Louis Pasteur discovered _________ in 1857.

Options

A. Fermentation
B. Pasteurization
C. Streptomycin
D. Tetracyclins

Answer

**Step-by-Step Solution:**

1. **Identify the Scientist and Year:** The question asks about what Louis Pasteur discovered in 1857.

2. **Recall the Discovery:** Louis Pasteur is well-known for his work in microbiology and his discovery related to the process of pasteurization.

3. **Define Pasteurization:** Pasteurization is a technique used to sterilize liquids, particularly milk, by heating it to a specific temperature (72 degrees Celsius) for a short period (15 seconds) and then cooling it down. This process kills harmful microbes present in the liquid.

4. **Explain the Importance of Pasteurization:** The significance of pasteurization is that it prevents the growth of harmful microorganisms in food and beverages, making them safer for consumption.

5. **Conclude with the Answer:** Therefore, the answer to the question is that Louis Pasteur discovered **pasteurization** in 1857.

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