Question

In the presses of making bread the role of the yeast added is to make the bread rise by producing CO2 in ?

A. Fermentation
B. Respiration
C. Oxidation
D. Photosynthesis

Answer 1

The yeast added to bread dough is responsible for producing CO2 through fermentation, a process that helps the bread rise by creating gas bubbles within the dough, leading to its characteristic light and fluffy texture.

Step-by-step explanation:

In the process of making bread, the role of the yeast added is to make the bread rise by producing CO2 in fermentation. Yeast performs alcoholic fermentation, which operates in the absence of oxygen. During fermentation, sugars such as glucose are converted into ethanol and carbon dioxide (CO2). This CO2 production is vital as it forms bubbles in the dough, causing it to expand and rise, creating the characteristic texture of bread. Yeasts are favored for this process in bread making because they can ferment rapidly and predictably under various conditions, making them a reliable means to leaven bread.

The balanced chemical reaction for the fermentation of glucose by yeast is:
C6H12O6 → 2 C2H5OH + 2 CO2

Here, one molecule of glucose (C6H12O6) is converted into two molecules of ethanol (C2H5OH) and two molecules of carbon dioxide (CO2), contributing to the leavening of the dough.