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As a foundational study for processing persimmon leaves tea, the physico-chemical characters were investigated in persimmon leaves from Chungdo Bansi, Sagoksi, Kyungsan Bansi and Hiratanenasi during growth. Flesh weights increased rapidly until the middle of May and then decreased slightly. Moisture contents decreased continuously from 79-81% at the beginning of May during growth. Water soluble tannin contents reached 1.55-2.25%, maximum values at the middle of May and at the beginning of June, and increased again at the middle of July and then decreased. Contents of catechins, precursor of condensed tannin, indicated 12∼27 mg% at the middle of May and reached 17∼34 mg%, maximum values at the middle of June. Contents of catechin were low in order of (+)-catechin, (-)-epicatechin, (-)-epicallocatechingallate, (-)-epigallocatechin and (-)-epicatechingallate. Sugars present in persimmon leaves were composed of sucrose, glucose, fructose, raffinose and mannitol. Sucrose increased continuously, glucose and fructose decreased during growth. Raffinose content was less than 0.1%. Glucose and fructose took more than 90% until the beginning of May, and then sucrose took up 60∼80% of total sugar contents. Total vitamin C contents indicated maximum values at the middle of May and at the beginning of June in Chungdo Bansi, Sagoksi and Kyungsan Bansi, maximum vaule at the middle of July in Hiratanenasi. From the basis of these data It was suggested that proper period for picking persimmon leaves prior to processing persimmon leaves tea was from the middle of May to the beginning of June. Since maximum values for most of chemical components occurred at the middle of May and at the beginning of June and persimmon leaves thicken after the middle of June.
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