2 ATP molecules are formed from the breakdown of one glucose molecule in alcoholic fermentation as well as in lactic acid fermentation. this is an insufficient method of production of ATP but despite it has its importance. this method is also used to make wine from grapes.

ATP production in fermentation of glucose
The fermentation of glucose to either alcohol or lactic acid is a process that occurs in the absence of oxygen. During this process, ATP is generated through glycolysis, a metabolic pathway that breaks down glucose into pyruvate.

Alcohol fermentation
- In alcohol fermentation, glucose is converted into ethanol and carbon dioxide by yeast or some bacteria.
- In this process, 2 molecules of ATP are produced per molecule of glucose during glycolysis.
- Additionally, 2 molecules of ATP are consumed during the preparatory phase of glycolysis, resulting in a net gain of 2 ATP molecules per glucose molecule.

Lactic acid fermentation
- In lactic acid fermentation, glucose is converted into lactic acid by certain bacteria and muscle cells.
- Like alcohol fermentation, 2 molecules of ATP are produced per molecule of glucose during glycolysis.
- However, there is no further ATP consumption, resulting in a net gain of 2 ATP molecules per glucose molecule.

Conclusion
In both alcohol and lactic acid fermentation, 2 molecules of ATP are produced per molecule of glucose. This ATP production is essential for providing energy to the cell in the absence of oxygen. While fermentation is less efficient in terms of ATP production compared to aerobic respiration, it is a crucial process for organisms that cannot rely on oxygen for energy production.