The Extraction of Condensed Tannins in Red Wine Production

The winemaking portion of the experiment was completed on time on the commercial scale and on the small scale at UCD. Samples were collected and prepared for analysis. The various chemical analyses are still underway due to the large number of samples and the demand for analysis equipment by other projects. In summary, approximately 300 samples have been analyzed to date, all for phenolics by normal and reverse phase HPLC, as well as spectral measures of co-pigmentation. These have included all samples from the commercial wines, but not those from the small scale analyses. Since each of those procedures yields many results, the challenge now is to try an interpret the data to the point where it can be summarized in simple and understandable terms. Data collected so far shows some expected trends, but also some unexpected ones, in particular the increase in tannin levels during aging. With the large amount of data collected, additional analysis is needed to look for interactions and consistency. Additional data still must be collected and analyzed on the small scale wines. This data will be used to plan for the third year’s experiments during summer 1999.