Influence of berry size on red wine colour and composition

Abstract

Background and Aims According to one of the classical postulates of viticulture, cultivars with smaller berries produce the best red wines. During grape development, some differences at berry level lead to a wide range of fruit heterogeneity at harvest. One source of heterogeneity at harvest is berry size. The aim of this work is to determine if berry size affects the colour and chemical composition of wine. Methods and Results Cabernet Sauvignon grapes were harvested at optimal ripeness, and screened by two sieves, to select three groups of grapes of large, medium and small size. Wines were made from each size class in triplicate, with the control being wine made from unselected grapes. The colour properties and composition of the phenolic substances of the wines were determined. Conclusions Wine colour showed the clearest trend in this experiment: the smaller the berries, the deeper the wine colour, as measured by the CIELab coordinates as well as by (wine) colour intensity. Moreover, stilbene concentration increased when berry size decreased, while pH did the opposite. Finally, wines made from small berries had a titratable acidity, total phenolic index and monomeric flavan-3-ol concentration higher than that of wines made from the large- and medium-sized berry sizes. Significance of the Study These data suggest that berry size classification in wineries would be an interesting tool for management of wine composition.