Non-traditional grape variety for elaboration of sparkling wines: phenolic evolution during aging on lees

Abstract

The use of non-traditional grape varieties for elaboration of sparkling wines is a challenge for the winemaking industry. The Goethe variety stands out as being a typical cultivar of the Urussanga Region in the south of Santa Catarina State, Brazil, where most of its production is directed to the elaboration of still wines. The objective of this work was to characterize the base wine and sparkling wines (cv. Goethe) regarding classical oenological parameters and evaluate the influence of aging on lees of sparkling wines in the evolution of phenolic compounds, antioxidant activity in vitro and browning index. The samples were analyzed relating the oenological parameters and monitored for 15 months of aging on lees to verify the evolution of total and individual phenolic compounds (hydroxycinnamic acids). The results showed that during aging on lees, the sparkling wines had an increase in antioxidant activity in vitro. As for total phenolics, there was a decrease in concentrations after 15 months of aging. Among the hydroxycinnamic acids, trans-caftaric acid was the most abundant. During the aging the concentration of caffeic acid increased in the sparkling wines (0.91 mg L^-1) in relation to the base wine (0.41 mg L^-1), and by correlation analysis it was possible to observe a strong correlation (r=0.90) between this compound and  the antioxidant activity. These results demonstrated the great potential of using the Goethe variety for the elaboration of sparkling wines.