a = Glyceraldehyde – 3 – phosphate

b = PEP (Phosphoenol pyruvic acid)

c = C₂H₅OH

d = Lactic acid

The process is known as fermentation. After the glycolysis process, which doesn’t require oxygen. We obtain pyruvic acid. Now if the cells have oxygen present, i.e., aerobic conditions are present in the cell, then this pyruvic acid goes on to the citric acid cycle or tricarboxylic cycle in the mitochondria. But when there are anaerobic conditions the pyruvic acid gets converted to either lactic acid and it is known as homolactic fermentation. For examples, when our muscles do not receive oxygen, then homolactic fermentation occurs.

Also in some micro-organisms which are naturally anaerobic like yeast. They form C₂H₅OH and release CO₂. This is known as alcoholic fermentation.

Two Applications of fermentation:

i) Fermentation is widely used for the production of alcoholic beverage products like Whisky, Beer, etc.

ii) Fermentation is widely used for the production of acids like citrus acid, lactic acid, alpha- amylase, etc.