Technological characteristic, aromatic profile and biological potential of wines from the local white wine variety Kokorko

Tatyana Yoncheva, Dimitar Dimitrov, Lambrin Topuzliev, Dimitar Dimov

Abstract: A study of the technological characteristic of Kokorko white wines was carried out. The object of the study were wines from two consecutive vintages (2019 and 2020), obtained from two growing regions. They were produced in the Experimental Wine Cellar of Agricultural University (AU) – Plovdiv (2019 and 2020), and the Yalovo Winery – Veliko Tarnovo (2019). The laboratory analyzes were performed at the Institute of Viticulture and Enology – Pleven. The results showed that the samples from AU – Plovdiv had higher alcohol content, total and sugar-free extract. The determined low titratable acidity was typical for the variety. A correlation was found between the content of the analyzed phenolic compounds and the antioxidant activity of the wines. Their amounts increased in the order: Kokorko, 2019 (Yalovo Winery) < Kokorko, 2020 (AU – Plovdiv) < Kokorko, 2019 (AU–Plovdiv). A diverse volatile composition was identified in the studied wines, consisting of 17 compounds (1 aldehyde, 4 higher alcohols, 8 esters, 3 terpenes and methyl alcohol). The wine from the Yalovo Winery had the highest total volatile content. The highest total concentration of higher alcohols was found in the sample, 2020 vintage. The main identified representatives were 2-methyl-1-butanol, 3-methyl-1-butanol, 1-propanol and 1-butanol. The wine from the Yalovo Winery contained the most acetaldehyde and a total amount of esters. The least esters were found in Kokorko, 2020 vintage. The main representatives of the ester fraction identified in all wines were ethyl acetate and isopropyl acetate. Propyl acetate, isopropyl acetate, butyl acetate and isobutyl acetate were also identified. The terpenes α-terpineol, nerol and geraniol were found, as the latter had the highest content. Methyl alcohol was present in all wines in quantities that meet the safety criteria of the drink. Kokorko wines, made in AU – Plovdiv, had better organoleptic features in terms of aromatic and taste properties.

Keywords: antioxidant activity; chemical composition; Kokorko variety; organoleptic profile; phenolic compounds; volatile components; white wine

Date published: 2023-10-23