Baking: Yeast Raised Products  Yeast  Single-celled fungi  Enzyme zymase:  Produces CO 2 and alcohol  Uses sugar (glucose or fructose) as substrate  Four types for baking:  Active dry  Quick Rise  Instant  Cake

Baking: Yeast Raised Products  Yeast continued…  Temperature requirements  105-110°F or 41-43°C for rehydration  Must not exceed 140°F (60°C)  Requires a food source to multiply  Proofing  A test for viability before baking  Mix with warm H 2 O and sugar  CO 2 should be released

Baking: Yeast-Raised Products  Flour  Different attributes depend upon:  Protein content  Gluten formation potential  Types:  Bread flour  Cake flour  All-purpose flour  Whole-wheat flour

Baking: Yeast-Raised Products  Flour continued…  Bread flour  Hard wheat  High gluten  Strong and elastic  Cake flour  Soft wheat  Low gluten  Smooth texture

Baking: Yeast-Raised Products  Flour continued…  All-purpose flour  Slightly weaker than bread flour  Multi-purpose  Whole-wheat flour  Contains gluten

Baking: Yeast-Raised Products  Other ingredients  Liquids  Water  Potato cooking water  Milk  Sugar  Facilitates yeast growth  Contributes to browning reaction

Baking: Yeast-Raised Products  Other ingredients continued…  Salt  Flavor enhancer  Allows gluten to stretch for a larger volume  Fat (optional)  Increases tenderness by shortening gluten  Aids in browning reaction  Decreases staling

Baking: Yeast-Raised Products  Preparation and Baking  Manipulation  Protein absorbs H 2 O  Gluten development occurs  Fermentation  CO 2 given off by yeast  Aeration of dough results  Volume doubles—fermentation is over

Baking: Yeast-Raised Products  Preparation and Baking continued…  Punching down  When size has doubled  Relieves stress on gluten strands  Squeezes out excess CO 2  Proofing  Final rising  Takes less time than 1 st proof  More yeast than in 1 st proof

Baking: Yeast-Raised Products  Preparation and Baking continued…  Cooling  Let cool before cutting  Storage  Do not refrigerate!

 Either freeze (long term) or keep at room temp.