Yeasts play a very important role in brewing. In addition to being responsible for carrying out fermentation, generating mainly ethanol and carbon dioxide, they are also able to metabolize and produce a large number of organic compounds that have a decisive impact on the final flavor of beer. Saccharomyces cerevisiae and Saccharomyces pastorianus species are traditionally used in the production of ale and lager beers, respectively. However, the continuous growth of the craft beer market and the increasing interest and demands of consumers have oriented efforts towards the production of differential and innovative beers. In this point, non-conventional yeasts have acquired a relevant role as a tool for the development of new products. In the present work, we describe the potential application in the brewing sector of different non-conventional yeast species belonging to the genus Brettanomyces, Torulaspora, Lachancea, Hanseniaspora, Pichia y Mrakia, among others; as well as yeasts of the genus Saccharomyces, but different from traditional brewing yeasts. The fermentation conditions of these non-conventional yeast are reviewed, along with their abilities to assimilate and metabolize various components of the wort and to provide differential characteristics to the final product. Knowing the state of the art of non-conventional yeasts is essential to evaluate its application in the production of novel craft beers with different characteristics, such as flavored beers, non-alcoholic beers, low-calorie beers and functional beers.
Non-conventional yeasts as tools for innovation and differentiation in brewing
