Question

Lactic acid bacteria (LAB) grow in milk and convert it into curd. During growth, the LAB produces acids that

• A. coagulate and completely digest the milk proteins
• B. coagulate and completely digest the milk sugars
• C. coagulate and partially digest the milk proteins
• D. coagulate and partially digest the milk sugars

Answer 1

The correct option is C coagulate and partially digest the milk proteins

Curd is produced by the fermentation of milk by the lactic acid bacteria (LAB).

During curd preparation, a small amount of curd is added to the fresh milk and is kept undisturbed at a warm temperature. The small amount of curd added as an inoculum or starter contains millions of LAB. These bacteria grow in milk and breakdown the lactose sugar in the milk to lactic acid.

The lactic acid formed causes the coagulation and partial digestion of the milk proteins(casein) which precipitate as curd.
Thus, we can say that option c is correct.