Baker's yeast is

Options

A. S. cerevisiae
B. S. ludwigii
C. S. octosporus
D. Schizosaccharomyces

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about "Baker's yeast." The scientific name for baker's yeast is **Saccharomyces cerevisiae**.

2. **Understand its Role**: Saccharomyces cerevisiae is primarily used in the **bakery industry**. It plays a crucial role in the fermentation process.

3. **Anaerobic Fermentation**: This yeast undergoes **anaerobic fermentation**, which means it can convert sugars into alcohol and carbon dioxide in the absence of oxygen.

4. **Chemical Reaction**: During fermentation, Saccharomyces cerevisiae converts glucose (a carbohydrate) into **ethanol (C2H5OH)** and **carbon dioxide (CO2)**. The reaction can be summarized as:
\[ \text{Glucose} \rightarrow \text{Ethanol} + \text{Carbon Dioxide} \]

5. **Application in Baking**: The carbon dioxide produced during fermentation is what causes the dough to rise. This gas gets trapped in the dough, leading to the **fluffiness** of baked products like bread, cakes, and cookies.

6. **Conclusion**: Therefore, baker's yeast is **Saccharomyces cerevisiae**, and its fermentation process is essential for both the baking and beverage industries.

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