• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.202-208
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• 2006

Juice obtained from premature citrus fruits was deacidified by electrodialysis (ED), and its physicochemical and functional properties were evaluated. Total acidities decreased from 3.15 (Aug), 1.62 (Sep), and 1.45% (Oct) to 2.37 (Aug), 0.86 (Sep), and 0.74% (Oct) by electrodialysis for 100 min, respectively, whereas $^{\circ}Brix$ to acid ratio increased, and pH and color remained almost unchanged. Free sugar content of premature citrus juice remained almost unchanged, while organic acid content decreased significantly. Narirutin and hesperidin contents among flavonoids slightly, but not significantly, decreased. $K^+,\;PO_4\;^{2-},\;SO_42^-,\;and\;Cl^-$ contents decreased by ED, with $K^+$ content showing more than 60% decrease, while $Na^+$ content increased 2.5-3.5 times. Total polyphenol content and electron-donating ability decreased slightly by ED, while nitrite-scavenging ability remained almost constant. Sensory evaluation indicated juice (Sep) subjected to ED processing to $12^{\circ}Brix$ with sugar had the highest preference.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1079-1086
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• 2000

Pectinesterase inhibitor(PEI) of ripened kiwi fruit(Actinidia chinensis) was separated with affinity chromatography using CNBr-activated Sepharose 4B being covalently bound by orange pectinesterse(PE). The affinity resin strongly and selectively bound PEI, which could be eluted in high yield as a single peak by pH 9.5 without loss of inhibitory activity. The separated PEI had maintained almost inhibitory activity at $-25^{\circ}C$ and $5^{\circ}C$ during 30 days but lost it at room temperature in 4 weeks. The PEI possessed a molecular weight of 16.6 KDa, as estimated by 12.5% SDS-PAGE. PEI had optimum pH of 7.5, optimum temperature of below $10^{\circ}C$ and stability up to $70^{\circ}C$. Also, optimum inhibitory activity for PEI was obtained in 0.2 M NaCl of substrate solutions. The kind of inhibition on tomato pectinesterase was found to be noncompetitive, using citrus pectin as substrate. Fresh orange juice added with crude PEI extracts maintained almost the same cloud stability as pasteurized juice. In case of apple juice, the addition of crude PEI extracts to apple juice had decrease of L-ascorbic acid with nearly no effect on cloud loss.

• Journal of dental hygiene science
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• v.16 no.6
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• pp.464-471
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• 2016

The purpose of this study was to provide information on the labeling of nutritional components on beverages to aid in nutrition education and oral health promotion. The study was conducted to evaluate nutritional effects and risk factors associated with the consumption of different beverages with respect to oral health. A total of 52 products from seven different types of beverages were analyzed for their nutrient content, sugar content, and pH. The sugar content per serving size, based on the nutrition labeling of beverages, was highest for the milk beverages, at 26.6 g, and lowest for the teas, at 13.0 g. According to the recommendation of the World Health Organization (WHO), beverages should contain less than 10% (50 g) total sugars. Our assessment revealed that total sugars in and carbonated beverages were 53.2% and 50.0% of daily value, respectively. Therefore, the milk and carbonated beverages contained more than 50% sugars per serving size, exceeding the recommendation of WHO. The pH of the beverages, from the most acidic to the least acidic were: carbonated beverages, pH 3.0; fruit and vegetable beverages, pH 3.1; mixed beverages, pH 3.6; fruit and vegetable juices, pH 3.7; teas, pH 4.7; coffees, pH 6.6; and milk beverages, pH 6.8. The intake of acidic and sweetened beverages could potentially cause dental caries and erosion. Therefore, the results of this study could be used by oral health care professionals to counsel their patients by providing relevant information on the possibility of oral disease caused by consumption of commercial beverages.

