As brewers have explored the use of new engineered yeast strains to promote thiol release in various beer styles, it has become clear that the most thiol-driven recipes are blonde ales, pale ales, and lagers. This is both due to barley malt being an abundant source of thiol precursor and the complex nature of thiol sensory. This session will evaluate the impact of thiols in finished beers with an interactive sensory demonstration of a primarily malt-focused beer and a dry-hopped beer fermented with thiol-releasing yeast. First, a brief introduction to thiol sensory will be performed, comparing two beers fermented with and without thiol-releasing yeast. A very clear observation is that thiols produced from malt do not replace “hop character” and instead have an intense tropical aroma similar to that found in passion fruit, guava, and in wines with characteristically high thiol levels. Second, a non-dry-hopped and dry-hopped sample fermented with thiol-releasing yeast will be compared. Though the two finished beer samples have comparable thiol levels, the complexity of hop aroma lowers the perceived thiol intensity. In addition to these sensory demonstrations, we’ll overview our current research on malt types and hopping methods to manipulate thiol sensory in beer recipes. Overall, brewers will leave with a fun sensory training in thiols and a crash course in the complex dynamics between hops and thiol-releasing yeast strains.

Learning Objectives:

• Attend a sensory training in identifying thiol compounds in beer Learn how malt choice and hopping rates can be used to adjust thiol intensity in beers fermented with thiol-releasing yeast Understand the interactions between thiols produced by yeast in fermentation and hop aroma