Chapter 4:

1. Chapter 4: Fermentation © 2009 Cengage Learning. All Rights Reserved.

2. Fermentation • Fermentation = the breakdown of compound molecules in organic substances under the effect of yeast or bacteria • It starts when flour and water come into a contact • In baking, it occurs when some of the sugar or glucide is converted into alcohol and carbon dioxide under the effect of commercial or natural yeast and bacteria © 2009 Cengage Learning. All Rights Reserved.

3. Fermentation • Sugar Transformation • Flour contains various types of glucides • More complex glucides must be degraded by enzymes or organic substances • Less complex glucides are used as is © 2009 Cengage Learning. All Rights Reserved.

4. Fermentation:Sugar Transformation • Complex Glucides • Saccharose and Maltose • Represent 1% of flour • During the first 30 minutes of fermentation time, Enzyme breaks them down into simple sugars • Saccharose breaks down into glucose and Fructose • Maltose breaks down into glucose © 2009 Cengage Learning. All Rights Reserved.

5. Fermentation:Sugar Transformation • Very Complex Glucides • Starch • Represents 70% of flour • Two types: Amylose and Amylopectin • Amylose is broken down into maltose by beta amylase enzyme • Amylopectin is broken down into dextrin by alpha amylase enzyme, and dextrin is degraded into maltose © 2009 Cengage Learning. All Rights Reserved.

6. Fermentation:Sugar Transformation • Simple Glucides • Glucose and Fructose • Represent 0.5% of flour • First sugar to be used in the fermentation • Used within the first 30 minutes of the fermentation process • Easy transformation to alcohol and carbon dioxide • Starch is damaged during the milling process • Damaged parts of starch (from the milling process) absorb water, and triggers the enzymatic activity © 2009 Cengage Learning. All Rights Reserved.

7. Fermentation • Importance of Enzymatic Balance in the Flour • Alpha and Beta amylase enzymes naturally present in the flour • The germination of the wheat varies the amount of alpha amylase • When sprouting, the germ sends enzymes to the endosperm, which transform the complex components into smaller nutrients that are immediately usable by the germ © 2009 Cengage Learning. All Rights Reserved.

8. Fermentation • Effects of Fermentation Activity on Dough • Rising of the dough due to the carbon dioxide production • Internal accumulation of gas stretches the gluten structure of the dough • The dough’s impermeability, extensibility and elasticity, the gluten is capable to retain the gas © 2009 Cengage Learning. All Rights Reserved.

9. Fermentation • Effects of Fermentation Activity on Dough • Acidification of dough • pH lowers due to the production of organic acids • Delays staling of the dough and increase shelf life • More elasticity, less extensibility © 2009 Cengage Learning. All Rights Reserved.

10. Fermentation • Factors Affecting Fermentation • Amount of yeast • Amount of Salt and sugar • Temperature • Dough pH © 2009 Cengage Learning. All Rights Reserved.

11. Fermentation:Factors Affecting Fermentation • Amount of Yeast • The amount of yeast must be limited to control fermentation • Temperature • Yeast is highly active at higher temperature, and slower at lower temperature • Desired Dough Temperature: 76°F © 2009 Cengage Learning. All Rights Reserved.

12. Fermentation:Factors Affecting Fermentation • Amount of Salt and Sugar • Salt slows down fermentation activity • Generally, salt is 2% of the flour weight • A small amount of sugar (5%) speeds up the fermentation process (simple sugar = nutrients) • A larger amount (13% or more) will slow down fermentation © 2009 Cengage Learning. All Rights Reserved.

13. Fermentation:Factors Affecting Fermentation • Dough pH • Commercial yeast works best when pH is 4-6 • Natural yeast prefers lower pH © 2009 Cengage Learning. All Rights Reserved.

