Brettanomyces Dissertation

Pure Culture Fermentation Characteristics of Brettanomyces Yeast Species and Their Use in the Brewing Industry

List of Tables and Figures

Tables

  • 1. Ability of five Brettanomyces strains to culture on various media agar
  • 2. Morphological characteristics observed in five Brettanomyces strains
  • 3. Volatile compounds produced during semi-aerobic batch culture
  • 4. Volatile compounds produced from fermentations with multiple pitching rates
  • 5. Fermentation performance with five initial concentrations of lactic acid present pre-fermentation
  • Figures

  • 1. Growth curve for five strains of Brettanomyces during semi-aerobic batch culture
  • 2. Growth curve comparison between MYPG substrate and wort substrate
  • 3. Cell viability comparison between MYPG substrate and wort substrate
  • 4. Mean fermentable sugars present after batch culture propagation
  • 5. Apparent attenuation with a pitching rate of 12×106 cells/ml
  • 6. Correlation between apparent attenuation and final pH with a pitching rate of 12×106 cells/ml
  • 7. Mean fermentable sugars present after primary fermentation with a pitching rate of 12×106 cells/ml
  • 8. Mean ethyl acetate and ethyl lactate formed with a pitching rate of 12×106 cells/ml
  • 9. Mean ester compounds formed with a pitching rate of 12×106 cells/ml
  • 10. Mean higher alcohol compounds formed with a pitching rate of 12×106 cells/ml
  • 11. Mean vinyl phenols formed with a pitching rate of 12×106 cells/ml
  • 12. Mean vicinal diketones formed with a pitching rate of 12×106 cells/ml
  • 13. Impact of pitching rate on apparent attenuation
  • 14. Mean fermentable sugars present after fermentations with multiple pitching rates
  • 15. Mean ethyl lactate formed with initial lactic acid concentrations of 0, 100, 500, 1,000, 3,000 mg/l
  • 16. Mean ethyl acetate formed with initial lactic acid concentrations of 0, 100, 500, 1,000, 3,000 mg/l
  • 17. Mean ethyl caproate formed with initial lactic acid concentrations of 0, 100, 500, 1,000, 3,000 mg/l
  • 18. Mean ethyl caprylate formed with initial lactic acid concentrations of 0, 100, 500, 1,000, 3,000 mg/l
  • 19. Mean 4-vinylguaiacol formed with initial lactic acid concentrations of 0, 100, 500, 1,000, 3,000 mg/l

Acknowledgments

I would like to thank Paul Cyphus for his dedication throughout the research and quality help in the lab, Graham McKernan for help in the pilot brewery, and James MacKinlay for running analysis on the many samples. I would also like to thanks my supervisors Professor David Quain and Dr. Anne Hill for their input throughout this project. Finally I would like to thank Lauren Salazar of New Belgium Brewing Company, Vinnie Cilurzo of Russian River Brewing Company, and Andy Parker and Matt Thrall of Avery Brewing Company for their gracious time, conversations concerning their work conducted with Brettanomyces, and the detail in which they bestowed upon me their experiences with this funky yeast.