Which of the following bacteria convert milk into curd?

Options

A. Propioni bacterium
B. Lactobacillus
C. Streptococcus
D. Bacillus

Answer

**Step-by-Step Solution:**

1. **Understanding the Process**: The question asks which bacteria convert milk into curd. To answer this, we need to understand the fermentation process that occurs when milk is turned into curd.

2. **Identifying the Key Component**: The main component in milk that is converted during this process is lactose, a sugar found in milk.

3. **Role of Bacteria**: The bacteria responsible for this conversion is known for producing lactic acid from lactose. This lactic acid is crucial as it lowers the pH of the milk, leading to the coagulation of proteins and the formation of curd.

4. **Identifying the Bacteria**: The specific bacterium that performs this function is called **Lactobacillus**. This bacterium ferments lactose into lactic acid, which is what causes the milk to curdle.

5. **Conclusion**: Therefore, the bacteria that convert milk into curd is **Lactobacillus**.

**Final Answer**: Lactobacillus

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