Yeast is added to the dough during the preparation of bread because it produces

Yeast is added to the dough during the preparation of bread because it produces carbon dioxide. Yeast is a type of fungus that feeds on sugars and produces carbon dioxide gas as a byproduct. When added to bread dough, the yeast feeds on the sugars in the dough and produces carbon dioxide gas, which gets trapped in the dough and causes it to rise. This process is called fermentation, and it is what gives bread its light, airy texture. The carbon dioxide gas also helps to make the bread more flavorful by creating small pockets in the dough where flavor compounds can accumulate.