The definition, classification and health function of kaki tannin were outlined and the properties, composition and molecular structure of kaki tannin were summarized in the article. The changing regularity and existence of kaki tannin in the persimmon fruit growing, removing astringency and processing were reviewed. The kaki tannin is composed of epiatechin, catechin-gallate, gallocatechin and gallocatechin-gallate by C-4, C-6 or C-8 polymerizing high polymer. The volume of kaki tannin cells become bigger, the number of them increased and the content of kaki tannin rose during the growing and ripping of persimmon fruit. While removing the astringency, the tannin cells shrieked and the kaki tannin changed from oligomer into high polymer, then astringency disappeared; The reason of reastringency during the processing is that kaki tannin hydrolyzed from non-astringent high polymer to astringent oligomer.

persimmon fruit; astringency; kaki tannin