Maturation of Agiorgitiko (Vitis vinifera) red wine on its wine lees: Impact on its phenolic composition
Abstract
Maturation of wine on lees (often referred as sur lie) is a common practice applied by many winemakers around the world. In the past this method was applied mainly on white and/or sparkling wine production but recently also to red wine production. In our experiment, we matured red wine on wine lees of two origins: a) Light wine lees, collected after the completion of the alcoholic fermentation, b) Heavy lees, collected after the completion of the malolactic fermentation. The lees were free of off-odors and were added in the red wine in percentage 3% and 8%, simulating common winemaking addition. The maturation lasted in total six months and samples were collected for analysis after one, three and six months. During storage the lees were stirred. Control sample contained no wine lees and was not stirred. At the time intervals, the individual anthocyanin concentration, colour parameters, total phenolic and tannin content, and antioxidant activity were measured. It was also determined the mean degree of polymerization of flavan-3-ols (mDP), since it has been shown that it is strongly related to the perceived astringency of the wine. The results showed that addition of wine lees may not be beneficial for the wine quality. There was no change in color parameters, and polyphenolic content among the control and the treatments. Furthermore, mDP, was not affected among treatments suggesting that perceived astringency and bitterness may not be affected. These findings were observed in all treatments independent of the amount of lees added and/or the origin of the wine lees (light or heavy lees). As a result it is suggested that the method of maturation of red wine on its lees should be reconsider as a method to improve the quality of the wine, since there was not observed any positive impact on the analytical parameters measured.
Issue: Macrowine 2016
Type: Poster
Authors
*Agricultural University of Athens