• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.3
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• pp.407-411
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• 2000

감식초를 제조할 때 떫은감에 함유된 탄닌성분이 알콜발효균주의 생육 및 알콜발효물의 품질에 미치는 영향에 대해 조사하였다. 알콜발효균주에 대한 생육저해는 녹숙감에서 분리된 탄닌에서 가장 뚜렷했으며 그 뒤로 완숙기, 연시 탄닌 순으로 나타났고, S cerevisiae YJK20에 비해 S, kluyveri DJ97이 생육저해를 적게 받았다. 알콜발효액의 단도는 첨가한 탄닌함량이 높을수록 서서히 감소하여 0.2%, 0.3%탄닌처리고(III, IV)는 발효 3일까지 그 감소가 현저하였으나, 발효6일에는 모든 처리구에서 5.8~6.0$^{\circ}$Brix로 일정수준을 보였다. 발효액의 알콜함량은 참가한 탄닌함량이 낮을수록 단기간에 높은 알콜함량을 나타내었으나, 각 처리구의 최고 알콜함량에서는 큰 차이가 없었다. 또한 첨가한 탄닌함량이 높을수록 발효액의 a값 증가가 뚜렷하여 최종 발효액에서 갈색도를 나타내는 a/b값이 높은 것으로 나타났다. 탁도도 발효 1일에 각처리구에서 거의 동일한 수준이었으나, 알콜\ulcorner량이 최고치를 나타내는 발효 4일에는 0.3% 탄닌처리구(IV)에서 가장 높았으며, 각 처리구의 총페놀성 물질 및 가용성 탄닌의 함량은 발효가 진행됨에 따라 감사하였다.

• Journal of Korean Society of Forest Science
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• v.104 no.2
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• pp.248-253
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• 2015

This study applied the portfolio approach as a means to provide decision-making information for the establishment of the optimal production plan for non-timber products. The target items of non-timber forest product were Chestnut, Jujube, Walnut and Astringent Persimmon. The data used in this study were the annual report of forestry production cost survey which contains the annual production, annual gross income, and annual product cost from 2008 to 2013. These data were used to calculate the expected return of non-timber forest product. The objective function in the portfolio models was to minimize the expected return volatility, called risk and the constrain was to achieve the minimum expected return rate. Results indicated that the production ratio of the nuts and fruits in 2013 was 7% for Chestnut, 20% for Jujube, 5% for Walnut and 68% for Astringent Persimmon. Furthermore, portfolio presented that the production ratio was 10% for Chestnut, 9% for Jujube, 3% for Walnut and 78% for Astringent Persimmon in the near future. The cause was analyzed due to maintain stable production and income of Astringent Persimmon and Chestnut. Meanwhile, the revenue of Walnuts and Jujube was in great variation with relatively higher revenues.

• Journal of Bio-Environment Control
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• v.23 no.4
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• pp.321-328
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• 2014

This study was conducted to investigate volatile organic compounds (VOCs) of persimmon (Diospyros kaki Thunb) flower. VOCs of persimmon flower was collected via SPE (solid phase micro extraction) and determined by GC-MS according to tree age and organs such as flower and calyx. The ratio of early bloom was higher in more than 15 year old tree than other trees showing tree age was related with flowering rate. Major VOCs of persimmon flower was a-pinene, butane, caryophyllene, cubebene, lavandulol, D-limoneneylangene, ylangene, mainly included green, fruit, and floral flavors. The number of VOCs in persimmon flower was 30 compounds in 5-9 years old tree, 24 compounds in 10-14 years old tree, and 32 compounds in more than 15 years old tree. In comparison with VOCs in organs of sweet persimmon 'Fuyu' cultivar, flower has 10 compounds of VOCs and 26.35% of relative peak area, while calyx has 14 compounds and 46.28%, respectively. In astringent persimmon, flower has 6 compounds of VOCs and 17.58% of relative peak area, while calyx has 9 compounds and 50.27%, showing calyx of both cultivars has various volatile compounds. This study will contribute to provide a basic data for the fragrance industry to use the flavor of persimmon flower.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.2
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• pp.277-282
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• 2001

The effects of chitosans with two different molecular weights (150 and 37 kDa) on the clarification of persimmon vinegar were investigated. The coagulated solids increased with increasing chitosan concentrations. Chitosan treatment had no effect on pH and acidity. Turbidity, browning, contents of tannin and soluble solids decreased with increasing chitosan concentrations. An increase in chitosan concentration resulted in an increase in color L* value and a decrease in a* and b* values. Reduction in turbidity and tannin contents somewhat differed depending on the molecular weights of chitosan. In sensory evaluation, chitosan treatment did not affect color and flavor over all concentrations tested. However, astringent taste was noticeably strong by treatment with 500mg/L chitosan, resulting in low overall acceptability. Therefore, the most effective clarification of persimmon vinegar was achieved by treatment with 400mg/L chitosan, irrespective of molecular weight.

