• Applied Biological Chemistry
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• v.49 no.1
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• pp.30-34
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• 2006

The wastewater was quickly and fastly cleared by the peel extracts of astringent persimmon fruits. The degree of clearness increased with increasing concentrations (400-600 mg/l) of the peel extracts of astringent persimmon fruits. The removal rates of T-P and CODcr in wastewater with lime and the peel extracts of astringent persimmon fruits were lower than ferric chloride and aluminium sulfate at 100-200 mg/l concentration but higher at above 300 mg/l concentration. The removal rate of T-P increased with increasing concentration of the peel extracts of astringent persimmon fruits.

• Food Science and Preservation
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• v.6 no.3
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• pp.328-332
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• 1999

This study was investigated pattern changes of tannin isolated from astringent persimmon fruits. The contents of total phenolics and soluble tannins decreased as the maturing and softening of persimmon fruits proceeded. Green and mature persimmon tannins reacted with acetaldehyde. The more contents of tannin increased, the more reactions became. And the reaction of green Persimmon tannin was more active than mature persimmon tannins. But tannin from soft persimmon fruits did not react with acetaldehyde. Tannins were more polymerized during maturing and softening of fruits. So there was a little difference in chromatography of persimmon tannins. Also green and mature persimmon tannins obtained 4 bands respectively after thin layer chromatography analysis. But there was only 2 bands in soft persimmon tannin. As softening of persimmon fruits proceeded, most of tannins reacted with acetaldehyde, so coagulated. Also the component of soluble tannins was changed during softening of persimmon fruits.

• Food Science and Preservation
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• v.12 no.3
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• pp.299-304
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• 2005

The two major tannins were separated by Sephadex LH-20 and MCI-gel CHP-20 from peel of astringent persimmon fruits. Purified tannins were identified to (+)-catechin and (+)-gallocatechin by NMR, IR spectrum and FAB-mass spectrum. The removal rate of turbidity, T-N, T-P and CODcr in wastewater with lime and (+)-gallocatechin was higher than those of (+)-catechin because (+)-gallocatechin has more hydroxyl groups. As increasing concentration of tannins from peel of astringent persimmon fruits, the removal rate of turbidity, T-N, T-P and CODcr were increased. Synergistic activity by mixed tannins(catechin+gallocatechin) was also observed.

• International Journal of Advanced Culture Technology
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• v.7 no.4
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• pp.260-267
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• 2019

Harvested de-astringent persimmon 'Fuyu' were treated with various lighting sources under low (3℃) and high (22℃) temperatures. The weight loss rate of fruits was lower in those with Red LED than Fluorescence and Blue LED under both temperature conditions. Hardness and soluble solid content of fruits were higher in those with 3℃ / Blue LED or mixed LED (Blue+Red LEDs). Beta-carotene and lycopene content of fruit peel were higher in those with 3℃ than 22℃ and with Red LED or light sources with mixed red wavelength under both temperatures. When the fruits treated with light and temperature were stored for 4 days under 3℃ / dark condition, the hardness of the fruits did not significant difference among the treatments. Taken together all the results, it would be best to treat it light sources mixed red wavelength under 3℃.

• Journal of the Korean Society of Industry Convergence
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• v.10 no.3
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• pp.137-141
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• 2007

The sugar content of persimmon fruits was decreased when food-waste compost was used. Dungsi was brighter with yellow color than that of control. The Gabjubaekmok was darker than that of control with red color. It was suggested that taste of astringent was reduced because total phenol and soluble tannin contents were reduced by that compost. The vitamin C content of persimmon fruits during storage was higher than that of control. Stability of persimmon fruits by that compost and usual compost was about the same at room temperature. At low temperature, hardness of persimmon fruits was maintained for 20days. Hardness and reducing sugar contents of persimmon fruits were increased by food-waste compost. The result was shown that there was no effect on composition of persimmon fruits by food-waste compost and maintaining hardness at room temperature, but at low temperature, the composition of persimmon fruits was changed.

