Final answer:
Fermentation in yeast dough occurs when yeast metabolizes sugars, such as glucose, into ethanol and carbon dioxide. This process causes dough to rise and is essential for producing the light and airy texture of bread.
Step-by-step explanation:
Fermentation takes place in yeast dough when the yeast acts upon sugars such as glucose. Alcoholic fermentation is a biochemical process that enables yeast cells to live in the absence of oxygen. During this process, the sugars in the dough are converted to ethanol (C2H5OH) and carbon dioxide (CO2). The carbon dioxide gas forms bubbles in the dough, which cause the dough to rise and create the classic light and fluffy texture of baked bread. The ethanol, on the other hand, generally evaporates during the baking process.
Yeast is a single-celled eukaryotic organism that carries out this fermentation efficiently and reliably, making it an ideal choice for bread baking. Not only does the generated CO2 leaven the dough, but the byproducts of this fermentation contribute to the flavor profile of the bread.
The balanced chemical reaction for the fermentation of glucose by yeast is as follows:
C6H12O6 → 2 C2H5OH + 2 CO2