From Yeast to Glass

Experts from microbiology, the brewing industry, and regional development met last week at Eurac Research to scientifically explore beer. The central question was how to produce non-alcoholic beers in such a way that their aroma profile and taste differ as little as possible from those of traditional full-strength beers.

Yeast plays a key role in this process: it converts sugar into alcohol and carbon dioxide, while also shaping the aromas of a beer. Unlike grapes in wine production, grains such as wheat do not naturally carry suitable yeasts for fermentation. In brewing, yeast is therefore deliberately added and is decisive for the beer’s character. It is not without reason that brewers say: the brewer makes the wort, the yeast makes the beer.

New impulses are coming from local yeasts from South Tyrol. In recent months, researchers have isolated such strains—from old brewing kettles and utensils, from tree bark, and from soils around abandoned breweries. What seems innovative today was once common practice: breweries sourced their yeasts from the surrounding environment and maintained them over generations, much like a sourdough culture.

Today, however, these highly diverse mixed cultures of top- and bottom-fermenting yeasts have largely been replaced by standardized pure cultures from laboratories. Although this issue has so far received little attention in beer production, a look at France—for example, in Camembert production—suggests a potential risk: highly domesticated cultures may lose their ability to reproduce over time. This makes alternatives all the more important — such as the rediscovered mixed yeasts.

The return to local yeasts opens up new possibilities: for flavor, for safeguarding genetic diversity, and for regional economic cycles. If raw materials for beer production—grains, hops, and yeast—are increasingly produced locally again, new perspectives emerge for both agriculture and breweries.

A Beer Craft Forum also cannot ignore the fastest-growing market trend in the industry: non-alcoholic beer. Its production is considered challenging because alcohol and aroma normally develop together during fermentation. In addition to technical and thermal processes, so-called maltose-negative yeasts could play a key role. However, it is likely that a combination of several approaches will be needed to produce non-alcoholic beers that are almost indistinguishable from their alcoholic counterparts in sensory terms.

That these developments are not merely theoretical was evident at the forum itself: only non-alcoholic beers were tasted. The remarkable diversity and quality (including beers with South Tyrolean involvement from the “yeast hunt”) demonstrate how significant this market segment has already become.

And perhaps this very exchange has already sparked the next idea for a new beer creation in some of the participants.