In baking, what is the function of yeast?

The function of yeast in baking is to leaven bread. Yeast is a living organism that ferments sugars present in the dough and produces carbon dioxide gas and alcohol as by-products. The carbon dioxide gas gets trapped in the dough, causing it to rise and become light and airy. This process is essential for creating the desired texture in bread and other baked goods, allowing them to achieve a fluffy and well-developed structure.

While yeast can contribute to the overall flavor of the bread due to the fermentation process, its primary role in baking is specifically related to leavening. Other options listed do not describe the fundamental purpose of yeast in the context of baking. For instance, although some might think yeast could enhance flavor or sweeten dough, those functions do not define yeast's main purpose as a leavening agent. Thicken mixtures is generally associated with other ingredients like starches or gums, rather than yeast. In summary, leavening is the key function of yeast, making it essential for the baking process.