Strain-Dependent Contributions of Hanseniaspora uvarum Isolate to Apple Cider Fermentation, Chemical Composition and Aroma Complexity

Cider fermentation is strongly influenced by yeast metabolism, which determines both fermentation dynamics and aroma complexity. While Saccharomyces species remain the standard choice, increasing attention has been directed toward non-Saccharomyces yeasts such as Hanseniaspora uvarum, known for their high ester formation and positive impact on sensory attributes. In this study, three native H. uvarum strains were compared with Saccharomyces bayanus in cider production. Fermentation kinetics, physicochemical parameters, and volatile and sensory profiles were assessed. All H. uvarum strains depleted sugars effectively, but strain-specific differences were evident: Kr-4 exhibited the highest ethanol (4.92% v/v) and glycerol (2.88 g/L) production, while Kd-13 showed reduced fermentative vigor. GC–MS analysis revealed higher alcohols as the dominant volatiles, with 3-methyl-1-butanol and phenylethyl alcohol most abundant. The highest concentration of phenylethyl alcohol was found in cider fermented with H. uvarum Kd-13. Ester diversity was also strain-dependent, with H. uvarum Kd-13 producing increased levels of monoethyl succinate and ethyl phenylacetate. Sensory evaluation identified ciders produced with H. uvarum Kd-13 and Kr-4 as the most complex, whereas the control sample was perceived to have a lighter body and intensive acidity. These findings highlight significant strain-level variability within H. uvarum, underlining its potential for tailoring cider aroma and sensory quality.