Effects of different fermentation and storage conditions on methanol content in Chinese spine grape (<i>Vitis davidii</i> Foex) wine

The methanol content is an important indicator in determining the quality of wine. The effects of material quality, fermentation conditions and storage containers on the formation of methanol and other substances in winemaking process were studied. The methanol content in spine grape wine was observed to increase as the fermentation temperature increased. Extending maceration time and the increasing addition of pectinase also increased the methanol content. No significant change in methanol content was observed with various yeasts added. The methanol content in wine that is stored in oak barrels was the lowest compared to that in other containers. The optimal conditions to control the methanol content in spine grape wine should be as follows: ferment wine with high-quality materials under 25–26°C for 3–6 d, with a pectinase of 15–20 mg/L and yeast added; and store the wine in oak barrels.