Lactic acid fermentation is carried out by many bacteria, most notably by the lactic acid bacteria used in the production of yogurt, cheese, sauerkraut, and pickles. Some animal cells such as muscle cells can also use fermentation for a quick burst of energy. Alcohol Fermentation Alcohol fermentation also begins with glycolysis to produce two molecules of pyruvic acid, two molecules of ATP, and four electrons. Each pyruvic acid is modified to acetaldehyde and CO2. Two molecules of ethyl alcohol are formed when each acetaldehyde molecule accepts two electrons.
Alcohol fermentation is carried out by many bacteria and yeasts .
In industry, as well as other areas, the uses of fermentation progressed rapidly after Pasteur's discoveries. Between 1900 and 1930, ethyl alcohol and butyl alcohol were the most important industrial fermentations in the world. But by the 1960s, chemical synthesis of alcohols and other solvents were less expensive and interest in fermentations waned. Questions can be raised about chemical synthesis, however. Chemical manufacture of organic molecules such as alcohols and acetone rely on starting materials made from petroleum.