Pectinase is refined by the fermentation of Aspergillus niger. It refers to a complex enzyme that can hydrolyze pectic substance. Pectinase mainly acts on the glycosidic bond between D-galactouronic acid residues in pectin, breaks and degrades the polysaccharide chain of pectin, generates oligogalacturonic acid and a small amount of galacturonic acid, so as to achieve the purpose of application.