<P> The role of yeast in winemaking is the most important element that distinguishes wine from grape juice . In the absence of oxygen , yeast converts the sugars of wine grapes into alcohol and carbon dioxide through the process of fermentation . The more sugars in the grapes , the higher the potential alcohol level of the wine if the yeast are allowed to carry out fermentation to dryness . Sometimes winemakers will stop fermentation early in order to leave some residual sugars and sweetness in the wine such as with dessert wines . This can be achieved by dropping fermentation temperatures to the point where the yeast are inactive , sterile filtering the wine to remove the yeast or fortification with brandy to kill off the yeast cells . If fermentation is unintentionally stopped , such as when the yeasts become exhausted of available nutrients , and the wine has not yet reached dryness this is considered a stuck fermentation . </P>
<P> The role of yeast in winemaking is the most important element that distinguishes wine from grape juice . In the absence of oxygen , yeast converts the sugars of wine grapes into alcohol and carbon dioxide through the process of fermentation . The more sugars in the grapes , the higher the potential alcohol level of the wine if the yeast are allowed to carry out fermentation to dryness . Sometimes winemakers will stop fermentation early in order to leave some residual sugars and sweetness in the wine such as with dessert wines . This can be achieved by dropping fermentation temperatures to the point where the yeast are inactive , sterile filtering the wine to remove the yeast or fortification with brandy to kill off the yeast cells . If fermentation is unintentionally stopped , such as when the yeasts become exhausted of available nutrients , and the wine has not yet reached dryness this is considered a stuck fermentation . </P>
the enzyme in whose presence glucose and fructose are converted into alcohol
the enzyme in whose presence glucose and fructose are converted into alcohol
yeast
yeast