1. Fermentation:
* Yeast is a single-celled fungus that feeds on sugars. When added to dough, it consumes the sugars in flour and produces carbon dioxide (CO2) and ethanol (alcohol) as byproducts.
* This process is called fermentation.
2. Rising the Dough:
* The CO2 gas produced during fermentation gets trapped within the dough's gluten structure, causing the dough to expand and rise.
* This creates the characteristic airy texture of bread.
3. Flavor and Aroma:
* The ethanol produced also evaporates during baking, leaving behind subtle flavor and aroma that contribute to the overall taste of bread.
4. Improving Texture:
* Yeast fermentation also helps break down complex starches in flour into simpler sugars, making the dough more digestible.
* It also develops gluten in the dough, making it more elastic and easier to work with.
5. Other Microorganisms:
* While yeast is the primary microorganism involved, other microbes like lactic acid bacteria can also be present in sourdough bread. These bacteria contribute to the unique flavor and tanginess of sourdough.
In short, yeast is a crucial ingredient in bread making, responsible for the rise, texture, flavor, and aroma of the final product.
