1, methanol: methanol is a toxic chemical, excessive intake will cause serious harm to human health. Excessive intake of methanol can cause central nervous system depression, impaired vision and other organ dysfunction.

2, heavy metals: home-made white face to face with all kinds of materials such as copper pots, galvanized pipe and other equipment used can not guarantee its safety, the material contains a small but still risky orders of magnitude of the metal elements iron, copper and zinc. Long-term exposure to the elements can accumulate inside the body and lead to chronic poisoning, causing damage to organs such as the liver, kidneys and central nervous system.

3, heterohydric alcohol oil: heterohydric alcohol oil is an important component of white wine, the right amount of heterohydric alcohol oil can give white wine a unique flavor. Improper handling or storage process leads to excessive heterohydric alcohol oil content, making white produce bitter taste or odor. The off-flavor comes from the presence of mold, continued fermentation, or other contaminants, and is a potential risk to human health.