Studies on the Genetic Characteristics of the Brewing Yeasts Saccharomyces: A Review

Brewing yeasts have an essential role in beer production as they convert sugar into ethanol and carbon dioxide and impart flavor to beer during brewing. Brewing yeasts can be classified into the following two types: ale yeast (or top-fermenting yeast; Saccharomyces cerevisiae), which is used for ale-type beer production; lager yeast (or bottom-fermenting yeast; Saccharomyces pastorianus), which is used for lager-type beer production. Globally, approximately 90% of beer is produced using lager yeast. The entire genomes of S. cerevisiae S288C and S. pastorianus Weihenstephan 34/70 were sequenced in 1996 and 2009, respectively. Saccharomyces eubayanus, a parent strain of the lager yeast, was discovered in 2011. These advances have markedly contributed to the studies on brewing characteristics and brewing yeast genes and the rapid development of the field of yeast genetics. To contribute to the development of the beer industry, this review summarizes the genetics of brewer’s yeast with a special focus on its genomic structure and the genes involved in brewing characteristics.