Lactobacilli are used for making yoghurt from milk.

Question

Give scientific reasons:

Lactobacilli are used for making yoghurt from milk.

Answer 1

• Lactobacilli convert lactose, the sugar in the milk, into lactic acid. This process is called fermentation. 
• As a result, the pH of milk decreases causing coagulation of milk proteins.
• Thus, milk proteins are separated from other constituents of milk and milk changes into yoghurt. 
• Yoghurt has a specific sour taste due to lactic acid. The low pH destroys harmful microbes present in the milk. Therefore, Lactobacilli are used for making yoghurt from milk.