The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Outline of the Sourdough process

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Outline of the Sourdough process

The feeding chart

    History of sourdough

  • Chronology
    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
  • First sourdough studies remained very basic, until the discovery of the microscope
  • Dr. Kline and Dr. Sugihara did some extensive researches on sourdough in 1971
  • Nowadays, scientists are able to isolate the micro-organism contained in the culture
  • Because of the very complex environment, some reactions happening in sourdough remains still difficult to explain
  • Different perceptions of the word "sour" in different country (souertaig, levain)
  • There are still a lot of myths surrounding sourdough bread process
  • Flour and water are the main ingredients
  • The way we work with them will affect the characteristics of the final product
  • Need to perpetuate the culture day after day
  • Very demanding process
  • Consistency is very important
  • Understanding sourdough process

      General concept

  • Start with natural ingredients
  • Develop a culture of micro-organism able to generate fermentation
  • Perpetuate the culture
    • How to start a sourdough culture

  • Different methods
    1. Different ingredients
    2. Different consistency of the culture
  • One natural process
  • Provide vital conditions to the micro-organism
    1. Nutrients
    2. Water
    3. Oxygen
  • Demystifying the myth
    • Factors affecting the elaboration

  • Type of flour
  • Hydration
  • Amount of nutrients
  • Temperature
  • Location
    • Bacteriological changes happening during the culture elaboration

  • Natural selection of the microorganism
    1. Yeast
    2. Bacteria
  • Made by the ability of the microorganism to live in this new and specific environment
    1. Acidity
    2. Lack of oxygen
    3. Type of nutrients
  • Reproduction of the microorganism
    1. Population of microorganism starts to grow
  • Natural balance in the flora
    1. Between yeast and bacteria
  • Beginning of the fermentation process
    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