What does the term "high fermentation" refer to in Belgian brewing?

The term "high fermentation" in Belgian brewing primarily refers to the temperature and rustic yeast strains used during the fermentation process. Belgian beers, particularly those labeled as "Belgian-style," often employ warm fermentation techniques that allow yeast to thrive in a higher temperature range compared to many other styles. This process encourages the development of distinct flavors and aromatic compounds unique to Belgian ales.

The yeast strains commonly used in these brews are typically more robust and can produce esters and phenols at higher fermentation temperatures, contributing to the characteristic fruity and spicy notes found in many Belgian beers. This approach contrasts with "low fermentation" styles, such as lagers, which ferment at cooler temperatures with different yeast strains to produce a cleaner profile.

While higher alcohol content could be a result of fermentation, it is not what defines the term "high fermentation." Similarly, high-pressure fermentation vessels are not specific to Belgian brewing and are used in various styles. Dark beers represent a color characteristic rather than fermentation technique. Therefore, understanding the context of yeast behavior in conjunction with temperature during fermentation clarifies why option B accurately captures the essence of "high fermentation" in this brewing tradition.