Climate Effect on Morphological Traits and Polyphenolic Composition of Red Wine Grapes of Vitis vinifera

Wine quality is determined by the development of grape maturation, which is highly dependent on climate variations. Extreme weather events are becoming more common, which will affect the productivity and quality of grapes and wine. Grape development depends on many factors, including weather, and extreme events will influence berry size, skin thickness and the development of some key compounds, such as phenolics. In this work, the ripening evolution and phenolic content of Vitis vinifera extracts from a vineyard in Alentejo (Portugal) were evaluated in two distinct climatic years. During this period, the influence of climatic conditions on grape ripening, and thereby on red wine quality, was assessed. The results demonstrate differences in polyphenol compounds between years and the importance of monitoring their content during maturation. The reduction of berry size, apparently due to lower pluviosity and higher temperatures, resulted in a higher content of polyphenolic compounds related to grape quality.