Sensory and chemical characteristics of trans-resveratrol-fortified wine

Abstract

Background and Aims: trans-Resveratrol (tR) is a grape-derived polyphenolic that is believed to confer considerable health benefits to humans. Its concentration in wine, however, is highly variable, and thus direct fortification of wine with tR has been proposed to create a high-value, health-promoting wine product. This study determines the sensory and chemical characteristics of tR fortified white and red wine. Methods and Results: Riesling and Cabernet Sauvignon wines were enriched with 20 mg/L and 200 mg/L tR. Basic chemical and sensory indicators of wine quality, trans- and cis-resveratrol concentrations, and antioxidant capacity were assessed at bottling and at 6, 18, 31, 44 and 58 weeks post-bottling. tR concentrations in bottled wine remained relatively stable throughout the 58-week period of this study. In addition, tR-enriched wines had a significantly higher antioxidant capacity compared with control wine, and Cabernet Sauvignon fortified at both tR concentrations had greater colour intensity. Basic chemical indicators of wine quality were not affected by tR fortification, and sensory changes were minimal, with higher bitterness intensity in Riesling fortified at 200 mg/L tR the most consistent finding. Conclusions: tR is relatively stable in wine during bottle aging, and tR enrichment up to 200 mg/L results in minimal change to wine quality, particularly with red wine. Significance of Study: This is the first study to investigate the chemical and sensory characteristics of tR-enriched wines. Results indicate that these products may have considerable potential for the functional food market.