The death or decline in viable cell numbers will occur generally once the sugars have been depleted from the medium. The death phase is accelerated under conditions of low concentrations of Mg and Ca and under conditions that result in low levels of sterols and fatty acids required for the production of an ethanol-tolerant plasma membrane. Release of small molecules may also occur. The release of hydrolytic enzymes from the vacuole is responsible for the autodigestion, leakiness, and subsequent rupture of the yeast cells, termed autolysis. But this occurs under winemaking