The vitamin whos content increases following the conversion of milk into curd by lactic acid bacteria is

Options

A. vitamin C
B. vitamin D
C. vitamin 1D_(12)`
D. vitamin E

Answer

To solve the question regarding which vitamin's content increases following the conversion of milk into curd by lactic acid bacteria, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Process**:
- When milk is converted into curd, lactic acid bacteria (LAB), primarily Lactobacillus, are involved in this fermentation process. These bacteria convert lactose (the sugar present in milk) into lactic acid.

2. **Identifying the Vitamins**:
- The question provides four options:
1. Vitamin C
2. Vitamin D
3. Vitamin B12
4. Vitamin E

3. **Analyzing Each Vitamin**:
- **Vitamin C**: Known for its role in wound healing and is found in citrus fruits. It does not play a role in the fermentation of milk into curd.
- **Vitamin D**: Important for bone health and is associated with calcium metabolism. It does not increase during the fermentation process.
- **Vitamin B12**: This vitamin is produced by certain bacteria, including lactic acid bacteria. It is known to be present in fermented dairy products like curd.
- **Vitamin E**: Functions as an antioxidant and does not have a direct relation to the fermentation of milk.

4. **Conclusion**:
- Among the options, Vitamin B12 is the one that increases in content when milk is converted into curd by lactic acid bacteria. Therefore, the correct answer is **Vitamin B12** (Option 3).

### Final Answer:
The vitamin whose content increases following the conversion of milk into curd by lactic acid bacteria is **Vitamin B12**.

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