• Preventive Nutrition and Food Science
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• v.18 no.1
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• pp.50-59
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• 2013

Black jujube was made by aging dried jujube and its physiochemical characteristics, antioxidant activities and ${\alpha}$-glucosidase inhibitory activities were evaluated. The moisture and sugar contents were increased depending on the period of aging times and the pH was reduced thereby increasing acidity. The color of black jujube extract was changed from red to black resulting in decreases of Hunter color values L, a and b. As the aging progressed, sucrose was decomposed by increasing glucose and fructose, indicating higher contents of the total reducing sugars. Among the six different types of organic acids extracted from dried jujube, the levels of oxalic acid and citric acid were increased as the aging progressed. The total polyphenol contents in ethanol and water extracts of dried jujube were 7.74 and 8.12 mg/g, respectively. The water extract of black jujube aged for 48 hr contained the highest polyphenol contents at 16.82 mg/g. The 5'-hydroxymethylfurfural (5'-HMF) contents of black jujube extract significantly increased by longer aging times, and contained higher contents in the ethanol extract than water extract. The ethanol extract of black jujube showed the highest 5'-HMF content with 338.89 mg% after aging for 3 days. Also, $IC_{50}$ values of black jujube aged for 72 hr evaluated by DPPH and ABTS radical assays were 0.54 and 0.59 mg/mL, respectively. ${\alpha}$-Glucosidase inhibitory activities of black jujube at the concentration of 3.33 mg/mL (ethanol extract) increased from 65 to 80 % after aging for 72 hr.

• Food Science and Preservation
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• v.19 no.6
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• pp.901-908
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• 2012

This study was conducted to analyze the antioxidant activities of fermented black jujube and to compare these with those of dried jujube, for the development of functional materials. The antioxidative activities of dried jujube and fermented black jujube extracts were analyzed by electron-donating ability (EDA) using 1,1-diphenyl-2-picryl hydrazyl (DPPH), superoxide-dismutase-(SOD)-like activity by pyrogallol, nitrite-scavenging ability, and xanthin oxidase. The yield of the fermented black jujube extracts was higher than that of the dried jujube extracts, and that of the ethanol extracts was higher than that of the hot-water extracts. The total phenol contents of the hot-water extracts from fermented black jujube were higher. The EDA values of the hot-water and ethanol extracts from fermented black jujube and dried jujube increased with an increase in extract concentration, and were about 85% in a $1000{\mu}g/mL$ extract concentration. The SOD-like activity increased with an increase in extract concentration. The SOD-like activity of the hot-water extract from fermented black jujube was higher than that of the other extracts. The nitrite-scavenging ability at pH 1.2 of the hot-water extracts from dried jujube was higher than that of the other extracts. The xanthine oxidase inhibitory activities of the hot-water and ethanol extracts from fermented black jujube were higher than those of the other extracts, and increased along with the concentrations of the extracts.

• Food Science and Preservation
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• v.21 no.2
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• pp.199-205
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• 2014

This study was conducted to investigate the physicochemical properties and antioxidant activity of black Doragi-apple juice to increase the utilization of Doragi, which is known as a high-functional horticultural crop. To prepare the black Doragi, it was steamed for 15 days at $60^{\circ}C$ and was then dried at $30^{\circ}C$ for 3 h. The five types of black Doragi-apple juice were prepared based on different mixing ratios of black Doraji extract, apple extract, and jujube extract. The mixing ratios of black Doraji extract, apple extract, and jujube extract were 3:3:1, 4:2:1, 2:4:1, 2:2:1, and 2:6:1 for samples A, B, C, D, and E, respectively. The pH and acidity of black Doragi-apple juice were within the ranges of 3.9-4.15 and 1.26-1.51%, respectively. Black Doraji-apple juice E showed the highest sugar content (9.33 $^{\circ}Brix$), reducing sugar content (85.05 mg/mL), and sugar content/acid ratio (6.98). Based on the sensory evaluation, sample C was most preferable in terms of color, taste, sugar-acid ratio, and overall preference, except for the flavor. Black Doragi-apple juice D showed a higher total polyphenol content (706 ${\mu}g/mL$) than sample C (586.22 ${\mu}g/mL$), but there was no statistically significant difference between samples C and D in terms of antioxidant activities. Therefore, it is suggested that the best mixing ratio of black Doraji extract, apple extract, and jujube extract for the production of the best black Doragi-apple juice with excellent taste and antioxidant activities is 2:4:1 (sample C).