• Horticultural Science & Technology
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• v.18 no.3
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• pp.395-398
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• 2000

This study was conducted to evaluate the effect of harvest time, temperature and ethephon on the softening of astringent persimmon 'Cheongdobansi'. The persimmon was harvested on Sep. 21 (early season harvesting) and Oct. 11 (optimum season harvesting). Quality changes were evaluated at 10, 15 and $20^{\circ}C$ after ethephon treatment. Seventy percent of hardness decrease occurred during the first 2 days of treatment at 15 and $20^{\circ}C$, and hardness was slowly decreased after 6 days. The treatment of $10^{\circ}C$ was not effective on inducing fruit softening. Soluble tannin content was sharply decreased 6 days after ethephon treatment at 15 and $20^{\circ}C$ regardless the harvest time, whereas this was much slower in control. Hunter 'L' and 'b' values were increased until 2 days, and then decreased with the early harvested persimmon. The Hunter values were decreased until the 8th day of storage in fruit harvested at optimum season.

• 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.

• Korean Journal of Pharmacognosy
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• v.41 no.4
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• pp.255-263
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• 2010

Kojongsi persimmon (Diospyros kaki) is the major cultivar of astringent persimmon in southern of Korea. Kojongsi persimmon leaf has been traditionally used for acute and chronic diseases in Oriental countries. The purpose of this study was undertaken to investigate the antioxidative activities of the extract of Kojongsi persimmon leaf during growth. We investigated the antioxidant effects of the persimmon leaf extracts during growth on total polyphenol, total flavonoid, electronic donating ability (DPPH), nitrite (NO) scavenging and superoxide dismutase (SOD)-like activity. The next, we investigated the possible cell protective effects of the persimmon extract treatment against ultraviolet B (UVB)-induced injury in HaCaT keratinocytes. The contents of total polyphenol and flavonoid in leaf extract of Kojongsi persimmon were increased in time-dependent manner. In Jun, DPPH and NO radical scavenging and SOD-like activities in the leaf extract of Kojongsi persimmon was increased to the highest. However, the antioxidant activities in persimmon varieties were not any difference. The cell cytotoxicity by UVB irradation in HaCaT keratinocytes was significantly increased with the compared to the control group. However, the treatment of leaf extract of Kojongsi persimmon in HaCaT keratinocytes was shown to protective effect against UVB-induced cell cytotoxicity. These results suggest that the leaf extract of Kojongsi persimmon has potent antioxidant activity, and protective effect against UVB-induced keratinocyte injury. Thus, these properties may be contributed in the care of acute and chronic diseases.

• Food Science and Preservation
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• v.6 no.4
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• pp.398-401
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• 1999

This study was conducted to investigate the changes in qualities of soft persimmon by freezing and defrosting. Testing varieties were Sangjudungsi and Chunsdobansi that were cultivated on Sangju and Chungdo regions, chief cultivation of astringent persimmon in Kyongbuk province. Dropping time to 40 degrees below zero of the flesh was 10∼20 minutes longer in Chungdobansi than that in Sangiudungsi. Freezing temperature of astringent persimmon was 2∼3 degrees below zero. Occurence rates of cracked fruit during freezing storage were 24.5% in Sangjudungsi and 15.5% in Chungdobansi. Defrosting of Sangjudungsi and Chungdobansi took 150 minutes and 120 minutes at 5$^{\circ}C$, respectively. L values of chromaticity were some lower after defrosting than that of frozen soft persimmon, and a and b values decreased during defrosting rapidly. Soluble solid contents of frozen soft persimmon almost didn't change during freezing, that is, harvesting, softening, frosting and defrosting steps. Defrosting completion time to core part took 4 hours and 30 minutes in Sangjudungsi and 4 hours and 20 minutes in Chungdobansi at ordinary temperature (10.9∼14.8$^{\circ}C$).

• Food Science and Preservation
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• v.4 no.3
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• pp.323-330
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• 1997

Changes in antioxidative substance levels in eleven different cultivars of persimmon leaves during growth were investigated. In general, the contents of soluble phenols, L-ascorbic acid and flavonoids in astringent persimmon leaves(APL) were higher than those of nonastringent persimmon leaves(NAPL). The soluble phenol contents in APL and NAPL showed a tendency to decrease throughout leaf growth. L-ascorbic acid content in APL decreased rapidly during growth, whereas its content in NAPL reached its highest value at the late of July, and then decreased rapidly. Major flavonoids in APL and NAPL were quercetin and Kaempferol which were present in conjugate forms. Before acid hydrolysis, the contents of kaempferol and quercetin in APL and NAPL remained at a relatively constant level until the late of July, and then decreased slightly. After acid hydrolysis, kaempferol contents in APL and NAPL varied significantly by cultivar and growth stage, while quercetin contents decreased slowly until the late of July, and then increased drastically, reached a maximum at the early of August, afterward continuously decreased. These results suggest that APL harvested at the early of June may be useful as potential sources of natural antioxidants.

• Journal of the Korean Applied Science and Technology
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• v.33 no.1
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• pp.58-66
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• 2016

This study was performed to investigate drying characteristics and quality properties of dried persimmon with vacuum drying process. Drying characteristic curve of the dried persimmon showed that the constant rate drying period and falling rate drying period exist definitely. $_{\circ}Brix$, sugar content and hardness value of the dried persimmon increased as the vacuum pressure and heating temperature increased, but L value of the dried persimmon lower. The results indicated that the optimal conditions were at vacuum pressure of 40~50kPa abs., heating temperature of $30^{\circ}C$ and drying time of 3~4days.