Unlocking Non-Saccharomyces Metabolic Diversity for the Production of Low- and Reduced-Alcohol Wine and Beer

The global beverage market is experiencing a growing demand for low- and reduced-alcohol wines and beers, driven by shifting consumer preferences toward healthier lifestyles and stricter regulations. While conventional physical dealcoholization methods often compromise the sensory profile and texture of the final product, biological approaches using non-Saccharomyces yeasts have emerged as a sustainable and innovative alternative. This review provides a comprehensive overview of the metabolic diversity of the main non-Saccharomyces genera, assessing their potential for ethanol reduction in both grape juice and wort. We compare the different carbon transport and diversion strategies employed by these yeasts across distinct matrices, from the redirection of hexoses toward glycerol or lactic acid pathways in winemaking to the utilization of maltose-negative phenotypes that naturally limit attenuation in brewing. Furthermore, this review addresses the crucial role of non-Saccharomyces metabolism in sensory compensation, detailing how specific enzymatic activities and the production of volatile compounds (esters, higher alcohols) counteract the loss of mouthfeel and aroma volatility typically associated with ethanol reduction. Finally, critical technological bottlenecks, such as controlled aeration strategies, the nutritional impact of micro-oxygenation and subsequent nutrient competition (primarily nitrogen) between non-Saccharomyces and Saccharomyces yeasts in co-inoculations, and microbiological stability under low-alcohol conditions, are discussed. By providing a direct comparative analysis between wine and beer applications, this review highlights how exploiting biodiversity can reshape the technological landscape of low-alcohol beverage production.