Nonconventional yeasts in craft beer brewing

Yeast plays an important role in craft beer production. Indeed, they are responsible for the fermentation process but, above all, they can metabolize and produce many organic compounds that have a decisive impact on the final flavor of beer. In craft beer production, yeast variability may have a more relevant role in the characterization and complexity of flavor. In this regard, nonconventional yeasts may be of great interest due to their wide biodiversity and flavor production. In recent years, the growth of the craft beer market and the growing interest and demands of consumers have directed efforts toward the production of differentiated and innovative beer styles, and for these reasons, nonconventional yeasts have acquired a relevant role in the development of new products. This chapter discusses the use and potential application in the craft beer production sector of different nonconventional yeast species belonging to the genera Torulaspora, Lachancea, Pichia, Hanseniaspora, Schizosaccharomyces, and others will be described. The use of nonconventional yeasts for producing different beers as brew-flavored, nonalcoholic, low-calorie, and functional beers is reported. The main conventional yeast species used in the production of various craft beers are described.