Effects of Different Crop Load of Vine and Length of Maceration on Polyphenolic Content of Vranac Cultivar

Abstract

Polyphenols have a significant impact on the quality of the red wine grape varieties. Certain amphelotechnical measures and technological pro­cesses affect directly the content of polyphenols in grapes and wine. The aim of the study was to investigate the influence of different crop load of the vine and length of maceration of grape pomace on polyphenolic content and sensory properties of Vranac cultivar which represents the leading red variety in the Republic of Macedonia. Studied the different crop load of the vine (control, variant 1 with a 25% reduction of the yield, variant 2 - 35% reduction of the yield and a variant of 3- 50% reduction of the yield) as well as different times of maceration (7days and 14 days) on the phenolic composition of wine. Test results showed a positive correlation between the crop load and the content of total polyphenols, ie, reducing the number of bunches per vine comes to an increase in the content of total polyphenols in wine as well as length of maceration achieves the same correlation.