Pasteurisation is

Options

A. Heating of liquid at `65^(@)C`
B. Heating of liquid between `65^(@)-80^(@)C` followed by rapid cooling
C. Heating of solids at `65^(@)C`
D. None of these

Answer

**Step-by-Step Solution:**

1. **Definition of Pasteurization**: Pasteurization is a process of heating liquids to eliminate pathogens and extend shelf life. It is primarily used for liquid food products.

2. **Temperature Range**: The process typically involves heating the liquid to a temperature between 65°C and 80°C. This range is effective in killing harmful microorganisms without significantly affecting the taste or nutritional value of the food.

3. **Rapid Cooling**: After heating, the liquid is rapidly cooled. This step is crucial as it helps to prevent the growth of any remaining bacteria that could spoil the food.

4. **Application**: Pasteurization is commonly applied to milk and other dairy products, as well as juices and some alcoholic beverages. The goal is to make these products safe for consumption while maintaining their quality.

5. **Historical Context**: The process is named after the French scientist Louis Pasteur, who developed it in the 19th century as a method to prevent spoilage and improve food safety.

6. **Conclusion**: In summary, pasteurization is a heat treatment process that involves heating liquids to a specific temperature range followed by rapid cooling to eliminate pathogens and extend shelf life.

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