|KENNEDY, JAMES - OREGON STATE UNIVERSITY
Submitted to: Northwest Center for Small Fruit Research Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 10/22/2007
Publication Date: 6/9/2008
Citation: Lee, J., Kennedy, J.A. 2008. Understanding micro-oxygenation technique and the oxidation of grape/wine polyphenolics. Year 1. Northwest Center for Small Fruit Research Proceedings. p.83.
Interpretive Summary: Wine tannins and color are important red wine quality factors that can be manipulated by grape growing and winemaking practices. Tannin quality in wine is a high-interest research topic. Tannins stabilize wine color, enhance mouthfeel, and can impart characteristics that enhance the quality perception of red wines. We seek to better understand tannin evolution in wine by developing and modifying analytical techniques (utilizing high performance liquid chromatography coupled with a diode array detector and mass spectrometer detection), and applying these techniques to wines produced by industry cooperators.
Technical Abstract: This study was initiated to understand the evolution of polyphenolics in red wine by monitoring wine polyphenolics with analytical methods that have been developed or modified by our laboratories. In conjunction with the industrial scale winemaking experiments, model wine oxidation experiments are being conducted concurrently. In August 2006, grapes (at optimum tannin extraction maturity) were harvested from the OSU experimental vineyard located in Alpine, Oregon. Proanthocyanidins were isolated and purified immediately from the collected grapes. Preliminary experiments have been conducted to identify the appropriate model wine system. Controlled oxidation reactions on these tannins are being conducted to provide insights into marker compounds to examine. These will reflect the extent of oxidation of polyphenolics in the commercial wines produced with and without micro-oxygenation. Also, wines with different ages were analyzed to fine-tune our tannin oxidation marker compound identification and method development.