Which ingredient is typically used in the fermentation of a Berliner Weiss?

In the fermentation of a Berliner Weiss, both brewers yeast and Lactobacillus are essential ingredients. Berliner Weiss is a traditional German sour wheat beer characterized by its tartness and refreshing qualities.

Lactobacillus is a crucial component because it is responsible for the lactic acid fermentation that gives this style its distinctive sour flavor. This bacterium works by converting sugars into lactic acid, producing the signature tartness associated with Berliner Weiss.

Brewer's yeast, often Saccharomyces cerevisiae, is also used in the fermentation process to convert the remaining sugars into alcohol and carbon dioxide, completing the typical fermentation profile. The combination of these two organisms results in a balanced beer with both sour and alcoholic characteristics.

Although each organism can play a separate role in different beer styles, Berliner Weiss relies on the synergy between both Lactobacillus and brewer's yeast to achieve its typical flavor, aroma, and mouthfeel. This integration highlights the unique fermentation process used in crafting this refreshing and complex beer style.