8.2.2 Fermented beverages

Microbes especially yeast is being used from time immemorial for the production of beverages like wine, beer, whisky, brandy and rum. Wine is among the oldest alcoholic beverages known and is produced by fermentation of fruit juice by yeast. Zymology is an applied science which deals with the biochemical process of fermentation and its practical uses. Saccharomyces cerevisiae commonly called brewer’s yeast is used for fermenting malted cereals and fruit juices to produce various alcoholic beverages.

Wine and beer are produced without distillation, whereas whisky, brandy and rum are obtained by fermentation and distillation. The Pasteur effect is the inhibiting effect of oxygen on the fermentation process. Oenology is the science and study of wine and wine making. Wine is made from the fermentation of grape juice.

Grape juice is fermented by various strains of S accharomyces cerevisiae into alcohol. Grape wine is of two types, red wine and white wine. For red wine, black grapes are used including skins and sometimes the stems also are used. In contrast white wine is produced only from the juice of either white or red grapes without their skin and stems.

Beer is produced from germinated barley malt grain by S accharomyces carlsbergensis or Saccharomyces cerevisiae . Rum is made from fermented sugarcane or molasses or directly from sugarcane juice by S accharomyces cerevisiae . Whisky is a type of distilled alcoholic beverage made from fermented grain mash by Saccharomyces cerevisiae .