Pasteurisation is done at:

Options

A. `100^@ C`
B. `30^@` C
C. `70^@ C`
D. `45^@ C`

Explanation

**Step-by-Step Solution:**

1. **Understanding Pasteurization**: Pasteurization is a process named after Louis Pasteur, which involves heating liquids to a specific temperature to kill harmful pathogens without significantly altering the liquid's taste or nutritional value.

2. **Identifying the Purpose**: The main goal of pasteurization is to eliminate harmful microorganisms, particularly in food products like milk and juices, to make them safe for consumption.

3. **Temperature Considerations**: The question provides four temperature options: 100°C, 30°C, 70°C, and 45°C. We need to determine which of these temperatures is commonly used for pasteurization.

4. **Evaluating the Options**:
- **100°C**: This is the boiling point of water and is too high for pasteurization, as it would alter the taste and nutritional content of the liquid.
- **30°C**: This temperature is too low and would not effectively kill pathogens.
- **70°C**: This temperature is known to be effective for pasteurization, as it can kill most harmful bacteria without boiling the liquid.
- **45°C**: This temperature is also too low to effectively kill pathogens.

5. **Conclusion**: Based on the evaluation, the correct temperature for pasteurization is **70°C**.

**Final Answer**: Pasteurization is done at **70 degrees Celsius**.

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