Research Supplement
The polysaccharides of New Zealand Pinot noir wines: the influence of yeasts on their content and profile Hayden Jones-Moore, Dr Rebecca Jelley and Associate Professor Bruno Fedrizzi THE ROLE OF YEASTS is complex and strongly associated with wine quality: the selection of yeasts can modify and improve the technological and sensory properties of wine. Yeasts have the ability to improve wine colour by the metabolic formation of stable colour pigments, enhance aroma by the production of volatile compounds, and enrich wine with polysaccharides, which facilitate colloidal stability to
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improve clarity, stability and enhance the ‘body’ of the wine. Overall, it is important for winemakers to have an understanding of how yeast can influence key parameters of wine, in order to assist with the creation of particular styles of wine or even improve quality, elaborating their selection and range. Wine polysaccharides are large,
NZ WINEGROWER DECEMBER 2021/JANUARY 2022
complex chains of simple sugars. The cell walls of both grape and yeast tissue contain polysaccharides which are introduced into wine during maceration, fermentation and ageing processes. Polysaccharides have previously been reported to exist in wine at concentrations between 0–2 g L-1, however, this is highly dependent on the variety, vintage, climate, processing techniques and