Saccharomyces cerevisiae is the most used yeast species in commercial ethanol production. In that context, what is the primary product of this process?

Saccharomyces cerevisiae is the most used yeast species in commercial ethanol production. In that context, what is the primary product of this process?

• A. Ethanol
• B. Lactic acid
• C. Acetic acid
• D. Glycerol

Answer: (A)

In alcoholic fermentation by Saccharomyces cerevisiae, sugars are converted to pyruvate via glycolysis, and under low oxygen this pyruvate is transformed into acetaldehyde and then ethanol, regenerating NAD+ in the process. This makes ethanol the main product produced in commercial ethanol fermentation. Carbon dioxide is released as a gas, while glycerol is a minor byproduct used for redox balance; lactic acid and acetic acid are not produced as primary products under standard fermentation conditions. Therefore, ethanol is the primary product.

In alcoholic fermentation by Saccharomyces cerevisiae, sugars are converted to pyruvate via glycolysis, and under low oxygen this pyruvate is transformed into acetaldehyde and then ethanol, regenerating NAD+ in the process. This makes ethanol the main product produced in commercial ethanol fermentation. Carbon dioxide is released as a gas, while glycerol is a minor byproduct used for redox balance; lactic acid and acetic acid are not produced as primary products under standard fermentation conditions. Therefore, ethanol is the primary product.