Yeast In Winemaking – How Important Is It
Yeast in winemaking – Well some would say wine yeast is the most important ingredient as it converts the sugar and fruit juice (or whatever juice you may use) into alcohol, with carbon dioxide in abundance the yeast converts the juice and sugar into alcohol. When fermentation is taking place in a demijohn with an airlock fitted there is no oxygen present.
The type of yeast you use greatly affects the flavour of the wine, so experimenting with different types of yeast is a must (sorry about the pun). See also Yeast nutrient