Jan Rescic1, Maja Mikulic-Petkovsek2, Denis Rusjan2. 1. Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana, Slovenia. jan.rescic@bf.uni-lj.si. 2. Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana, Slovenia.
Abstract
BACKGROUND: The interest in producing wines preferred by consumers increases the need for improving practices to modify grape and wine composition. The aim of this study was to assess the impacts of three different canopy management measures, (1) early leaf removal in the cluster zone, (2) removal of young leaves above the second pair of wires and (3) Double Maturation Raisonnée, on the yield and chemical composition of 'Istrian Malvasia' grape and wine. RESULTS: Double Maturation Raisonnée had a significantly greater impact on phenolic compounds, while the highest soluble solids (24.3 and 23.5 °Brix) and titratable acidity (7.0 and 7.1 g L-1 ) were measured at early leaf removal. Leaf removal at véraison caused an unexpected augmentation of flavonols in the berry skin. Early leaf removal resulted in significantly lower extracts of wine. Nevertheless, they reached the highest mark (16.5 out of 20.0 points) in sensory evaluation compared with leaf removal at véraison and Double Maturation Raisonnée (15.0 points) and control (16.0 points). CONCLUSION: Leaf removal at véraison and Double Maturation Raisonnée improved the phenolic composition of wine, producing a full-bodied wine. On the other hand, early leaf removal significantly augmented the yield and titratable acidity, hydroxycinnamic acids and flavanols of wine, which might have led to a fresher but less-bodied wine.
BACKGROUND: The interest in producing wines preferred by consumers increases the need for improving practices to modify grape and wine composition. The aim of this study was to assess the impacts of three different canopy management measures, (1) early leaf removal in the cluster zone, (2) removal of young leaves above the second pair of wires and (3) Double Maturation Raisonnée, on the yield and chemical composition of 'Istrian Malvasia' grape and wine. RESULTS: Double Maturation Raisonnée had a significantly greater impact on phenolic compounds, while the highest soluble solids (24.3 and 23.5 °Brix) and titratable acidity (7.0 and 7.1 g L-1 ) were measured at early leaf removal. Leaf removal at véraison caused an unexpected augmentation of flavonols in the berry skin. Early leaf removal resulted in significantly lower extracts of wine. Nevertheless, they reached the highest mark (16.5 out of 20.0 points) in sensory evaluation compared with leaf removal at véraison and Double Maturation Raisonnée (15.0 points) and control (16.0 points). CONCLUSION: Leaf removal at véraison and Double Maturation Raisonnée improved the phenolic composition of wine, producing a full-bodied wine. On the other hand, early leaf removal significantly augmented the yield and titratable acidity, hydroxycinnamic acids and flavanols of wine, which might have led to a fresher but less-bodied wine.