Characterization of the Major Odorants in Non-Alcoholic Beers Brewed with Either Kluyveromyces marxianus or Cyberlindnera saturnus

Consumer behavior is increasingly shifting toward non-alcoholic beers. However, dealcoholized beers often have a reduced aroma compared to their alcoholic counterparts. An alternative for producing non-alcoholic beers is the use of special yeasts with reduced sugar metabolization; however, there are still significant gaps in our knowledge regarding the molecular contribution of non-Saccharomyces yeasts to beer aroma. Applying a comparative aroma extract dilution analysis to two non-alcoholic beers brewed with Kluyveromyces marxianus or Cyberlindnera saturnus resulted in 31 odor-active compounds, among which 27 were detected in both beer samples. Sensory evaluation showed well-balanced aromas in the two beers, with a more intense banana note in the beer brewed with C. saturnus. Among the 22 odorants that exceeded their odor threshold concentrations in the C. saturnus beer was the banana-like smelling 3-methylbutyl acetate, which showed a significantly lower odor activity value in the K. marxianus beer (OAVs 830 vs. 8.2). Its decisive role in the banana note of the C. saturnus beer was finally confirmed in a spiking experiment.