Study of Lignans in Wine Originating from Different Types of Oak Barrels

This study aimed to determine the concentrations of the lignans pinoresinol, secoisolariciresinol, matairesinol and isolariciresinol in white wines aged in twelve different oak barrels originating from different cooperages and regions and with different toasting levels. In a two-year experiment the influence of oak barrels and of variety on lignan content was monitored. The results of this study show that the use of oak barrels affects only syringaresinol concentrations. Wines from low-releasing barrels contained mean concentrations of 20-50 ng/ml of syringaresinol, while wines from high-releasing barrels contained mean concentrations of 140-160 ng/ml of syringaresinol. Wines from the other barrels contained mean concentrations of 70-100 ng/ml of syringaresinol. The amounts of matairesinol and pinoresinol were affected by grapevine cultivar. In Veltliner Grün, the mean matairesinol concentration was significantly higher than in all other cultivars except for Chardonnay (mean concentrations 11, 6 and 3-5 ng/ml in Veltliner Grün, Chardonnay and other cultivars respectively). The amounts of isolariciresinol and secoisolariciresinol and total amount of lignan aglycones were affected by the interaction of cultivar and year. The mean concentrations of both lignans and total aglycone were significantly higher in Chardonnay from 2017 (210, 120 and 460 ng/ml for isolariciresinol, secoisolariciresinol and total aglycones respectively) than in all the other samples (60-130, 0-50 and 180-280 ng/ml for isolariciresinol, secoisolariciresinol and total aglycones respectively).