The Effects of Sun Exposure on the Phenolic Content of Cabernet Sauvignon Berries During Development

Abstract

The phenolic composition of Cabernet Sauvignon grape berries was monitored throughout the growing season from anthesis to maturity in clusters exposed to sunlight and clusters growing in natural canopy shade. Analyses included total soluble phenols, anthocyanins, and polymerized phenols. Significant differences were found between sun-exposed and shaded fruit in soluble phenol content per berry and in both anthocyanin concentration and total content per berry preharvest. There were no significant differences at harvest, however. Total soluble phenols increased until véraison, then decreased from véraison to harvest. The percentage of polymerized phenols decreased during early berry growth, then increased from véraison to harvest.