
John K. answered 06/01/19
Personal Tutor for Organic Chemistry and General Chemistry
Ethanol is the product of fermentation of carbohydrates such as sugars. To the extend that sugars are available to be fermented by the appropriate enzymes, ethanol can be produced. Sometimes sugars are not immediately available, and must be formed by conversion, in the presence of acid, of starch; this is the case with corn, where the abundant starch is converted to sugars, and then fermentation of the sugars results in alcohol.