Question

curd formation takes place only in Luke warm milk

Answer 1

When small amount of curd is added to warm milk, the bacteria in the curd divides to convert the rest of the milk also into curd. If the curd is not transferred to a cool place, then curd tuns sour because the bacteria continue to multiply and produce more lactic acid.

Answer 2

During fermentation, the bacteria use enzymes to produce energy (ATP) from lactose. The byproduct of ATP production is lactic acid. Lactic acid acts on the globular proteins present in the milk and denatures them. This denaturation destroys the tertiary and quaternary structures of proteins and the globular proteins are converted into fibrous proteins thus giving a thick texture to the milk due to coagulation of the proteins.

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