Name (also called flor yeast) for special yeasts of the species Saccharomyces bayanus, capensis, cheriensis, fermentati, montuliensis and rouxii. These are capable of converting sugar into alcohol in the first anaerobic phase (without oxygen) of fermentation. Afterwards the pile yeasts can switch the metabolism to aerobic (with oxygen), so that a waxy, initially white coating is formed from alcohol and oxygen, which coats the individual yeast cells. As a result, the yeast cells rise to the surface of the wine and form a centimetre-thick layer (film), which increasingly turns brown. This protects the wine from...