• Korean Journal of Food Science and Technology
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• v.13 no.4
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• pp.261-266
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• 1981

In order to clarify the removal of astringency in persimmon fruits (Diospyros koki L.) and its mechanism, a comparative histology of tannin cells in tile cultivars of astringent persimmon fruits (Sangju Dungsi. Daegu Bansi. Cheongdo Bansi) and a sweet persimmon fruit (Fuyu) was observed. Tannin cells were widespread in all fruits tissue expert for tissue of ovule before full blossom. The epidermal cells of ovary. flower and calyx consist of tannin cell. Arrangement of tannin cells has radiated type toward the upper directions in the calyx. The major part of seed coat consisted of tannin cells. The epidermal cells of persimmon fruits were consisted of small tannin cells, and the inner part of epicarp of the astringent persimmon was consisted of stone cells, but the sweet persimmon was consisted of parenchymatous cells. It was suggested that differantiation of tannin cell In persimmon fruits occured until about the middle of August. Some tannin cells of matured astringent persimmon fruits was coagulated and wall of tannin cell produced protuberance, and most of tannin cells of matured sweet persimmon fruits was coagulated or ruptured.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.212-217
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• 2000

This study was determined protein reaction, antioxidative activity, nitrite scavening ability and antimicrobial activity of tannins isolated from astringent persimmon fruits. Tannins extracted from green persimmon fruits reacted highly with BSA(bovine serum albumin). Reactions between tannins and BSA were more active when contents of tannin were higher than that of BSA. Antioxidative abilities of green persimmon tannin were comparable to that of BHT(butylated hydroxytoluene). Green persimmon tannins exhibited remarkable nitrite-scavenging activity. Different antimicrobial activities of persimmon tannins were observed depending on the maturity. The growth of V. parahaemolyticus and E coil were highly inhibited by the addition of persimmon tannins. Tannins from soft persimmon did not have antimicrobial activities against B. subtilis and S. typhimurium.

• Food Science and Preservation
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• v.1 no.1
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• pp.15-20
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• 1994

This experiment was carried out to select the optimum thickness of polyethylene film for the nonastringency of astringent persimmon fruits during modified atmosphere(MA) storage of Cheongdo Bansi kept at 0$^{\circ}C$. The experimental plots were divided into 5 plots by film thickness(0.08, 0.10, 0.12, 0.14 and 0.16mm). The experimental items were the changes in concentration of CO2 and O2 in film brig, soluble tannin contents, loss of weight firmness and external appearance of fruits. The nonastringency of persimmon fruits can be achieved all groups excepting the 0.08mm film during MA storage. The sweet persimmon in film bag of 0.10 and 0.12mm maintained a high quality and firmness, but following the deastringency the fruits in 0.14 and 0.16mm developed off-color. The increasing of carbon dioxide level and decreasing of oxygen level in film bag created anaerobic condition at earth stage, and then it kept a constant level during stooge. According to film thickness the obvious difference in the change of soluble tannin contents external appearance and firmness were observed. It could be concluded that the optimum thickness of film for the desirable nonastringency on Cheongdo Bansi was 0.10mm.

• Horticultural Science & Technology
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• v.33 no.5
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• pp.668-674
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• 2015

This study was conducted to investigate the optimum storage temperature and the effect of ethylene on the postharvest quality of astringent persimmon (Diospyros kaki L) 'Cheongdobansi' fruits. We treated fruits with $10{\mu}L{\cdot}L^{-1}$ ethylene at 20, 15 and $10^{\circ}C$. Our results indicated that higher storage temperature rapidly reduced firmness and astringency. The soft persimmon fruits stored at $15^{\circ}C$ showed the best quality relative to the fruits stored at $20^{\circ}C$ and $10^{\circ}C$. Our findings also showed that ethylene generators, which are sold on the market, can effectively induce persimmons to soften in plastic film.

• Applied Biological Chemistry
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• v.25 no.4
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• pp.201-205
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• 1982

As a series of study on the removal of astringency and production of tannin substances, this experiment was conducted to investigate changes of tannin contents and microscopic observation on leaves of persimmon(Diospyros kaki L.). Changes of tannin contents of leaves and fruits in Daegu Bansi(astringent variety) were of similar tendency in content of total and soluble tannin during growth. It seemed therefore that tannin contents of leaves in astringent variety were closely concerned with tannin of fruits. But Fuyu(sweet variety) was different from each other during its growth. Histological form of leaves in microscopic observation had similar tendency between astringent and sweet varieties. It was observed that tannin substances were contained in epidermis cells of levels, that tannin substances were transfered in phloems of nerves system, and that tannin cell existed too in the vicinity of nerves system.