| Summary: | Over the past 20 years, a number of non-Saccharomyces strains have entered the market, promising various benefits for winemaking. Some strains have been reported to increase the aromatic diversity in wine. In the present study, the non-commercially available strain Starmerella lactis-condensi was tested for this purpose in the production of dry Grüner Veltliner wines. Two experiments were conducted. In the large-scale experiment, 200 L batches of pasteurised Grüner Veltliner must were fermented with St. lactis-condensi, Saccharomyces cerevisiae or both St. lactis-condensi and S. cerevisiae co-inoculation, with three replicates per vintage and variants over two vintages. The wines were characterised analytically, focusing on fermentation and primary aromas, and submitted to sensory analysis. In the small-scale experiment, 34 L of unpasteurised Grüner Veltliner must was compared with unpasteurised Pinot blanc must, using the same fermentation strategy as in the large-scale experiment. These wines were characterised with a focus on fermentation aromas. The results showed that St. lactis-condensi was able to ferment the musts dry, but the finished wines had a lower concentration in thiols, rotundone, some esters and monoterpens and in terms of organoleptic properties, received fewer mentions for aroma descriptors. In comparison, the unpasteurised must fermented with St. lactis-condensi also showed lower concentrations of some free monoterpenes and minor esters but in general, fewer compounds were significantly affected. In contrast to the other aroma groups, it is noteworthy that the mixed varieties showed the highest concentrations of major ethyl esters in both pasteurised and unpasteurised fermentations. Since thiols, rotundone and minor esters are crucial for the aroma profile of Grüner Veltliner wines, the hypothesis that the non-commercial yeast St. lactis-condensi has an advantage over S. cerevisiae in producing particularly aromatic dry white wines can be rejected. Further research is recommended, especially regarding the influence of yeast selection on the rotundone content of Grüner Veltliner, which has been documented for the first time in this study.
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