Yeasts and their importance to the flavour of traditional Chinese liquor: a review

As one of the three major distilled spirits in the world, traditional Chinese liquor has a distinctive aroma and taste. The brewing process typically involves two stages: the Daqu-making process and the liquor-making process. Further, it commonly adopts solid state fermentation in an open environment, which involves diverse microorganisms such as bacteria and fungi. Yeasts, as an integral brewing microorganism, are not only a dominant force in the fermentation process but also play a key role in the quality and character of different flavour liquors. Studies on yeasts associated with Chinese liquor have rarely compared them with those associated with other alcoholic beverages (wine, sake, etc.), especially in the microbiome-related flavour of the alcoholic beverage. Here, we review the Chinese liquor brewing process, the yeast community in the brewing process, the yeast derived flavour compounds, the interaction between yeasts and other microorganisms and gene level modifications.