Question

How curd is different from milk.

Answer 1

Milk and Curd

1. Milk consists of globular proteins called casein.
2. Milk is converted into curd by the process of fermentation.
3. The curd forms because of a chemical reaction between lactic acid bacteria and casein.
4. During Fermentation, the bacteria use enzymes to produce Adenosine trisphosphate $\left(\mathrm{ATP}\right)$ from lactose.
5. The byproduct of $\left(\mathrm{ATP}\right)$ production is lactic acid.
6. Milk is slightly acidic in nature, and its $\mathrm{pH}$ value is $6$.
7. When milk is converted into curd by the action of bacteria the medium becomes more acidic thus there is a change in its $\mathrm{pH}$ value. The $\mathrm{pH}$ value decreases as milk is converted into curd which becomes a more acidic medium.

Therefore, by the process of fermentation milk is converted into curd.