Possible Clues:

• It gets a rise out of dough
• What flatbreads lack
• Fungus able to convert sugar into alcohol
• It helps in making booze when put in still
• Sourdough starter component
• Ingredient in challah
• Fungus for baking and brewing
• What's helpful when you need to raise dough?
• Bread or beer ingredient
• Still dressing in the role of baker's helper