Influence of UV and ozonised water treatment on trans-resveratrol content in berry skins and juices of Franc and Green Veltliner grapes

Abstract

Grapes from two varieties - Franc (red) and Green Veltliner (white) were processed using UV radiation at selected powers and times. Irradiated grapes were stored for 24, 48, and 72 h at room temperature. A second set of grapes was dipped into ozonised water. We tested the influence of ozone concentration, dipping time, and storage time. All experiments were performed using grapes harvested in 2009, 2010, and 2011. The two treatments were compared relative to trans-resveratrol content in grape skins and juices (prepared from treated grapes).

Keywords

• grape juices
• stilbens content
• uv irradiation
• ozonisation