14. Fermentation • Relationship between Fermentation and Dough Handling • Bread characteristics are determined by the baking process • Baking process: Dough Handling (mixing, dividing, shaping, scoring, baking) and Fermentation Time (dough evolves by itself) • The baking processes are interconnected, and one affects on others © 2009 Cengage Learning. All Rights Reserved.

15. Fermentation • Relationship between First Fermentation and Mixing • A long fermentation provides increased flavor and shelf life to the final product • During mixing, the hook develops the gluten by stretching and folding • The longer the mixing, the stronger the gluten • Mixing time needs to be decreased to have a long fermentation time © 2009 Cengage Learning. All Rights Reserved.

16. Fermentation • Relationship between First Fermentation and Mixing • Short mixing time limits oxidation of the dough • Requires folding technique to compensate the under-developed gluten • Folding reorganizes the gluten structure • It expulses the gas accumulated in the dough • Relationship between First Fermentation and Dividing • Gluten strands become more fragile – avoid damaging the dough during dividing © 2009 Cengage Learning. All Rights Reserved.

17. Fermentation • Relationship between First Fermentation and Dividing • Gluten strands become more fragile – avoid damaging the dough during dividing • Relationship between Dough Characteristics and Pre-shaping • If the dough have insufficient or excessive strength, it can be corrected during pre-shaping © 2009 Cengage Learning. All Rights Reserved.

18. Fermentation • Relationship between Dough Characteristics and Shaping • The dough characteristics can be balanced during shaping: last opportunity • Relationship between Final Proof and Shaping • Dough shaped through machine takes longer time to ferment • Hand-shaped dough takes shorter time to proof © 2009 Cengage Learning. All Rights Reserved.

19. Fermentation • Relationship between Dough Characteristics and Scoring • Over-proofed dough: shallow scoring • Under-proofed dough: deep scoring • The way to score changes the appearance of the final product: choose the scoring according to the dough characteristics © 2009 Cengage Learning. All Rights Reserved.

20. Fermentation • Preferments • Dough or batter created from a portion of the total formula’s flour, water, yeast and sometimes salt • Improves bread quality, strength and aroma • Types of Preferments • Pre-fermented Dough • Poolish • Sponge • Biga © 2009 Cengage Learning. All Rights Reserved.

21. Types of Preferment • Pre-Fermented Dough • Dough made with flour, water, yeast and salt • A piece of dough from previous mix can be used as a pre-fermented dough • Poolish • Derived by Polish bakers • Choice of preferment for baguette dough • 100% hydration • Provides mild acidity and extensibility © 2009 Cengage Learning. All Rights Reserved.

22. Types of Preferments • Sponge • Used for pan bread production in England • Popularly used in enriched dough • Improves flavor and strength of the dough • Biga • From Italy • Traditionally contains 50-55% water, but it varies • Provides dough strength © 2009 Cengage Learning. All Rights Reserved.

23. Preferments • Advantages and Drawbacks of Preferment • Advantages • Gas Production • Alcohol Production • Acid Production © 2009 Cengage Learning. All Rights Reserved.

24. Fermentation:Preferments • Advantages and Drawbacks of Preferment • Drawbacks • Additional work required • Extra space for storage (refrigerated/room temp) • Potential inability to plan exact amount of preferment © 2009 Cengage Learning. All Rights Reserved.

25. Preferments • Technical Considerations • Mixing Preferments • Stiff Preferment: Mix on first speed for 5 – 8 minutes • Liquid Preferment: Mix with a paddle attachment © 2009 Cengage Learning. All Rights Reserved.

26. Fermentation:Preferments • Technical Considerations • Incorporation in the Final Dough • Timing and Quantity • Secondary Effects of Preferment • Enzyme provokes sugar and protein degradation • Amylase and Protease © 2009 Cengage Learning. All Rights Reserved.

27. Fermentation • Sourdough • By accident, first created in Egypt between 4000-3000 BCE. • General Sourdough Process • Start a culture of microorganisms and increase the quantity to ferment the dough © 2009 Cengage Learning. All Rights Reserved.

