Presentation of Sourdough
• History
• Understanding sourdough process
• Creating a culture
• Maintaining it (feeding process)
• Factors that can affect characteristics of the levain
• Using the culture in the final dough

The feeding chart

History of sourdough

1. First bread in Egypt 3 or 4 thousand years BC
2. Process developed by the Roman and brought all over Europe
3. USA and the "49 ers"
4. Process widely used until the mid 1800s when commercial starts to become available to
   bakers
5. But even then, the sourdough process was still used by bakers that couldn't get commercial
   yeast

Understanding sourdough process

General concept

How to start a sourdough culture

1. Different ingredients
2. Different consistency of the culture

1. Nutrients
2. Water
3. Oxygen

Factors affecting the elaboration

Bacteriological changes happening during the culture elaboration

1. Acidity
2. Lack of oxygen
3. Type of nutrients

1. Population of microorganism starts to grow

1. Between yeast and bacteria

1. Production of gas
2. Production of acidity
3. Lactic acidity
4. Acetic acidity
Main types of micro-organism
5. Wild yeast
1. Different than commercial yeast
6. Bacteria
1. Homofermentative
2. Heterofermentative
7. Origin
1. Principally coming from the flour
2. Other places as well
Role of the micro-organism
8. Wild yeast
1. Gas production
2. Alcohol production
9. Homofermentative bacteria
1. Lactic acidity production
10. Heterofermentative bacteria
1. Lactic acidity production
2. Acetic acidity production
3. Gas production
Determining when the culture is ready to be used
11. After the all elaboration process, the culture should be active enough to generate
    fermentation
1. Should rise about 3 times its initial volume after 8 hours
12. The surface gives also some indication
1. Should dome with a slight collapsing in the center
13. At this time the culture becomes a starter
Feeding the starter
14. To maintain the good activity of the yeast and bacteria
1. Feeding supplies nutrients, water and oxygen
15. To increase the quantity of starter
1. Have enough levain to ferment the final dough
16. To perpetuate the culture
Perpetuating the starter
17. Three possibilities
1. Taking the starter from the levain a safe technique
2. Taking the starter from a "Mother" a very safe technique and the possibility to work with
   different flour
3. Taking the starter from the final dough a more risky technique
Different feeding processes
18. One feeding a day
19. Two feeding a day
20. Three feeding a day
One feeding a day
21. Difficult to troubleshoot
1. One opportunity per day
22. Difficult to accommodate last minute order
23. Risk of having acidity build up in the levain
1. Change in the final product characteristics
2. Not so good for flavor profile
24. Convenient feeding schedule
Two feeding a day
25. Convenient schedule
26. Good for consistency of the culture
27. Good for troubleshooting if necessary
28. Possibility to accommodate last minute order
29. More chances to increase or decrease quantity if necessary
Three feeding a day
30. Very good schedule for consistency
31. Easy to troubleshoot if necessary also easy to accommodate last minute order
32. Allow the baker to have levain ready to bake at least 3 times a day
33. Demanding feeding schedule
Maintening the culture
34. General considerations
1. Hygiene
2. "Contamination"
35. Feeding consistency
1. Water temperature
2. Proportion of the ingredients
3. Fermentation temperature
4. Type of flour
5. Timing
Factors affecting sourdough characteristics
36. Hydration
1. Affect type of acidity developed in the culture
2. Liquid
3. Stiff
37. Storage temperature
1. Ambient
2. Lower temperature
3. Retarding
38. Flour
    1. Type of flour
    2. Ash content
39. Proportion of starter
40. Feeding process
1. Number of feeding per day
41. Acidity level
In the final dough
42. Proportion of levain
1. Related to dough and bread characteristics, Strength and Flavor (acidity level)
43. Use for different types of product
1. Possibility to develop different cultures with different characteristics, Whole Wheat,
   Rye, Sweet dough
General consideration
44. Culture process can be designed to fit production and facility requirement
45. Consistency very important
46. One little change could affect the culture characteristics
47. Minor everyday changes could affect the final product characteristics
Sourdough baking process
48. Mixing
1. Short or improved mix
49. First fermentation
1. Longer
50. Dough handling
1. More gentle
51. Final proof
1. Longer
2. Easy to retard
52. Scoring
1. Very tolerant dough
53. Baking
1. Lower temperature when possible

Here are some images that graphically show how much of the process takes place.


The transformation made by the micro-organisms in the sourdough process


The Sourdough feeding process when the starter is taken from the final dough


The Sourdough feeding process when the starter is taken from the levain


Diagram of the sourdough process