, although not as easily as starch.

Most ethanol is produced using a four-step process:

  1. The ethanol feedstock (crops or plants) are ground up for easier processing;
  2. Sugar is dissolved from the ground material, or the starch or cellulose is converted into sugar;
  3. Microbes feed on the sugar, producing ethanol and carbon dioxide as byproducts; and
  4. The ethanol is purified to achieve the correct concentration.
It is also possible to produce ethanol through a wet-milling process, which is used by many large ethanol producers. This process also yields byproducts such as high-fructose corn syrup, which is used as a sweetener in many prepared foods.

Ethanol: Frequently Asked Questions

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