Which bacterium helps in the production of 'Swiss cheese'?

Options

A. Propionibacterium sharmanii
B. Trichoderma polysporum
C. Saccharomyces cerevisiae
D. Aspergillus niger

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which bacterium is involved in the production of Swiss cheese.

2. **Identifying the Options**: The options provided are:
- Propionibacterium sharmanii
- Trichoderma polysporum
- Saccharomyces rivatiae
- Aspergillus niger

3. **Analyzing Each Option**:
- **Propionibacterium sharmanii**: This is a bacterium known for its role in cheese production, particularly Swiss cheese, due to its ability to produce carbon dioxide (CO2) during fermentation.
- **Trichoderma polysporum**: This is a fungus, not a bacterium, and is not involved in cheese production.
- **Saccharomyces rivatiae**: This is a yeast, not a bacterium, and is typically associated with fermentation processes like brewing.
- **Aspergillus niger**: This is another fungus and is not involved in cheese production.

4. **Conclusion**: The only bacterium listed that is responsible for the production of Swiss cheese is **Propionibacterium sharmanii**.

5. **Final Answer**: The bacterium that helps in the production of Swiss cheese is **Propionibacterium sharmanii**.

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