Question

how curd is formed from milk

Answer 1

Milk is converted into curd or yogurt by the process of fermentation. Milkconsists of globular proteins called casein. The curd forms because of the chemical reaction between the lactic acid bacteria and casein. During fermentation, the bacteria use enzymes to produce energy (ATP) from lactose.

Answer 2

When lactobacilli bacteria is add to milk, it ferments milk. The sugerin mulk is converted into lactose increasing pH of milk.