What You Need to Know
During fermentation, yeast metabolizes sugars to produce CO₂ and ethanol, while lactic acid bacteria convert sugars to lactic acid and acetic acid, lowering pH and influencing crumb structure. The balance of yeast and bacteria, modulated by temperature, hydration, and flour type, determines the acidity, flavor profile, and dough extensibility.
The Science
Primary Reaction
Carbohydrate fermentation by yeast and lactic acid bacteria producing CO₂, lactic acid, acetic acid, and flavor compounds.