• Journal of Food Hygiene and Safety
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• v.16 no.4
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• pp.308-314
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• 2001

This study was conducted to determine the content of heavy metals in canned foods and soft drinks available on the Korean markets. Trace metals (Pb, Cr, Cd, and Sn) were detected in 24 kinds, 120 samples by Atomic Absorption Spectrophotometer. The average concentration of heavy metals in canned foods was in the order of Sn (6.930 ppm)>Cr (0.050 ppm)>Pb (0.030 ppm)>Cd (0.008 ppm), which was the same order in soft drinks as Sn (3.519 ppm)>Cr (0.080 ppm)>Pb (0.024 ppm)>Cd (0.001 ppm). The total contents of heavy metals in canned fruits and fruit juices were relatively higher than those in cans and drinks made of vegetable and fish. It can be supposed that the high acidity owing to the organic acid of fruit itself promotes to extract metals from can materials, and although fish usually contains more heavy metals than vegetables, canned fish revealed low level because internal organs and most of skin which had more heavy metals than meat were removed throughout canning process. Because processed foods such as canned foods and soft drinks are very popular with the children and adolescence according to the change of life style and eating habit, and the possibility of exposure to heavy metals by the habitual intake of these is increasing simultaneously, it is suggested that more practical study about the process of exposure and the amount in each step is needed fur the assessment of safety.

• Journal of Nutrition and Health
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• v.42 no.3
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• pp.278-290
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• 2009

This study aims to evaluate the changes of flavonoid contents and antioxidants activity of Jeju native citrus fruits juice according to the harvest date. Flavonoids such as quercatagetin, narirutin, hesperidin and neohesperidin were contained most plentifully in the juice of Jigak (Citrus aur-antium) by 573.73 mg/100 mL, Sadoogam (C. pseudogulgul) by 393.99 mg /100 mL, Soyooja by 29.63 mg/100 mL and Jigak (C. aurantium) by 201.23 mg/100 mL in the late August, respectively. The highest contents of nob-iletin, sinensetin and tangeretin among polymethoxyflavones were found in the juice of Hongkyool (C. tachibana) by 7.39 mg/100 mL, 2.24 mg/100 mL, 0.63 mg/100 mL in the late August, respectively. 3,5,6,7,8,3',4'- Heptamet- hoxyflavone recorded the highest amount in Punkyool (C. tangerina) by 0.27 mg/100 mL in the late August, but the other polymethoxyflavones including 3',4',7,8-tetramethoxyflavone, 3',4'-dimethoxyflavone, 4'-methoxyflavone, 5,6,7,3',4',5'-hexamethoxyflavone, scutellarein tetramethylether were observed only trace amount in all the citrus fruits. Flavonoid contents in the citrus fruit juices were the highest during early maturation and decreased rapidly while ripening. Total polyphenol contents were the highest in the late August and decreased with ripening. However from the late December, the contents were increased again. Antioxidant activities of the fruits were evaluated as electron donating ability and were the lowest in the late September and increased with the fruit ripening. These results suggest that quercetagetin among all the flavonoids was most plentiful in Jigak and Dangyooja (C. grandis), so that the fruits could be used for industrial material of flavonoids and antioxidant agents.

• Journal of Nutrition and Health
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• v.56 no.4
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• pp.439-453
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• 2023

Purpose: Concerns about accelerated aging are regularly being discussed. This study analyzed the dietary status and nutritional intake of college students who are about to enter their 30s and 40s. We further suggest ways to eat healthily. Methods: Totally, 67 students attending Daegu Catholic University were provided with a three-day meal record and analyzed. Results: The average demographics of the subjects were as follows: age 23.2 ± 2.0 years, height 165.1 ± 9.0 cm, weight 65.4 ± 13.6 kg, and BMI 23.5 ± 3.9 kg/m². Overall, 76.3% of the subjects skipped breakfast. The food intake evaluation according to the food group intake pattern and the recommended number of servings determined that 38.3% of the subjects did not consume fruits and dairy products (GMVFDS = 111001), and both men and women lacked all food groups. Analysis of the nutrient intake state revealed lesser nutrient intake than the estimated energy need. Evaluation of the %RDA found that consumption of phosphorus was above the recommended amount, whereas all other nutrients were below the recommended amount. Men had a higher intake rate of phosphorus (p < 0.01), iron (p < 0.001), and sodium (p < 0.05) than women, whereas the intake rate of dietary fiber was higher in women (p < 0.05). Evaluation of the food intake by 22 food categories revealed that intake of regular grains was more in men than in women (p < 0.05) whereas women consumed significantly more mixed grains (p< 0.01). In protein foods, men consumed more meat (p < 0.01), while women consumed more eggs (p < 0.05) and beans (p < 0.05). Evaluating the fruit intake, juices were more frequently consumed by men than by women (p < 0.05). No differences were obtained in food intake and nutrient intake status according to obesity. Conclusion: Based on these results, there is an urgent requirement for attention and support for university cafeterias in order to induce changes in the eating habits of college students. Among other initiatives, this can be achieved by providing diet improvement programs and menus that consider food preferences.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.5
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• pp.316-325
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• 2001

