Ask the Expert – Using Redox Potential with Dr. Gordon Walker


January 5, 2023    
1:00 pm

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Join our Expert Consultant Dr. Gordon Walker as he talks about using Redox Potential as a process parameter for winemaking. What is it? Why is it important? How to measure it? How our winemaking decision affect it.

The most common metrics for tracking wine fermentations are Brix (density) and Temperature (heat), however, neither of these parameters adequately describe yeast behavior in real time. Oxidation Reduction Potential (ORP) or Redox Potential is a dynamic measurement that can be used to track fermentations in real time. ORP is a composite measurement of dissolved oxygen, pH, temperature, and all the chemical half reactions in solution. The value of ORP is in providing a new process parameter that can be used to not just track yeast activity, but also be used to control fermentations stylistically. Implementation of ORP probes in the winemaking processes will result in faster and more robust fermentations, while giving winemakers a new way of visualizing what is happening in their tanks. There is also potential to use ORP as another method to control micro-oxygenation and other aspects of wine aging.

After Dr. Walker’s presentation, there will be a Q&A session.

More on Dr. Walker:

Dr. Gordon Walker is a PhD Biochemist with a passion for all things fungi and fermentation. At UC Davis he worked with Dr. Linda Bisson, where their research focused on interactions between yeast and bacteria in wine fermentations.  After finishing his doctorate, he worked at Opus One Winery, isolating wild yeast strains to enhance the microbial terroir and help pioneer the use of redox potential as a process parameter for winemaking. After spending time supporting Bay Area Biotech companies, he returned to UC Davis to complete a post-doc with Dr. Ron Runnebuam, where he continued his work on redox potential and helped to elucidate the chemical and biological contributions to terroir.