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.10
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• pp.1346-1355
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• 2012

This study was carried out to investigate the characteristics of black jujube and Zizyphus jujube extracts during lactic acid fermentation. Both extracts were fermented using Lactobacillus fermentum YL-3. As a result, viable cell number rapidly increased until 24 hours, after which it gradually decreased. Before lactic acid fermentation, the $IC_{50}$ of black jujube, which was 0.014 mg/mL, was lower than that of Zizyphus jujube. Further, black jujube showed stronger antioxidant activity (374.21 mg AA eq/g) than Zizyphus jujube. Contents of total polyphenolics in both extracts were 15.46 mg/g and 13.61 mg/g, respectively, whereas contents of total flavonoids were 374.21 ${\mu}g/g$ and 64.25 ${\mu}g/g$. After lactic acid fermentation, there was no significant increase in DPPH or ABTS free radical scavenging activity. Total polyphenolic content of Zizyphus jujube decreased to 12.39 mg/g upon fermentation, whereas flavonoid content significantly increased to 291.58 ${\mu}g/g$. Further, polyphenolic and flavonoid contents of black jujube increased from 15.46 mg/g to 17.46 mg/g and from 374.21 ${\mu}g/g$ to 1,135.29 ${\mu}g/g$, respectively. These results demonstrate that 9-Times Steamed and Dried increased functional components. Especially, lactic acid fermented black jujube showed remarkably high antioxidant activity. These results confirm the potential use of lactic acid fermented black jujube as a valuable resource for the development of functional foods.

• Food Science and Preservation
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• v.19 no.2
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• pp.243-248
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• 2012

The physicochemical properties and nutritional components of fermented black jujube (FBJ) were compared with those of dried jujube (DJ) to improve their utilization as food materials. The moisture contents and brix of the DJ and FBJ were 22.6% and 6.07 brix, and 10.36% and 7.23 brix, respectively. Their L values were 34.78 and 31.82, and the a and b values of DJ were higher than those of FBJ. DJ had a lower water activity level (0.75) than FBJ (0.45), but FBJ had a higher amount of reducing sugar and soluble protein than DJ. The major free sugars in the two types of jujube were fructose and glucose, and their potassium content was highest (about 90%) among minerals. Their unsaturated fatty acid contents were 51.0% and 59.83%, respectively, and the major fatty acids myristoleic acid, palmitic acid, and palmitoleic aid were detected in them.

• Journal of Korean Society of Forest Science
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• v.96 no.6
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• pp.737-741
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• 2007

Typical phytoplasma witches' broom symptoms were observed in black locust (Robinia pseudoacacia L.) in Korea. The symptoms of the disease were showing abnormally small leaves, shortened intemodes and proliferation of shoots. The phytoplasmas were detected consistently in all the symptomatic samples by the amplification with phytoplasma universal primer pairs P1/P7 and R16F2n/R2, and the expected size was 1.8 kb and 1.2 kb. However, the phytoplasma DNA was not detected in healthy seedling. Based on sequence analysis of amplified region, this phytoplasma has close homologies with aster yellow, mulberry dwarf, maize bushy stunt, ash witches' broom and sumac witches' broom phytoplasmas, more than 99.2% but showed homologies with black locust witches' broom (GeneBank Accession No. AF 244363), and jujube witches' broom, 88.6% and 87.7%, respectively. This phylogetic analysis indicates that the black locust witches' broom phytoplasma founded in korea should be classified in the Candidatus phytoplasma asteris (16Sr I) group and clearly distinct from the black locust witches' broom group 16Sr III (peach X-disease phytoplasma group).