28. Sourdough • Microorganisms Involved in the Sourdough Process • Yeast and Bacteria • Found in air, water, flour, etc • Yeast transforms simple sugars to alcohol and gas • Bacteria converts certain sugars into lactic and acetic acid © 2009 Cengage Learning. All Rights Reserved.

29. Sourdough • Starting a Culture • A controlled culture of microorganisms requiring food (flour), water and oxygen • Organic Flour and the addition of rye or whole wheat flour will increase micro organism activity © 2009 Cengage Learning. All Rights Reserved.

30. Fermentation:Sourdough • Culture Elaboration • Both aerobic and anaerobic activity of microorganisms (yeast and bacteria) • Stronger flora flourish and become established (natural selection) • Culture is “fed” at predetermined intervals to maintain activity of microorganisms © 2009 Cengage Learning. All Rights Reserved.

31. Fermentation:Sourdough • From Starter to Levain • Starter is elaborated until needed in formula • Levain is the preferment to be used to leaven final dough • If more activity is needed to achieve the mature levain, the quantity of starter may be increased in the levain feeding © 2009 Cengage Learning. All Rights Reserved.

32. Fermentation:Sourdough • Perpetuating the Culture • Option 1: remove a piece of the final dough before the addition of the salt • Option 2: increase levain quantity and remove required quantity of started to perpetuate • More consistent results occur when the starter is taken from the levain © 2009 Cengage Learning. All Rights Reserved.

33. Fermentation:Sourdough • Factors Affecting Culture Characteristics • Hydration: water content affects flora activity • Stiff culture will have tendency to develop more acetic acidity (more acidic flavor) • Liquid culture will increase the production of lactic acidity (less acidic flavor) © 2009 Cengage Learning. All Rights Reserved.

34. Fermentation:Sourdough • Factors Affecting Culture Characteristics • Temperature • 85°F (29°C) to 90F (32°C) favors bacterial activity and the production of lactic acidity, but fermentation is more difficult to control • 77F (25°C) optimizes fermentation activity, the development of the dough, and the production of aromas. © 2009 Cengage Learning. All Rights Reserved.

35. Fermentation:Sourdough • Factors Affecting Culture Characteristics • Flour • Enzyme and bran content determine the amount of simple sugar and minerals available for the microorganisms • Higher extraction flours provide better activity and higher acid production © 2009 Cengage Learning. All Rights Reserved.

36. Fermentation:Sourdough • Factors Affecting Culture Characteristics • Salt • 0.1 percent can be beneficial for a culture with high protease activity • More than 0.1 percent can inhibit the activity of some microorganisms. © 2009 Cengage Learning. All Rights Reserved.

37. Fermentation:Sourdough • Maintaining the Culture • Consistency • Feedings should be regulated: ratio, type and temperature of ingredients. Mixing and storage. • Sanitation • Always use clean equipment and practice good hygiene. • Contamination • Prevent contamination from commercial yeast. © 2009 Cengage Learning. All Rights Reserved.

38. Fermentation:Sourdough • Troubleshooting Sourdough Culture • Too little Acidity/Too much Acidity • Lack of development in the bread • Lack of strength in the levain. © 2009 Cengage Learning. All Rights Reserved.

39. Fermentation:Sourdough • Use in Final Dough • Proportion of levain • Related to dough and bread characteristics • Strength • Flavor (acidity level) • Use for different types of product • Possibility to develop different cultures with different characteristics • Whole Wheat, Rye • Sweet dough © 2009 Cengage Learning. All Rights Reserved.

40. Fermentation • Fermentation Process Conclusion • Fermentation affects flavor, appearance and keeping qualities of bread. • From poolish to sourdough, the baker has a lot to consider in terms of flavor, production schedule, and technical considerations. • The baker must learn to evaluate dough at all stages to have a solid understanding of the product and end subsequent end results. © 2009 Cengage Learning. All Rights Reserved.

