What kind of esters does Kloekera produce during the first stage of lambic fermentation?

Kloekera, a type of yeast commonly found in the lambic fermentation process, is known for producing volatile esters during the initial phase of fermentation. These esters are typically responsible for the fruity and aromatic qualities found in lambics, contributing to their overall complexity.

During fermentation, as the primary yeast activity occurs, these volatile esters may initially be abundant but can evaporate or be reabsorbed by the yeast and other microbial activity, leading to a reduction in their concentration as fermentation progresses. This characteristic is significant because it means that while these esters contribute to the profile of the fermentation, they do not remain stable throughout the entire brewing process.

In contrast, stable esters are usually produced at later stages of fermentation and are more long-lasting, enhancing the final aroma and flavor of the beer. Sweet esters, while they can enhance flavor, are not specifically associated with Kloekera in the initial stages of lambic fermentation, and fermented esters typically do not contribute bitterness. Understanding the nature of these esters is crucial for appreciating the complex flavor profile of lambics and the roles different microorganisms play in their production.