However, for any home-brewed wine, in the fermentation process will produce trace formaldehyde, as long as the control of home-brewed wine fermentation conditions, pay attention to hygiene, do not infected with stray bacteria, the fermentation temperature between 28-35 degrees, do not contact iron, copper tools, avoid direct sunlight, fermented wine will not formaldehyde, methanol and other hazardous substances exceeded the standard.
Brewing skills: 1, the choice of grapes should be fresh, do not bring moldy grapes;
2, but also to disinfect the grapes to kill harmful bacteria, reduce the release of methanol in the fermentation process;
3, grapes should be dry before brewing, so that it is also in order to fermentation of the full and the taste of the wine is pure, so as to avoid the process of fermentation due to the grapes with water and produce methanol;
p> 4, the choice of winemaking appliances is also very important, to use wooden containers, never use plastic containers, plastic containers will produce more harmful substances in the winemaking process of methanol and other alcohols;
5, in the fermentation process as long as possible, that is, the wine should be aged.