• The Korean Journal of Food And Nutrition
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• v.3 no.1
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• pp.69-79
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• 1990

Koryo(918-1352) made a certain progress in her culture and agriculture except the latter part of the era when the development in social economy were retarded due to military dictatorship and Mongol invasion. Despite of these external conditions, cultivations and kinds of horticulture foods were expanded With the help Of many king's agriculture first policy and the advancement in cultivating method . Among the horticulture foods, fruits such as peach, plum, Japanese apricot, apricot, cherry, pear, persimmon, pomegranate, crab apple, Jujube, grape, Chinese quince, walnut, orange, yuzu, chestnut, ginkgo nut(silvernut), pine nut, nutmeg nut, and fiat were crowed, and vegetables such as Chinese cabbage, turnip, radish, garlic, welsh onion, gynmigit, scallion, taro, malva, cucumber, white gourd, bottle gourd, water melon, eggplant, Japanese ginger, ginger and litchi were cultivated, while semi, water shieled and bamboo sprouts were taken in natural. Fruits were taken in natural or through dry, and particularly grapes were used to make wine, Flowers of Japanese apricots, some fruit trees, and chrysanthemum were also made into wine. Certain fruits were used as medicine owing to its medicinal nature. Vegetables were used to make Kimchi or to boil soup, sometimes they were dried to be kept in storage to be used in rare season and also used as medicine Increase in kinds of horticulture foods does not have any direct relation with the reform of social economy, but the fact that so many kinds of horticulture foods were cultivated and used in Koryo era shows that they elevated people's life and dietary culture.

• The Korean Journal of Pesticide Science
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• v.14 no.3
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• pp.209-218
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• 2010

There experiment were carried out to analyze for pesticide residues in 4 kinds of dried fruits collected in northern area of Seoul in 2007~2009. Total of 213 samples were analyzed. According to the results, 20 kinds of residual pesticides were detected. Residual pesticides were detected in 66 samples (31.0%) and 8 samples (3.8%) exceeded maximum residue limits (MRL). Cypermethrin, fenvalerate, endosulfan, chlorpyrifos, bifenthrin were detected frequently. The Pesticide types which were detected in dried furits were revealed in order of pyrethroid > organophosphate > organochloride > dicarboximide. Detection rates of dried fruits were dried chinese matrimony vein (53.0%), dried jujube (34.9%), dried rubi fructus (7.6%) and dried maximowiczia chinensis (4.6%). Based on these results, we investigated the risk assessment from amount of residual pesticide in dried jujube. Range of %ADI were 0.0001~0.0081%, but the value has not effected on human health.

• Korean Journal of Plant Resources
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• v.33 no.4
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• pp.293-302
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• 2020

Morphological characteristics of Ziziphus jujuba accessions, including 'Ilbon', were investigated to verify the possibility of 'Ilbon' as a breeding material. 'Ilbon' has smaller leaves and fruits and a lower total soluble solids content compared to the major Z. jujuba accessions. However, total polyphenol content and antioxidant capacity were highest in 'Ilbon' among the Z. jujuba accessions. In addition, 'Ilbon' could produce intact seeds and seed productivity of 'Ilbon' was highest compared with major Z. jujuba accessions. Principal component analysis and clustering analysis using the morphological characteristics of Z. jujuba accessions have been classified them to geographical origin. In particular, 'Ilbon' was clearly distinguished from the major Z. jujuba accessions. Therefore, 'Ilbon', which has the highest seed productivity and functional component, will be used as a material for cross breeding and will promote genetic study of Z. jujuba.

• Korean Journal of Agricultural Science
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• v.15 no.1
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• pp.95-113
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• 1988

