Bacteria

bacteria, very small micro-organisms which have serious implications in both viticulture and winemaking. Although not common pathogens of the grapevine, bacterial diseases are potentially destructive and therefore very important.

In winemaking just two groups of bacteria are important, acetobacter and lactic acid bacteria. Since grape juice and wine are both high in acidity, the great majority of bacteria, with the exception of these two groups, are incapable of living in them and, if introduced, do not survive. (Drinks such as cider, perry, orange juice, and beer are all much less acid than wine, are thereby subject to many forms of bacterial spoilage to which wine is immune, and therefore lack wine’s ageing potential.) No known human pathogenic bacteria can survive in wine, however, which is one of the reasons why it has been such a safe drink (safer than water at some times and in some places) through the ages.