Methanol contents of Turkish varietal wines and effect of processing

Methanol levels of Turkish varietal wines obtained from different representative viticultural regions were determined and the effect of maceration time and pectolytic enzyme treatments on the methanol levels of the red wines were investigated. 164 wine samples (60 white, 4 rosé, 100 red) were analysed by gas chromatography–flame ionisation detector (GC–FID). Methanol levels ranged from 30.5 to 121.4 mg/l in white wines, 62.5 to 84.6 mg/l in rosé, and 61.0 to 207.0 mg/l in red wines. The highest level was found in Sultaniye among the white wines, and in Öküzgözü among the red wines. Methanol content of red wines increased with maceration time. Pectolytic enzyme treatments produced significantly higher methanol levels than the control wine. All the results show that methanol levels of Turkish wines are under the maximum acceptable limits of International Office of Vine and Wine (OIV) and do not represent a risk to consumer health.