Alcohol fermentation is done by yeast and some kinds of bacteria. These microorganisms convert sugars in ethyl alcohol and carbon dioxide. Alcoholic fermentation begins after
glucose enters the cell. The glucose is broken down into pyruvic acid. This pyruvic acid is then converted to CO2, ethanol, and energy for the cell. Humans have long taken advantage of this process in making bread, beer, and wine. In these three product the same microorganism is used: the common yeast or Saccharomyces Cerevisae
During the fermentation process of bread, sugar is converted into alcohol and carbon dioxide. The carbon dioxide will form bubbles, which will be trapped by the gluten of the wheat causing the bread to rise. Because the bread fermentation takes a short period, only small amounts of alcohol are formed, most of which will evaporate during the bread baking process. Therefore, you won't get drunk by eating bread!
Saccharomyces is responsible for the alcohol fermentation of wines. Grape juice contains naturally high levels of sugars. These sugars are converted into alcohol and carbon dioxide. Natural fermentation can yield wines with an alcohol up to 16 percent.