Impact of Vine Deficit Irrigation on Wine Quality Parameters

This study evaluated the impact of conservative irrigation management on premium wine quality by relating quantitative results on tannin development in the vineyard to the perception of astringency in experimental wines from deficit-irrigated fruit. On a per berry basis, the skin tannins increase slightly between veraison and harvest. There is a trend that the deficit-irrigated treatments are in general higher in tannins than the fully irrigated treatment. In the seeds, the tannins decrease between veraison and harvest. There were no statistically significant differences in primary amino nitrogen for all treatments on a per berry basis. A sensory evaluation of the 1998 wines revealed significant differences between all treatments in flavor by mouth. A correlation of the sensory results with the analytical data is in progress.