• Korean journal of food and cookery science
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• v.24 no.2
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• pp.182-187
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• 2008

This study was performed to evaluate the possible production of a functional beverage derived from abalone and with several plants (AP). Five types of AP composites were prepared having different medicinal plant compositions (AP- I : abalone, garlic, jujube, Chinese matrimony fruit, dried orange peel, licorice root, zinger, honey; AP- II: abalone, garlic, black bean, Chinese matrimony fruit, cornus fruit, licorice root, zinger, honey; AP-III : abalone, jujube, arrow root, milk vetch, dried orange peel, licorice root, zinger, honey; AP-N: abalone, black bean, arrow root, milk vetch, cornus fruit, liquorice root, zinger, honey; AP-V : abalone, garlic, Chinese matrimony fruit, milk vetch, licorice root, zinger, honey). In vitro analysis were performed to examine the antioxidant contents and alcohol dehydrogenase activities of the composites. AP- II had the highest total phenol contents ($28.55{\pm}1.56\;mg/l00\;g$), and AP- V the highest level of flavonoids ($47.61{\pm}1.58\;mg/l00\;g$). At $78.89{\pm}0.16%$, AP- V displayed the strongest electron donating ability followed by AP-II($57.99{\pm}0.21%$) and API ($37.66{\pm}0.20%$). Reducing power was also significantly higher in AP- V. The Hydroxyl radical scavenging and SOD-like activities of all composites were less than 15% and 20%, respectively. At 12.5% alcohol concentration, ADH activity ranged from $114.47{\pm}2.18{\sim}121.39{\pm}4.36%$ and ALDH activity ranged from $100.04{\pm}2.90{\sim}129.54{\pm}4.80%$; AP- I , AP- II, and AP- Vin 12.5% of alcoholic concentration. The composites of AP- I , AP- II, and AP- V, all containing garlic and Chinese matrimony fruit, were significantly stronger than AP-III and AP-N. Finally, also at 12.5% alcoholic concentration, the ALDH activity of AP- V was higher than its ADH activity.

• Journal of the East Asian Society of Dietary Life
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• v.8 no.4
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• pp.360-378
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• 1998

Imwonshibyukji was a copying manuscript written around 1825, the 27th year of king Soonjo of the Josun Dynasty. It was a massive home encyclopedia of total 52 books and 100 volumes. The unpublished 'Jeongjoji' of its 17-20th volumes analyzed the cooking methods on the steamed rice and gruel and studied the degree of their usefulness and medical values in the light of the cooking process science. The cooking method on the steamed rice was composed of 14 items, and the general introduction outlined 6 kinds of the rice. These were all quoted from Chinese literatures. The 11 items present the methods on the general production of the rice, 2 on the cooking process, and 1 on the preservation. The main material of the rice was rice, and others were naked barley, prosomillet, foxtail millet, glutinous millet, etc. , and the secondary materials were glutinous rice, small red bean, black soybean, potato, bamboo seed, jujube, taro, gaertner, chestnut powder, persimmon power, julib(Zizania caduciflora), mangcho(Erigeron canadensis), namchok(Nandina domestica), licorice root, nitrous, peach, palmicha(schizandra, jinseng, cheonmoondong(Asparagus), and honey are mixed), etc. The literatures quoted in the rice were all 33, in which 23 were Chinese (69.7%) and 10 were Korean (30.3%). In the case of gruel, the cooking methods on the general gruel were described in 41 items, and on the gruel for a medical treatment were in 48 items, in which there was not a cooking method on the gruel but only its medical values were presented. The materials used for the general gruel were approximately 60 kinds: rice, glutinous rice, munbean, job's tears, rye, soybean, black sesame seed, antler of cervidae, chicken, crucian carp, and various medical materials, etc. The gruel was mainly used for protection and medical treatment, and partly for food for hungry people. The literatures quoted in the gruel were total 57, in which 26 were Korean(45.6%), and 31 were Chinese (54.4%). It can be their characteristics that Almost all of the Chinese literatures on the methods of the steamed rice and gruel do not exist.

