Assay of the phenolic profile of merlot wines from Macedonia: Effect of maceration time, storage, SO<sub>2</sub> and temperature of storage

Abstract

Spectrophotometric assays of total anthocyanins, total phenolics, total catechins, total flavonoids, color intesity and hue were performed on Merlot wines obtained with 3, 6 and 10 days of maceration, containing 30 and 70 ppm SO2. Changes of phenolic contents were observed during three stages of the wines: after maceration, after 6 and 16 months in order to check the effect of maceration time, SO2 and storage of the wines. Wines were stored at low and higher temperature to check also the influence of storage temperature on the studied parameters. It was found that maceration time influences the content of polyphenol compounds, observing increasing of their concentrations with increased maceration time, while lower contents were measured in the wines after 16 months of storage (3006, 1732 and 1602 mg/l total phenolics and 478, 188 and 98.5 mg/l total anthocyanins, after maceration, after 6 and 16 months of storage, respectively, in wine with 30 ppm SO2). SO2 had not a significant effect, whereas higher temperature caused slight changes of polyphenols contents.