In order to find out changes of chemical components related to browning of dried jujube, four varieties were subjected to the proximate analysis. Boeun, one of the major varieties in Korea, was sun-dried and stored for 12 months and analyzed periodically for one year. Browning, titrable acidity, pH, contents of ascorbic acid, organic acid, total amino acid, free amino acid, free sugar, hydroxymethylfurfural (HMF) and phenolic compounds were determined and compared with those of fresh jujube. The results obtained are summarized as follows; 1. In comparison with other similar fruits, jujube was high contents of ascorbic acid (62-79mg%) and carbohydrate (22-28%) excluding fiber. 2. Browning was increased in both steam-treated and nontreated plot together as storage period was prolonged. 3. Ascorbic acid content of fresh jujube was as high as 297.4mg% DB, but it was decreased to 20.2mg% DB, after 12 months storage. Therefore, loss of ascorbic acid was very great up to 93% of its original content. 4. Five kinds of organic acid, oxalic, succinic, fumaric, malic and citric acid were identified as major organic acids. It was interesting that only fumaric acid content was increased while others decreased during storage. 5. Seventeen kinds of amino acid were identified in the analysis of total amino acid content. Major amino acids were found to be proline, threonine, glutamic acid and lysine. During 12 months storage, 30% of original total amino acid was decreased and this was mostly accounted for free amino acids. 6. Threonine, proline, alanine and valine were identified as free amino acids which showed 85% decrease after 12 months storage. 7. Free sugars of jujube were composed of fructose, glucose and sucrose. They showed 24% decrease after 12 months storage, Especially sucrose was not detected after 4 months storage. 8. HMF of dried jujube was isolated and identified. Its content was increased up to great extent as storage period prolonged. 9. Caffeic, ferulic and P-coumaric acid were identified as jujube phenolic compounds which were significantly decreased during storage. In conclusion, non-enzymatic browning was thought to be more important than enzymatic reaction in the dried jujube. Amino-carbonyl reaction, ascorbic acid oxidation and reaction between phenolic compounds and sugar or nitrogen compounds were observed to be related to this browning.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.323-329
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• 2014

Population of fruit flies was monitored by using methyl eugenol trap during 2010-2011 in Yezin, Myanmar. Population numbers were analyzed with meteorological factors including rainfall, temperature, relative humidity and duration of sunshine. Samples of mango, guava, and jujube fruits were collected from orchards. The fruits were kept in containers so that the species of flies infesting the fruit could be identified when the adult insects emerged and to assess damage caused by fruit flies. Regression analyses indicated that populations of fruit flies were observed to be positively correlative with rainfall, minimum temperature and relative humidity, and negatively correlative with the duration of sunshine. Eleven species of fruit flies, Bactrocera arecae, B. carambolae, B. correcta, B. dorsalis, B. kandiensis, B. latilineola, B. malaysiensis, B. neocognata, B. raiensis, B. verbascifoliae, and Carpomya vesuvina, were identified. B. correcta and B. dorsalis were the most abundant and accounted for 29.3% and 28.6% of total emerged adults in the different fruit samples. The highest percentage of fruit damage was observed on guava ($59{\pm}15.4$), followed by mango ($35.5{\pm}12.1$) while the lowest was recorded on jujube ($18.5{\pm}7.9$).

• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.758-763
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• 1997

Fresh jujubes (Zizyphus jujuba Miller) of whitish green and red ripe maturities were stored at 5 different temperatures, and quality changes through the storage were measured to find an optimal storage condition. Respiration rates and their temperature dependences for both maturities were not different from each other, which suggested non-climacteric pattern of postharvest respiration. Red ripe fruits showed heavier weight and higher content in soluble solid and ascrobic acid compared with whitish green mature fruits. Through the storage of jujubes in perforated packages tissue softening and decay were main visual quality deteriorations with the former preceding the latter. The whitish green mature jujubes showed slower rate of quality changes in softening and decay than red ripe ones, and are thus more suitable for long term storage. In the storage, the whitish green fruits changed into red color, and showed increase in soluble solid and decrease in acidity and ascorbic acid content. Storing the jujubes at $-2^{\circ}C$ resulted in symptoms of chilling injury, and storing at higher temperatures above $0^{\circ}C$ accelerated the decay and softening. $0^{\circ}C$ was found to be optimal temperature for long term storage, where jujube had the lowest rate of quality changes without chilling injury. Even at optimal temperature of $0^{\circ}C$, however, storage life retaining freshness was only around 40 days which is not enough.

• Journal of the Korean Applied Science and Technology
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• v.18 no.1
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• pp.67-77
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• 2001

