Why Yeast is used in baking industry?

Yeast is indispensable in the baking industry because it produces carbon dioxide gas through fermentation, which causes bread dough to rise and develop its characteristic light, airy, and fluffy texture. When yeast (Saccharomyces cerevisiae) is mixed with flour, water, and sugar, it metabolizes the sugars present in the dough and releases carbon dioxide bubbles that become trapped in the gluten network formed by wheat proteins. This process, called leavening, creates thousands of tiny air pockets throughout the dough, expanding its volume and giving baked bread its soft, spongy crumb structure.

Beyond leavening, yeast fermentation also contributes complex flavors and aromas to bread through the production of organic compounds during the fermentation process. The small amount of alcohol produced during fermentation evaporates during baking, while the carbon dioxide creates the porous structure. Commercial bakeries use different yeast forms—active dry yeast, instant yeast, or fresh yeast—depending on their production needs and timelines. Without yeast, breads would be dense and flat like unleavened products such as tortillas or matzo. Temperature control is crucial in baking because yeast works best at warm temperatures (around 25-30°C) but dies at high baking temperatures, having already fulfilled its leavening role.