AP BIOLOGY

Detailed explanation-1: -Yeasts in bread dough use alcoholic fermentation and produce carbon dioxide gas. The gas forms bubbles in the dough, which cause the dough to expand. The bubbles also leave small holes in the bread after it bakes, making the bread light and fluffy.

Detailed explanation-2: -Alcoholic fermentation is a complex biochemical process during which yeasts convert sugars to ethanol, carbon dioxide, and other metabolic byproducts that contribute to the chemical composition and sensorial properties of the fermented foodstuffs.

Detailed explanation-3: -In a bread dough, oxygen supply is limited and the yeast can only achieve partial fermentation and instead of carbon dioxide and water being given off, carbon dioxide and alcohol are produced. This is called alcoholic fermentation.

Detailed explanation-4: -During fermentation, carbon dioxide is produced and trapped as tiny pockets of air within the dough. This causes it to rise. During baking the carbon dioxide expands and causes the bread to rise further.

Detailed explanation-5: -Bread fermentation is the anaerobic biological method that changes sugars and starches into a different form. When this process is used in baking bread and the creation of dough, the fermentation facilitates the yeast and bacteria changing sugars and starches into carbon dioxide.