Which of the following is primarily a yeast-derived flavor?

Banana is primarily a yeast-derived flavor, specifically associated with certain strains of yeast used in brewing, such as Saccharomyces cerevisiae. This yeast produces esters and phenols during fermentation, which contribute to distinct flavors and aromas in the beer. In the case of banana flavor, it primarily comes from the ester known as isoamyl acetate, which is characterized by its banana-like aroma.

This flavor is particularly prominent in specific styles of beer, such as Hefeweizens and other wheat beers where these yeast strains are commonly used. Understanding this helps brewers choose yeast strains that will produce desired flavor profiles in their beers.

In contrast, the other options—biscuit, citrus, and minty flavors—are typically derived from malt characteristics, hop varieties, or adjuncts rather than from yeast. Biscuit flavors often come from the malt used in the brewing process, while citrus notes are usually associated with hops, and minty flavors could come from particular herbs used in brewing. Thus, banana stands out as a distinctive flavor that is directly linked to yeast activity during fermentation.