It is the ester precipitation of liquor during storage. Some wines need to be stored for several years after brewing. In this process, esterification will occur, resulting in a mixture of ethyl linoleate, ethyl oleate and ethyl palmitate.

When the temperature decreases, the solubility of these esters in wine decreases, and white crystals of saturated precipitation appear, forming precipitates.

It is also possible that the sediment is caused by humus in the water. Due to equipment or other reasons, some microorganisms will be inadvertently introduced in the brewing process of liquor, and microorganisms cannot survive in liquor. Bacteria don't rot after death, and these deposits will be produced when protein flows out.

It may be the precipitation caused by impure spices. Nowadays, many wines are flavored with essence. If the essence is impure, it will contain impurities. If these spices are used for seasoning, flaky or flocculent precipitation will occur.

Treatment of sediment in liquor;

Liquor has been turbid and precipitated. If it has not gone bad, it can be absorbed before drinking. Commonly used adsorbents include activated carbon, charcoal and activated clay. Adsorption and removal of substances causing turbidity and precipitation. That is, the adsorbent is put into the wine, stirred and then filtered.

The selection and dosage of adsorbent should be different according to the performance of adsorbent and the degree of turbidity and precipitation of liquor. The best way is to do a few experiments to get good results, and then do a lot of treatment.