Effect of Vegetation Time and Climatic Conditions on trans- Resveratrol Concentrations in Cabernet Sauvignon and Merlot Wines from Different Regions in Turkey

In this study, 21 wine samples obtained from wine manufacturers in Turkey and produced from differentgrape varieties cultivated in different geographical regions, were analysed to determine their resveratrolconcentrations. The HPLC method was used to analyse the trans-resveratrol concentrations of wines.Statistical analysis was done using IBM SPSS Statistics Version 20.0.0. Mean values were comparedby using the Tukey test at a confidence level of p = 0.05. The resveratrol concentrations of CabernetSauvignon and Merlot grapes were also determined. Since these two varieties are grown widely in manyregions of Turkey, they were studied in terms of the relationship of the resveratrol concentrations withparameters such as time of vegetation, total effective temperature, sunshine duration and rainfall. Positivecorrelations were observed between resveratrol levels and grape varieties, geographical regions and totaleffective temperature. The results of the statistical analysis showed that resveratrol concentrations alsovaried depending on vegetation time, sunshine duration and amount of rainfall in the vineyards. Thisstudy aimed to identify the relationships between (1) resveratrol concentrations of wines, (2) vegetationtime of the grapes and (3) climatic conditions of the respective regions. Moreover, the effects of grapetypes on resveratrol concentrations were investigated. This study contributes to the body of knowledgeby providing results on the utilisation of grapes that have high resveratrol levels for producing wines thathave functional properties that are increasingly in demand by consumers