Probiotic Yeast for Brewing? A Mini-Review of Craft Brewing Research with Saccharomyces cerevisiae var. boulardii

The brewing industry remains at the forefront of technological innovation, with growing interest in alternative yeasts. Saccharomyces cerevisiae var. boulardii, a well-established probiotic yeast, has attracted attention for its potential to produce probiotic-enriched beers, offering an option for moderate consumers seeking functional beverages. This mini-review brings together current research on the use of S. boulardii in craft brewing, focusing on fermentation performance, flavour and sensory characteristics, and potential health-related functions. While often regarded as a variant of S. cerevisiae, S. boulardii shows comparable or greater cell growth, increased acetic acid production at the expense of glycerol, and lower alcohol yield compared to S. cerevisiae. Despite these differences, beers brewed with S. boulardii exhibit similar volatile compound profiles and sensory characteristics to those produced with S. cerevisiae. In terms of health-related attributes, S. boulardii-fermented beers show higher antioxidant activity, the presence of malto-oligosaccharides with prebiotic potential, and the ability of yeast to survive both storage and gastrointestinal transit. Strategies explored to optimise its brewing performance and customer acceptance include co-fermentation with S. cerevisiae, modified mashing protocols, and natural flavour additions. Overall, the available evidence supports S. boulardii as a promising yeast for developing probiotic-enriched beers. Further research is needed to validate current findings at commercial scales, investigate host–microbiome interactions following beer consumption and develop strategies that balance probiotic efficacy and desirable beer appearance over shelf life. The paper may assist brewers in making informed decisions about deploying S. boulardii, aligning consumer interest in functional beverages with the enjoyment of beer.