Which Microorganisms grow in milk and convert it to curd ?

Answer

**Step-by-Step Solution:**

1. **Identify the Sugar in Milk**: Milk contains a sugar called lactose, which is the primary carbohydrate present in milk.

2. **Role of Microorganisms**: The conversion of milk to curd involves specific microorganisms known as lactic acid bacteria. These bacteria are responsible for the fermentation process.

3. **Fermentation Process**: When lactic acid bacteria act on lactose, they convert it into lactic acid through a process called lactic acid fermentation.

4. **pH Reduction**: The production of lactic acid lowers the pH of the milk. This change in pH is crucial for the next step in the curd formation process.

5. **Coagulation of Proteins**: The decrease in pH causes the milk protein, casein, to coagulate or curdle. This means that the proteins begin to clump together and form solid curds.

6. **Formation of Curd**: As the casein coagulates, curd is formed, which is the solid part of the milk that we recognize as curd.

7. **Final Answer**: Therefore, the microorganisms that grow in milk and convert it into curd are known as lactic acid bacteria.

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