fermentation in bottle, plays an important part in sparkling winemaking. In most still wines, however, it is one of the wine faults most feared by winemakers. It usually results from the presence of some residual sugar together with live cells of either yeast or bacteria under conditions which favour their growth. (High alcoholic strength and high levels of sulfur dioxide inhibit the growth of such micro-organisms.) It is also possible that a completely dry wine will appear to start fermenting in bottle if it contains a high concentration of malic acid since live lactic acid bacteria may metabolize the malic acid causing a malolactic conversion in bottle.