Which flavor is not a product of fermentation in beer?

Fermentation is the process by which yeast converts sugars into alcohol and carbon dioxide, resulting in various flavors and aromas in beer. Among the flavors produced during fermentation, alcohol, fruitiness, and even some bitterness can emerge from the interaction of yeast with the ingredients.

Alcohol is a direct product of fermentation, as yeast consumes the sugars from malted grains and transforms them into alcohol. Similarly, fruitiness can arise from the specific strains of yeast used or from the addition of fruit during the fermentation process, producing esters and phenols that contribute fruity characteristics to the beer. Bitterness primarily comes from hops, which impart their bittering qualities to beer, but there can be some interaction with yeast during fermentation that also contributes to the perception of bitterness.

On the other hand, caramel flavor typically results from the caramelization of sugars during the malt roasting process before fermentation occurs. While caramel flavors can enhance a beer's complexity, they are not directly produced by fermentation itself; instead, they originate from the malting process. Therefore, caramel is the flavor that is not a product of fermentation in beer.