Yeasts of the genus Hanseniaspora are bipolar budding yeasts considered non-conventional, yet they are increasingly sought after in the production of fermented beverages. They contribute to a broader aromatic profile and enhance the sensory complexity of the final product. Species within the Hanseniaspora genus are divided into two phylogenetic groups with different evolutionary rates, which also differ in gene count. The fast-evolving lineage (FEL) has a smaller genome and is likely capable of faster growth compared to the slow-evolving lineage (SEL). Therefore, we compared the growth rates of strains from both groups in complex and minimal media. We expected that strains from the FEL group would have a shorter doubling time, confirming our hypothesis that they lost significantly more genes during evolution than strains from the SEL group, which grow more slowly. However, we did not observe significant differences in doubling times between the FEL and SEL groups. We also found that SEL strains possess the gene for the sulfite efflux pump (SSU1). Therefore, we determined the minimum inhibitory concentration (MIC) of potassium metabisulfite for strains from both groups. Interestingly, selected strains, regardless of genetic background, exhibited similar MIC values. Finally, we tested the potential of Hanseniaspora yeasts for beer aroma enhancement. Through screening assays, we evaluated their ability to assimilate maltose and starch, their resistance to ethanol and hop extract, β-lyase activity, and the production of undesirable phenolic compounds. Based on these results, we selected at least one strain from each species that grew well on β-lyase selective media, did not produce volatile phenols, and showed resistance to ethanol and hop extract. These strains demonstrated promising enzymatic potential for beer aroma enhancement, as many did not produce undesirable phenolic compounds. We concluded that certain selected strains are suitable for use in brewing to enhance beer aroma.
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