The influence of different maceration techniques on the phenolic compounds and color parameters of red grapes Fetească neagră variety

Abstract

The investigation of various technological parameters affecting the extraction of the valuable compounds from the Fetească neagră variety of red grapes was performed. In particular, the impact of various maceration techniques on phenolic composition, color indicators, and biological potential expressed as antioxidant activity was evaluated. The grapes were manually processed and then subjected to different types of processing: low temperature maceration at 4°C (V1), conventional maceration at 25°C (V2), thermomaceration at 70°C (V3), and ultrasound-assisted maceration at different temperature values, such as: 5-10°C (V41), 30°C (V42) and 60-65°C (V43) with the same duration of 30 minutes. The evolution of the physico-chemical parameters of the samples was monitored at different time intervals of 2, 4, and 6 days, depending on the maceration type. The results revealed the higher impact of the temperature on polyphenolic compounds extraction from grape skins in the must, as well as for the compounds related to color of red wines.