What type of fermentation occurs in bread making?

In bread making, the primary type of fermentation that occurs is yeast fermentation, which is crucial for the leavening process. When yeast is added to the dough, it consumes the sugars present and produces carbon dioxide and alcohol as byproducts. This carbon dioxide is what causes the dough to rise, creating air pockets that result in the light and fluffy texture characteristic of bread.

Yeast fermentation also contributes to the development of flavor in the bread as it produces various compounds during the fermentation process. While other types of fermentation, such as alcohol fermentation, may occur alongside yeast fermentation, the primary driver of the fermentation process in bread is indeed the activity of yeast itself. This unique ability of yeast to ferment sugars and produce gas and alcohol is what fundamentally distinguishes yeast fermentation in the context of bread making.

In contrast, the other types of fermentation listed do not play a pivotal role in bread making. Acetic acid fermentation and lactic acid fermentation are more relevant to processes involving vinegar and certain dairy products, respectively, rather than the typical yeast-driven process essential for bread.