Adaptive Laboratory Evolution of Ale and Lager Yeasts for Improved Brewing Efficiency and Beer Quality

Yeasts directly impact the efficiency of brewery fermentations as well as the character of the beers produced. In recent years, there has been renewed interest in yeast selection and development inspired by the demand to utilize resources more efficiently and the need to differentiate beers in a competitive market. Reviewed here are the different, non-genetically modified (GM) approaches that have been considered, including bioprospecting, hybridization, and adaptive laboratory evolution (ALE). Particular emphasis is placed on the latter, which represents an extension of the processes that have led to the domestication of strains already used in commercial breweries. ALE can be used to accentuate the positive traits of brewing yeast as well as temper some of the traits that are less desirable from a modern brewer's perspective. This method has the added advantage of being non-GM and therefore suitable for food and beverage production.

Yeast selection for non-alcoholic and low-alcoholic beverages based on wort

A series of wort fermentations with eight yeast strains were carried out in laboratory conditions. The strains used were: Saccharomyces cerevisiae (2 strains), Saccharomyces diastaticus (3 strains), Saccharomyces carlsbergensis (1 strain), Saccharomyces lactis (1 strain), Saccharomyces sake gekkeikan (1 strain). Selection of yeast strains has been performed in order to study the possibilities for their aplication to obtain fermentable non-alcoholic and low-alcoholic beverages based on wort. Three yeast strains (two of Saccharomyces cerevisiae and one Saccharomyces diastaticus), were selected based on their good growth in the used medium and the pleasant organoleptic profile formed as a result of the fermentation carried out. The accumulated alcohol values varied between 0.05 and 0.22 % (w/w).