The Potential Health Benefits of Phenolic Wine

Our progress is as follows:

  1. Establish the levels of resveratrol and other phenolics are present in commercial wines (where specific data is not available). Over 180 wines have been analyzed for both resveratrol and other phenolics by HPLC and this data is being compiled into a manuscript. The resveratrol levels were described in the mid-year report.
  2. Investigate plant levels of resveratrol where specific data is not available, (in collaboration with Andrew Walker) After a frustrating initial effort we have now developed a procedure to carry out this analysis. However, interest in resveratrol has waned due to the lack of any data demonstrating that is has much health impact, and we may not proceed with characterizing the levels in many grape samples. We have found a resveratrol derivative, piceid, previously unknown in grapes, and will look at a few wine samples for this compound to see if it is also present there.
  3. Assess the translocation of resveratrol in the grapevine and the prospect of controlling the levels of resveratrol in grapes, (in collaboration with Doug Adams) This goal was not met, and given the waning interest in resveratrol, will not now be attempted.
  4. Determine how the levels of resveratrol and other specific phenolics are affected by wine making treatments. This goal was partly met in a preliminary study and another project to be completed this summer will show how efficiently resveratrol is transferred from grape to wine in the fermentation process.
  5. Screen all phenolics in wine for potential anti-oxidative capacity. Determine how these materials could be isolated from grape waste material/pomace.(in collaboration with Frankel and Kinsella) The first part of this project is now nearly complete, and the second part, a rather significant undertaking, will be investigated next year in collaboration with an industry partner.
  6. Test the specific anti-oxidative potential of promising components from the screening using other tests that would be directly related to a health impact, (in collaboration with Frankel and others) This work is still in progress, but has been partly completed by analyzing the potency of known compounds from wine. That study is will be complete after one or two more compounds are tested after isolation from grape juice.