Aldehyde in liquor is an oxide of alcohol with corresponding molecular size, which will also be produced during liquor fermentation. Low-boiling aldehydes include formaldehyde and acetaldehyde, while high-boiling aldehydes include furfural, butyraldehyde, valeraldehyde and hexanal. Aldehydes are more toxic than alcohols, among which formaldehyde is the most toxic, about 30 times more toxic than methanol. It is protoplasmic toxin, which can coagulate protein, and 10g formaldehyde can kill people. In the case of acute poisoning, cough, chest pain, burning sensation, dizziness, unconsciousness and vomiting may occur.
Furfural is also harmful to health. When rice husk, corncob and bran are used as auxiliary materials, the content of aldehydes such as furfural in distilled liquor is high.
In order to reduce the aldehyde content in liquor production, rice bran, rice husk or cooking accessories in advance should be used less. When steaming wine, the temperature of flowing wine should be strictly controlled, and the total aldehyde content in wine should be reduced.