Micro 2100

Wild Yeast: Isolation to Fermentation

Credit Hour(s): 3 Units
Instructor(s): Carlson
Offered: Autumn, Spring, Summer (if high demand)
Prerequisite(s): Biology 1110 or 1113; Chemistry 1110 or 1210 or 1610 or equivalent
Role in Microbiology Major: Group 1 Elective

Learning Topics:

  • Basic yeast biology
  • Introduction to domesticated (Saccharomyces species) and wild (non-Saccharomyces species) yeast strains used in the brewing industry.
  • Enrichment and purification culturing techniques used to isolate yeast from the environment
  • Viable cell enumeration using hemocytometers and viable plate counts
  • Yeast growth modes including aerobic respiration and ethanolic fermentation.
  • Manipulation of fermentation conditions (sugar utilization, sugar concentration, pH, ethanol percent)
  • Genomic DNA isolation, PCR, and gel electrophoresis
  • ITS sequencing for yeast species identification
  • All-grain brewing process to create hopped wort
  • Bacterial contamination identification and control
  • Beer analysis (pH, specific gravity, microbiological, sensory, percent ethanol)

Learning Objectives:

Successful students will be able to...

  1. Properly prepare and view microbial specimens for examination using microscopy (bright field and phase contrast).
  2. Use pure culture and aseptic technique to identify, manipulate, and transfer both yeast and bacteria specific to the brewing industry.
  3. Make liquid and solid microbial growth media.
  4. Use appropriate microbiological, molecular, and brewing lab equipment/methods including micropipettes, spectrophotometers, microscopes, densitometers, hydrometers, hemocytometers, and differential media.
  5. Practice safe microbiology using appropriate protective and emergency procedures.
  6. Use molecular biology techniques to isolate genomic DNA, perform ITS region-specific PCR amplification, and purify PCR DNA products.
  7. Submit DNA products for Sanger sequencing and use the results to bioinformatically determine yeast species.
  8. Apply the “brew-in-a-bag” all-grain brewing technique to create a small batch of wort.
  9. Properly enumerate yeast starter cultures and calculate the appropriate pitching rate for ethanolic fermentation.
  10. Document and report on experimental protocols, results and conclusions.
  11. Understand how yeast participate and influence the creation of a particular beer style.
  12. Understand how humans utilize and harness microorganisms and their products in the brewing industry.
  13. Communicate and collaborate with others in written and oral formats.