O2 Appetite (Nomasense DO rate of oxygen consumption)
Purchase O2 Appetite analysis, $100 per single sample.
Submissions of 12 samples, $720 (40% discount).
Research Kit for Phenolic Oxygen Uptake Capacity study (Warburg Flask Analysis)
In 1933, Jean-Michel Ribereau-Gayon’s doctorale dissertation related a method for assaying reductive potential in wine. Although researched at length by Dr. Vernon Singleton at U.C. Davis, the method never caught on.
Today, the perfect storm of winegrowing improvements aimed at tannin concentration, proper ripeness, increasing use of covercrops and the growing popularity of the near-hermetic Stelvin closure, all of which, while promoting quality and longevity, are suspected to be involved in increasing reduction, necessitating extended barrel ageing and/or oxygenation.
Recent studies have revealed that a red wine’s rate of oxygen uptake varies as much as 100-fold during its lifetime. A wine’s appetite for oxygen is thus a critical piece of information which informs decisions at all phases of its production, allowing us to assess its fragility during processing, requirement for barrel time, and readiness for bottling and longevity. The measure can also give us valuable feedback on the impact of site, viticultural practices, harvest maturity, extraction procedures, fining practices and blending options.
For a more in-depth discussion, read my Practical Winery and Vineyard article from January 2010
In response to this article, Nicolas Cantacuzene and John Ritchie of Emeritus Vineyards experimented with a prototypical apparatus which utilized the principles of Ribereau-Gayon’s method with a low cost prototype apparatus which did not employ a mercury manometer, obtaining interesting results. Please view the protocol and their videos explaining their procedure (part 1 part 2).
In February of 2011, I approached Nick Wolfe and Monique Perez Goff of the Methods and Analysis Committee of the guerilla research society, California Enological Research Association (CERA) who agreed to participate in a collaborative study to investigate the method. Dr. James Kennedy, renowned phenolic chemist and Chairman of the Dept of Viticulture and Enology at CSU Fresno, and Dr. Bruce Zoecklien of Virginia Polytech and co-author of Wine Production Analysis have also joined the study.
Goals of the study are:
-Investigation of best practices and equipment design optimization
-use the prototype method to survey the range of oxygen uptake potential among varietals, vineyard sites, vinification practices and during ageing for a wide variety of wine types.
-To determine the efficacy of the method for other suspected sources of reduction such as lees contact and minerality.
The protocol includes instructions on how the required equipment can be purchased and assembled by the user. WineSmith Consulting is also assembling kits of four flasks and reagents at $250.00 plus shipping as a convenience. Gallic acid standard is not included in the kit.