What is the definition of fermentation in brewing?

Fermentation in brewing is defined as the transformation of sugars into alcohol and carbon dioxide. This process is primarily carried out by yeast, which consumes the sugars present in wort (the liquid extracted from the malted grains) and produces alcohol and carbon dioxide as byproducts. This essential step not only contributes to the alcohol content of beer but also influences the flavor and aroma profile, as different yeast strains can produce various compounds during fermentation.

Other processes mentioned, such as clarifying beer, breaking down hops, and the heating process of brewing, serve different purposes within brewing but do not encompass the critical transformation that occurs during fermentation. Thus, understanding fermentation is fundamental to the brewing process and the overall development of beer.