Question

Assertion: Yeasts, such as Saccharomyces Cerivisiae are used in baking industry.
Reason: Carbon dioxide produced during fermentation causes bread dough to rise by thermal expansion.

• A. Both assertion and reason are true and reason is the correct explanation for assertion
• B. Both reason and assertion are true but reason is not correct explanation for assertion
• C. Assertion is true but reason is false
• D. Assertion is true but reason is false

Answer 1

The correct option is A

Both assertion and reason are true and reason is the correct explanation for assertion

Explanation:

• Baker’s yeast (Saccharomyces Cerivisiae) is added to flour during kneading.
• Yeast secreted enzymes like amylase (changes some starch to maltase), maltose (maltose to glucose) and zymase (glucose to ethyl alcohol and carbon dioxide).
• The dough swells up or leavens. Leavened dough is baked and both alcohol and carbon dioxide evaporate.
• The bread becomes soft and porous.

• The carbon dioxide produced in these reactions causes the dough to rise (ferment), and the alcohol produced mostly evaporates from the dough during the baking process.

• Thousands of tiny bubbles, each surrounded by a thin film of gluten form cells inside the dough piece. The increase in dough size occurs as these cells fill with gas.