• Journal of Nutrition and Health
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• v.40 no.8
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• pp.769-778
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• 2007

Using ICP-AES, we analyzed manganese content in 366 foods consumed frequently by Koreans. For the analysis, it was included a total of 366 foods such as 51 kinds of grains, 7 kinds of potatoes and starches, 7 kinds of sugars and sweeteners, 12 kinds of legumes, 11 kinds of nuts and seeds, 68 kinds of vegetables, 7 kinds of mushrooms, 33 kinds of fruits, 13 kinds of meats, 4 kinds of eggs, 48 kinds of fishes and shellfishes, 7 kinds of seaweeds, 16 kinds of milks, 8 kinds of oils and fats, 27 kinds of beverages, 34 kinds of seasonings, 13 kinds of processed foods and others. Among the grains, starches and sugars, manganese content of rice was 0.745 mg/100g. As for legumes, the content of manganese in soybean milk was 0.033 mg/100g and in black beans was 4.075 mg/100g. In nuts and seeds, the content of manganese in gingko nuts was 0.268 mg/100g while that in pine nuts was 8.872 mg/100g. Among the vegetables, manganese contents were 0.061 mg/100g in cherry tomato and 14.017 mg/100g in ginger. In mushrooms, the highest manganese content was displayed in ear mushroom at 10.382 mg/100g. Dried jujube and shrimp were found to be the fruits and fishes with high manganese contents at 2.985 mg/100g and 3.512 mg/100g, respectively. Among dairy foods, oils and beverages, manganese content was the highest in instant coffee powder at 2.577 mg/100g. Seasonings and processed foods posted 0.010 mg/100g in Sagolgomtang, instant soup and 23.846 mg/100g in pepper. In a furture, more various food for manganese content needs to be analyzed and a reliable food database should be compiled from the findings of researches in order to estimate manganese consumption accurately.

• Culinary science and hospitality research
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• v.12 no.4 s.31
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• pp.213-224
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• 2006

This study was to investigate the factors affecting drinking Korean traditional beverages and the drinking habits of college students in Seoul. The research was carried out by asking them to drink 10 kinds of traditional drinks. They were composed of 45.5% of boys and 54.5% of girls who were $18\sim21$ years old, studying food related science (63.9%), and mostly (86.6%) living in a nuclear family in collective residents (60.4%) like an apartment. The number of students whose family's monthly incomes were over 3 million won was the largest as 37.1%. Their mothers were housewives (58.4%) mostly aged $46\sim50$ as 47.0%. In the research on the preference of students for the traditional drinks, most of them, 78.7%, showed their liking for the drinks because of their good taste (61.%). The number of students who answered they got the drinks by homemaking was the largest as 39.6%. Most of them, 66.3%, preferred fruit drinks, 19.8% soda drinks, 11.4% traditional drinks and 2.5% functional drinks. 31.2% of the drinks mostly taken at home was green tea, followed by sweet rice drink, Shik-hae. Among the drinks coming into the market, sweet rice drink was preferred in general as 25.7%, and the next was green tea 16.8%, ume drink (Maesil tea) 14.9%, rice tea 13.9%, fruit punch (Sujeonggwa) 11.4%, black tea 7.9%, honey tea 4.5%, ginseng tea 2.5% and jujube tea 2.5%. In the research on 'whether the students had experience preparing the traditional drinks or not', many of them, 62.4%, answered "No". And in the questionnaire asking on 'whether they liked to receive a training on making traditional drinks or not', 87.6% of them showed their wish to get the training. In the question on the reason why the students did not like to take the training on traditional drinks, the number of students who answered that it was complicated and hard to prepare was the largest as 53.0%.