H2S Production by Different Low-H2S Producing Yeast Strains (2016)

This study examines the effect of different low H2S-producing yeast strains on the sensory attributes of Cabernet Franc and Cabernet Sauvignon Rosé. The grapes were harvested on the same day, pressed together, and after settling was racked into four different 484L puncheons (2006 Hungarian oak from the same cooper). The barrels were inoculated with the following yeasts: Rhône 4600 (ScottLabs), Allegro (Phyterra), Sensy (ScottLabs), and Fermol Elegance (AEB). Rhône 4600 is not marketed as a low H2S-producing yeast strain and was intended to act as a soft control. The strains showed similar fermentation kinetics except for Rhône 4600, which was markedly slower. Additionally, the wine produced by Rhône 4600 had a higher alcohol content and higher total SO2, possibly from yeast production. The sulfide contents of the wines, however, were essentially indistinguishable. No strong trends were found with the descriptors used for this study. Rhône 4600 tended to show higher Fruit Intensity and Overall Aromatic Intensity. Many of these wines were perceived as slightly reduced. In general, people tended to prefer wines produced with Rhône 4600 and Allegro yeasts.

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CY3079 and Vivace Yeast Trial in Chardonnay (2015)

Chardonnay wines produced with CY3079 and Vivace yeast strains were compared. Vivace yeast is marketed as a low hydrogen sulfide-producing yeast.  There were little chemical differences between the resulting wines, although significant sensory differences were discerned.  People tended to prefer the wine produced with CY3079.  No conclusions can be drawn about the efficacy of Vivace in producing low levels of hydrogen sulfide.

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