41. Retarding Process • Retarding: • stopping the fermentation of the dough at various points in the process • Technical Considerations • Temperature • Gas Production • Gas Retention • Natural Dough Degradation © 2009 Cengage Learning. All Rights Reserved.

42. Retarding Process:Technical Considerations • Temperature • Ferments in baking are sensitive to temperature. • Optimal temperature for fermentation is 74°-80°F. • At lower temperatures, ferments slow down their metabolism. • When the temperature reaches 40°F (4°C), ferments become dormant and most activity is stopped. © 2009 Cengage Learning. All Rights Reserved.

43. Retarding Process:Technical Considerations • Gas Production • Depends on temperature of retarding process and quantity of yeast. • Freshness and quality of the yeast is important. • In a sourdough process, gas production will depend on the culture fermentation activity. • Liquid vs. Stiff cultures © 2009 Cengage Learning. All Rights Reserved.

44. Retarding Process:Technical Considerations • Gas Retention • The goal of the retarding process is to delay as long as possible the point where the gluten reaches maximum extensibility and breaks under the pressure of the gas. • A short first fermentation time is necessary to delay the point where the dough reaches its gas retention limit. • Flour with low starch damage slows fermentation activity. • To delay gas production at the beginning of the process, the DDT is 73°F (23°C). © 2009 Cengage Learning. All Rights Reserved.

45. Retarding Process:Technical Considerations • Natural Dough Degradation • Occurs when flour and water are put in contact and it continues as the fermentation progresses. • Most dough degradation happens because of protease. • To delay degradation start with dough that is strong enough to withstand retarding. • Some adaptations can be made during mixing. • Hydration can be slightly lower • Stiffer dough will provide a stronger gluten structure. • Mixing time must be calculated to sufficiently develop the dough and obtain a strong organized gluten structure. © 2009 Cengage Learning. All Rights Reserved.

46. Retarding Process:Basic Retarding Techniques • Delayed First Fermentation • After mixing, retard dough at 45°F (7°C) to 48°F (9°C). The retarding time can last from 12 to 18 hours. • After retarding, take the dough out of the retarder and divide it right away, or wait about 1 hour before scaling. • Divide and preshape as normal. A longer resting time will be necessary to allow the dough to warm up and restart fermentation. • Complete normal shaping and final proof and bake at the usual temperature and time © 2009 Cengage Learning. All Rights Reserved.

47. Retarding Process:Basic Retarding Techniques • Delayed First Fermentation: Advantages • At 45°F (7°C) to 48°F (9°C) gas and acidity production is still happening at a lower rate but for a longer period of time. • When good quality flour is used, there is no need for dough conditioners such as ascorbic acid, keeping the product labeling cleaner. • Because the dough is retarded in bulk before shaping, no blisters are formed during baking. • The baker can organize production to offer customers fresh bread all day long without mixing too many batches of dough. © 2009 Cengage Learning. All Rights Reserved.

48. Retarding Process:Basic Retarding Techniques • Delayed First Fermentation: Drawbacks • This technique requires a retarder with enough capacity to store a large amount of dough. • The bread cannot be baked immediately after retarding. Three to four hours are necessary to divide, shape, proof and bake the bread. © 2009 Cengage Learning. All Rights Reserved.

49. Retarding Process • Slow Final Proof • Mix to achieve between an improved mix and an intensive mix • The amount of fresh yeast: 0.8 to 1 percent. • A longer fermentation time calls for a lower percentage of yeast. • Preferment is advised, and the DDT is 73°F (23°C). © 2009 Cengage Learning. All Rights Reserved.

50. Retarding Process:Basic Retarding Techniques • Slow Final Proof • Method • After mixing, allow the dough to ferment 20 to 30 minutes and then divide, preshape and shape as normal • Place the shaped dough in the retarder set at 50°F (10°C). • Retard for 12 to 15 hours and bake directly from the retarder © 2009 Cengage Learning. All Rights Reserved.