Effect of Non-Saccharomyces Yeasts Derived from Traditional Fermented Foods on Beer Fermentation Characteristics and Flavor Profiles

In recent years, numerous studies have demonstrated that non-<i>Saccharomyces</i> yeasts hold potential for industrial application and aroma generation during fermentation. Non-<i>Saccharomyces</i> wild yeasts can be important tools in the development of new products, and the objective of this work was to obtain and characterize novel yeast isolates for their ability to produce beer. Traditional fermented beverages serve as a vital source of yeast strains that can exhibit unique characteristics during the brewing process. Thus, 22 strains of <i>Saccharomycopsis fibuligera</i> were isolated from traditional fermented foods in this work. Subsequently, through primary and secondary screening, <i>S. fibuligera</i> G02 was identified as a promising candidate for beer brewing, attributed to its advantageous physiological traits and notable potential for beer production. Headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS) was employed to analyze the volatile flavor substances in beer fermented using the <i>S. fibuligera</i> G02 strain. Chemometric analysis revealed that <i>S. fibuligera</i> G02 had a unique influence on beer aroma. Accordingly, isoamyl alcohol, phenyl-1-ethanol, ethyl acetate, isoamyl acetate, and 4-ethyl guaiacol (4EG) were the key aroma components of <i>S. fibuligera</i> G02. This work provides useful insights into the non-<i>Saccharomyces</i> yeasts to reference the targeted improvement of beer aroma.