Not your ordinary yeast: non-Saccharomyces yeasts in wine production uncovered.

摘要

Saccharomyces cerevisiae and grape juice are "natural companions" and make a happy wine marriage. However, this relationship can be enriched by allowing "wild" non-Saccharomyces yeast to participate in a sequential manner in the early phases of grape must fermentation. However, such a triangular relationship is complex and can only be taken to "the next level" if there are no spoilage yeast present and if the "wine yeast" - S. cerevisiae - is able to exert its dominance in time to successfully complete the alcoholic fermentation. Winemakers apply various "matchmaking" strategies (e.g. cellar hygiene, pH, SO₂, temperature and nutrient management) to keep "spoilers" (e.g. Dekkera bruxellensis) at bay, and allow "compatible" wild yeast (e.g. Torulaspora delbrueckii, Pichia kluyveri, Lachancea thermotolerans and Candida/Metschnikowia pulcherrima) to harmonize with potent S. cerevisiae wine yeast and bring the best out in wine. Mismatching can lead to a "two is company, three is a crowd" scenario. More than 40 of the 1500 known yeast species have been isolated from grape must. In this article, we review the specific flavour-active characteristics of those non-Saccharomyces species that might play a positive role in both spontaneous and inoculated wine ferments. We seek to present "single-species" and "multi-species" ferments in a new light and a new context, and we raise important questions about the direction of mixed-fermentation research to address market trends regarding so-called "natural" wines. This review also highlights that, despite the fact that most frontier research and technological developments are often focussed primarily on S. cerevisiae, non-Saccharomyces research can benefit from the techniques and knowledge developed by research on the former