Changes in the carbohydrate-acid and phenolic complexes of grapes in the dynamics of ripening

All-Russian National Research Institute of Viticulture and Winemaking Magarach of the RAS, 31 Kirova Str., 298600 Yalta, Republic of Crimea, Russian Federation

^* Corresponding author: cod7-4orever@mail.ru

Abstract

The primary challenge in red wine production is optimizing conditions for the accumulation of phenolic compounds in grape berries, crucial for the wine’s aroma, color, and flavor. With climate change impacting these components, it’s vital to study the transformation of carbohydrate-acid and phenolic complexes as grapes reach ripeness. This study focuses on the ‘Bastardo Magarachskiy’ grape variety and the effects of foliar mineral fertilization (NTP-Sintez LLC, Belarus) during ripening. Our findings show that experimental processing schemes enhance sugar accumulation in the berries by 1-4 g/100 cm³. The total anthocyanin potential ranged from 1187 to 1684 mg/dm³, with maximum extraction efficiency (61-65%) occurring at sugar concentrations of 21-23 g/100 cm³. Higher sugar levels led to reduced extraction efficiency. The phenolic profile was dominated by flavan-3-ols and anthocyanins, comprising 82.7% to 96.3% of total phenolics. Throughout ripening, there was a significant increase in the mass concentration of primary phenolic compounds in the berries, highlighting the importance of monitoring these changes for optimal wine production.