The objective of this work was to evaluate the phenolic composition
of wine from 'Cabernet Sauvignon' (Vitis vinifera) grapes subjected to leaf
removal management at different timing, in a high-altitude region. The
experiment was carried out in the 2015 and 2016 vintages, in a vineyard located
in the municipality of São Joaquim, in the state of Santa Catarina, Brazil.
The treatments consisted of different periods of leaf removal in the clusters,
at five phenological stages ‒ full bloom, buckshot berries, pea-sized berries,
veraison, and 15 days after veraison ‒, and of a control without leaf removal. At
harvest, 50 kg of each treatment were collected for winemaking. The contents
of gallic acid, catechin, p-coumaric acid, vanillic acid, resveratrol, quercetin,
rutin, and kaempferol were evaluated. The results showed the importance of
leaf removal before veraison, to obtain wine with a higher concentration of
phenolic compounds, which favors wine quality. The leaf removal management
promotes the increase of gallic acid, vanillic acid, p-coumaric acid, resveratrol,
quercetin, and kaempferol in wine. The early leaf removal before veraison
results in increases in vanillic acid, p-coumaric acid, resveratrol, quercetin, and
kaempferol. The wine made from grapes not subjected to leaf removal shows
higher values of catechin and rutin