Which gas is responsible for the puffed - up appearance of dough?

Options

A. Streptococcus
B. Staphylococcus
C. Lactobacillus
D. Saccharomyces

Answer

**Step-by-Step Solution:**

1. **Identify the Organism Involved**: The organism responsible for the puffed-up appearance of dough is yeast, specifically the species Saccharomyces cerevisiae.

2. **Understand the Role of Yeast**: Yeast is a eukaryotic single-celled microorganism that belongs to the kingdom Fungi. It plays a crucial role in the fermentation process.

3. **Explain the Fermentation Process**: During fermentation, yeast converts carbohydrates (sugars) into two main products: alcohol and carbon dioxide (CO2). This process is essential in baking and brewing.

4. **Focus on the Gas Produced**: The carbon dioxide gas produced during fermentation is what causes the dough to rise. As the yeast ferments the sugars, it releases CO2, which gets trapped in the dough.

5. **Conclusion**: The trapped carbon dioxide gas increases the volume of the dough, giving it a puffed-up appearance. Therefore, the gas responsible for this effect is carbon dioxide (CO2).

**Final Answer**: The gas responsible for the puffed-up appearance of dough is carbon dioxide (CO2).

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