Which one is used for preparation of bread?

Options

A. Lactobacillus
B. Streptobacillus
C. Aspergillus
D. S. cerevisiae

Answer

**Step-by-Step Solution:**

1. **Identify the Options**: The question asks which microorganism is used for the preparation of bread. The options provided are Leptobacillus, Streptobacillus, Aspergillus, and Saccharomyces cerevisiae.

2. **Understand the Role of Each Microorganism**:
- **Leptobacillus**: Primarily involved in the fermentation of milk, not used for bread.
- **Streptobacillus**: Associated with cheese production, not relevant to bread making.
- **Aspergillus**: A type of fungus used in the production of citric acid, not for bread.
- **Saccharomyces cerevisiae**: Commonly known as baker's yeast, it is crucial in bread making.

3. **Explain the Function of Saccharomyces cerevisiae**:
- This yeast ferments sugars present in the dough, converting them into ethanol and carbon dioxide.
- The carbon dioxide produced causes the dough to rise, making the bread light and fluffy.

4. **Conclusion**: The correct answer is **Saccharomyces cerevisiae**, as it is specifically used in the preparation of bread due to its ability to produce carbon dioxide during fermentation.

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