In search for several fatty acid with unusual structure in vegetable oils, we have found that unknown peaks were shown on GLC in the analysis of fatty acids of the lipids from the pulp of ripened jujube (Zizypus jujuba var. inermis) fruits. These fatty acids were identified as a series of cis-monoenoic acids with ${\omega}-5$ double bond system such as $C_{14:1{\omega}5}$, $C_{16:1{\omega}5}$ and $C_{18:1{\omega}5}$, including ${\omega}-7$ fatty acid as $C_{16:1{\omega}7}$ and $C_{18:1{\omega}7}$, by GLC, solid-phase extraction silver ion-column chromatographic, GLC-mass spectrometric and IR techniques. First of all, total fatty acid methyl esters were resolved into saturated and branched fatty acid, monoenoic acid, dienoic acid, and trienoic acid fraction, respectively, with 100% dichloromethane (DCM), DCM/acetone (9:1, v/v) 100% acetone, and acetone/ acetonitrile (97:3, v/v) solvent system. Unknown fatty acids were included in the monoenoic fraction and were confirmed to have cis-configuration by IR. Picolinyl esters of monoenoic fatty acids gave distinct molecular ion peak and dominant diagnostic peaks, for example, m/z 317, 220 and 260 fragment for $cis-C_{14:1{\omega}5}$, m/z 345, m/z 248 and 288 fragment for $cis-C_{16:1{\omega}5}$ and m/z 373, m/z 276 and 316 fragment for $cis-C_{18:1{\omega}5}$. In this way the occurrence of $cis-C_{16:1{\omega}7}$ and $cis-C_{18:1{\omega}7}$ could be deduced from the appearance of prominent fragments as m/z 345, 220 and 260, and m/z 373, 248 and 280. Level of total ${\omega}-5$ fatty acids amounted to about 30% in the fatty acid composition with the predominance of $C_{16:1{\omega}5}$ $ (18.7{\sim}25.0%)$, in the semi-ripened and/or ripened samples collected in September 14 ($C_{16:1{\omega}5}$ ; 18.7%, $C_{14:1{\omega}5}$ ; 3.6% and $C_{18:1{\omega}5}$ ; 3.0%), September 22 ($C_{16:1{\omega}5}$ ; 25.0%, $C_{14:1{\omega}5}$ ; 1.4% and $C_{18:1{\omega}5}$ ; 2.6%), and October $7 (C_{16:1{\omega}5}$ ; 24.7%, $C_{14:1{\omega}5}$ ; 7.7% and $C_{18:1{\omega}5}$ ; 2.5%). However, the lipids extracted from unripened jujube in July and August contain these unusual fatty acids as low as negligible. It could be observed that the level of ${\omega}-5$ fatty acids in the pulps increased sharply with an elapse of ripening time of jujube fruits. Other monoenoic fatty acids with ${\omega}-7$ series, $C_{16:1{\omega}7}$ (palmitoleic acid) and $C_{18:1{\omega}7}$ (cis-vaccenic acid) could be detected. And in the lipids of the kernel and leaf of jujube, none of ${\omega}-5$ fatty acids could be detected.

• 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 the Korean Society of Food Science and Nutrition
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• v.37 no.8
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• pp.1090-1094
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• 2008

Treatment effects of grape fruit stem extracts (GFSE) containing trans-resveratrol or fermented pollen (FP), and ethylene gas scavenging material (EGS) on the storage property of fresh jujube (Z izyphus jujuba forma hoonensis C.S. Yook) were investigated. Fresh jujubes were packed in different storage containers (PE film and Lock & Lock vessel), and treated with GFSE containing trans-resveratrol of 30 ppm or 1% FP, and EGS. The storage vessels were stored in refrigerator ($0{\pm}1^{\circ}C$) during 12 weeks, and then quality characteristics during storage period were analysed. Hardness slightly increased until 4 weeks and decreased afterward. Soluble solid ($^{\circ}Bx$) and total titratable acidity of fresh jujube slightly increased in all treatments during storage period. Vitamin C content of fresh jujube slightly decreased in all treatments during storage period. Number of microorganisms decreased until 4 weeks and increased afterward. The decay enzyme activity increased in all treatments during storage period. Storage stability was higher for PE film than Lock & Lock containers. Storage period of fresh jujube in this experiment ranges in $8{\sim}9$ weeks for maturity fruits treated with 30 ppm of GFSE and ethylene gas scavenging material.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1242-1248
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• 2013

This study was performed to determine the effects of pretreatment (NT: non-treatment, BTS: boiling treatment with 3% sodium chloride, DTG: dipping treatment in glycerol) and drying methods (sun drying, hot air drying, and cold air drying) on the physicochemical properties and antioxidant activities of dried jujube (Zizyphus jujuba Mill.) fruits. Our results show that moisture content is lower (P<0.05) with DTG, and that moisture content is lower with hot air drying compared to other drying methods. The bulk density was highest with BTS. The soluble solids content was highest with DTG. Additionally, the soluble solids content were highest in the following order: hot air drying> cold air drying> sun drying. The titratable acidity of hot air drying was highest of all the drying methods. The titratable acidity was higher with NT and DTG, and the brix and acid ratio of sun drying was higher than other drying methods. Among the drying methods, BTS showed the best browning-retarding effect, whereas boiling treatment affected quality and color. The total polyphenol content from hot air drying and NT or DTG treatment was relatively higher than the content from BTS. The flavonoid content was highest with BTS, and all dried jujube showed relatively high antioxidant activities. The sensory evaluation results indicated that the organoleptic scores for overall preference were higher in the NT and DTG treatment groups. These results suggest that pretreatment and drying methods affect the quality of dried jujube fruit, and show that glycerol treatment with hot air drying can be applied to the production of high quality dried jujube.