Effects of Sunlight Exposure on Berry and Wine Monoterpenes and Sensory Characteristics of Traminette

Abstract

Traminette is a cold-hardy interspecific Gewürztraminer hybrid winegrape cultivar grown in the eastern United States. A study from 2003 through 2005 investigated impacts of canopy management on aromatic qualities of fruit and wine. Cluster-shading treatments under leaf layers (0, 1, 2, and >3) and synthetic coverings (greenhouse shade cloth and light-excluding apple bags) were implemented in field trials, and fruit composition and wine sensory analyses were conducted. Fruit from fully exposed clusters had 30% higher concentrations of potentially volatile terpenes compared with heavily shaded fruit (>3 leaf layers). Descriptive analyses showed higher ratings for color, linalool, rose, and spice aromas with exposed wines in 2004. There were no differences in wine aroma intensities in 2005. Berry skin color at harvest correlated with potentially volatile terpenes concentration and may be used as a field guide to estimate monoterpene concentration at harvest.