Behavior of phenolic and color parameters during grape vinificationof tannat and cabernet sauvignon cvs. in bagé-rs

The Tannat grape provides wines with good structure and coloration due to high concentration of phenolic compounds (Echeverry et al., 2005; Gonzáles-Neves et al., 2006; 2004a, b, 2002). The Cabernet Sauvignon cultivar yields a dark red wine, full-bodied, with a lasting pleasant odor (Camargo,1994; Souza, 2000).Through the monitoring of winemaking, it can be identified the behavior of phenolic compounds and color parameters in order to define the best and most suitable winemaking system, keeping the characteristics of interest. The study was conducted from a seven years old vineyard, located in the city of Bagé, Campanharegion of the RS state, Brazil, during the growing season of 2007, with Tannat and Cabernet Sauvignon cultivars. Vineyard- the vineyard was established from grafted plants in 1103 Paulsen rootstock, with spacing of 1.2 m between plants and 3 m between rows, in the simple espalier conduction system, and double Guyot pruning for Tannat cv. and simple cordon spur pruning for Cabernet Sauvignon cv. Microvinification - It was carried out the vinification of Tannat and Cabernet Sauvignon grapes harvested at technological maturity stage (March, 11th) based on the Classic method. For each experimental unit (bottle of 20 L) of each treatment, the grapes were crushed and desençada, and immediately added SO2 (50mg.L-1) and yeast (20mg.L-1 de Saccharomyces cerevisiae, Maurivin® brand), followed by 6 days of maceration at temperature of 20ºC to23ºC with daily reassembly, and cap removal on the day 7. This paper has allowed us to verify the behavior of compounds responsible for the color in winemaking of Tannat and Cabernet Sauvignon cv. wines. The decrease in acidity may have caused the fall of anthocyanin and polyphenolic compounds during the vinification for both varieties. However, Tannat cv., when compared to Cabernet Sauvignon cv., presented higher levels of these compounds. The results are very relevant because they allow the selection of the most suitable wine-making system for the studied cultivars, and also provide important information about their behavior in the studied counties.