Saccharomyces

Saccharomyces is a genus of yeasts — primarily S. cerevisiae (used in beer, wine, bread, and spirits fermentation) and S. pastorianus (used in lager fermentation) — that convert sugars to ethanol and CO2 through alcoholic fermentation. They are the primary alcohol-generating organisms in all conventional fermented beverages.

Saccharomyces cerevisiae ('sugar-eating' yeast of the 'beer' species, from Latin) has been domesticated by humans for over 10,000 years across bread-making, wine production, and brewing. Its metabolic efficiency, alcohol tolerance (surviving at up to 15–18% ABV), and production of desirable esters and fusel alcohols as fermentation byproducts make it the foundation of global fermented beverage culture. Different strains of S. cerevisiae are selected for different applications — beer strains produce different ester profiles than wine strains, and specific strain-brand combinations are proprietary trade secrets for some producers.

For zero-proof beverage producers, Saccharomyces is both essential and to be managed. In dealcoholized beer and wine production, standard Saccharomyces fermentation produces the full alcoholic beverage that is subsequently dealcoholized. In arrested fermentation and cold contact fermentation, the goal is to limit Saccharomyces activity without completely preventing the flavor development it provides. The strain of Saccharomyces used affects the flavor profile of the base beer before dealcoholization — meaning strain selection remains commercially important even when the ultimate product is NA.

The global Saccharomyces diversity accessible to commercial producers has expanded dramatically through the work of institutions like the National Collection of Yeast Cultures (NCYC, UK) and private collections at major flavor houses. Non-conventional strains — sometimes called 'wildtype' or 'heritage' strains — produce distinctive flavor profiles that differentiate craft producers from those using commodity yeast.

A non-Saccharomyces frontier: non-conventional yeasts including Lachancea thermotolerans (produces significant lactic acid during fermentation, naturally reducing wine pH), Torulaspora delbrueckii (produces complex esters), and Metschnikowia pulcherrima (has strong antimicrobial properties) are being explored for low-alcohol wine production, offering new tools for flavor complexity without requiring conventional dealcoholization.