Wine yeast. Coloured scanning electron micrograph (SEM) of groups of wine yeast cells, Saccharomyces ellipsoideus (or Saccharomyces cerevisiae var. ellipsoideus). Wine yeast is usually considered a variety of baker's or brewer's yeast. The cells consist typically of single vegetative cells which bud off smaller daughter" cells. Wine yeast is used in the fermentation of wine and sherry. This yeast takes over the fermentation process when the wild yeasts (notably S. apiculatus) which start off the fermentation die when the wine is fortified with wine spirit. Wine yeast completes the process of fermentation. Magnification: x800 at 6x7cm size."