CHARACTERIZATION THE INFLUENCE OF THE ROOTSTOCKS SO4, 44-53M, 110R AND FERCAL ON THE VOLATILE COMPOSITION OF RED WINES FROM THE HYBRID VARIETIES STORGOZIA (THREE HARVESTS) AND RUBIN (TWO HARVESTS) IN THE CONDITIONS OF CENTRAL NORTHERN BULGARIA

Abstract

A gas chromatographic (GC-FID) study to characterize the influence of SO4, 44-53M, 110R and Fercal rootstocks on the volatile composition of red wines from the hybrid varieties Storgozia (harvests: 2017, 2018 and 2019) and Rubin (harvests: 2017 and 2019) under the soil and climatic conditions of Central Northern Bulgaria was conducted. The 110R rootstock in Storgozia has been shown to generate the highest total volatile content (756.10 mg/dm³) in 2017 harvest. 110R also affected the higher alcohols content of Storgozia. It generated the highest content of this indicator (713.00 mg/dm³) again in wines from the 2017 harvest. Regarding the content of esters, aldehydes and terpenes no significant differences were observed between the experimental variants of wines from this grapevine variety. In the case of Rubin wines, a very high final total volatile content was proved at rootstock 44-53M (1717.24 mg/dm³), harvest 2019. The highest concentration of higher alcohols in the 2017 harvest was identified for SO4, while in Rubin - the 2019 harvest, 110R generated the highest presence of higher alcohols. This fraction in both harvests was mainly represented by 2-methyl-1-butanol and 3-methyl-1-butanol. The esters were dominated by ethyl acetate and propyl acetate. In both harvests, the highest total terpene content was found in the wines from SO4 rootstock. The conducted research was evidence of the significant influence of different rootstocks on the volatile composition of wines from hybrid grapevine varieties in the conditions of Central Northern Bulgaria.