Cicerone Certified Beer Server Practice Exam

Which ingredient in beer is responsible for fermentation?

1. Hops

2. Water

3. Yeast

4. Malt

The correct answer is: Yeast

The ingredient responsible for fermentation in beer is yeast. Fermentation is a crucial process in beer production where yeast converts sugars into alcohol and carbon dioxide. This transformation takes place after the wort—composed primarily of sugars from malt—has been created. The yeast consumes these sugars and produces ethanol, which is the alcohol found in beer, along with carbon dioxide, which contributes to the beer's fizziness. Hops, while important for bitterness and aroma, do not play a role in fermentation. They are added primarily for flavor and preservative qualities. Water serves as a primary component of beer, affecting the overall mouthfeel and flavor but not fermentation directly. Malt provides the sugars necessary for fermentation but does not ferment; it is the yeast that takes those sugars and converts them into alcohol. Thus, understanding the integral role of yeast gives clear insight into its significance in the brewing process.