To develope a technique for efficiently managing fertilizer for cucumber, a quick test method to quantify nitrate content in soil solution and leaf petiole juice using a simple instrument was investigated. Among the nitrate analyzing instruments such as compact ion meter, nitrate ion meter, and test strip with reflectometer, the paper test-strip used in conjunction with a hand-held reflectometer was most closely correlated with ion chromatography method in nitrate content, and then it would be suggested with a tool that a farmer can use rapidly, conveniently and accurately for nitrate analysis in a field. Nitrate content in soil solution collected by porous cup was very variable on the lapsed time after drip irrigation and the sampling positions such as soil depth and the distance from dripper. As a result, a significant correlation between nitrate contents of soil solutions and 2M KCl soil extract was not found. However, nitrate content in soil solution extracted with a volume basis (soil:water=1:2) showed the highly significant correlation with that in 2M KCl extract. Nitrate contents of cucumber leaf petiole juices was greatly different between upper and lower leaves. Eleven to sixteen positioned-leaf would be a proper sampling position to determine nitrate content in leaf petiole for evaluating nutrient state by plant tissue analysis. From the secondary regression equations between nitrate contents of soil and petiole juice and the yield of cucumber, nitrate levels for real time diagnosis were estimated as $400mg\;l^{-1}$ soil solution by porous cup. $300mg\;l^{-1}$ in a soil volume extraction, and $1400mg\;l^{-1}$ in petiole juice from spring to summer season. In addition, the maximum yield of cucumber fruit in pot test was obtained in nitrate $1500mg\;l^{-1}$ level of petiole juice, which was similar to nitrate $1400mg\;l^{-1}$ in greenhouse trial.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.3
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• pp.341-351
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• 2010

The dietary habits of 156 female college students in the Department of Food and Nutrition (n=79) and other departments (n=77) at Sahmyook University, Nowon-gu, Seoul were evaluated from September to December, 2009. All participants completed a questionnaire designed to determine the mini dietary assessment score, as well as to evaluate nutrient intake, healthrelated questions and to determine a physical score. The students in the department of food and nutrition tended to consume more vegetables than Kimchi for each meal (39.2%), fried foods twice a week (38.0%) (p<0.05) and less fruits and fruit juices (29.1%). In addition, 15.2% of students ate Samgyeopsal and Galbi less than two times a week (p<0.05). The subjects in the department of food and nutrition took less vitamin $B_1$ and more vitamin C and E than the subjects in the other departments (p<0.05). All subjects regularly exercised for 30 minutes to 1 hour (45.7%), one or two times weekly (43.5%). The subjects in the other departments consumed more nutrient supplements. Overall, 69.1% of the subjects consumed nutrient supplements. A total of 87.8% of the subjects in the other departments consumed alcoholic beverages and all subjects began to drink when they were in high school (50.4%). The primary reason given to continue drinking was to maintain good relationships with friends (76.7%). Overall, the results of this study indicate that students in the department of food and nutrition of Sahmyook university have better dietary habits and nutrient intake than those in other departments. The results highlight the necessary to introduce a practical method of inducing good dietary habits to the everyday life of students. One approach may be to provide greater opportunity for students in other departments to attend classes in the department of food and nutrition.

• Korean Journal of Plant Resources
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• v.22 no.5
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• pp.438-445
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• 2009

This study was conducted to examine the chemical characteristics, antibacterial activity and dyeability of several juices made from Persimmon cv. 'Gyeongsanbanshi'. Young fruits of persimmon were harvested at 1st August, 2006. Fruit juice was extracted soon after harvesting, some of them were stored at $4{\sim}6^{\circ}C$ for 6 months or fermented at room temperature for 6 months. $L^*$ values of vinegar was 43.5 higher than those of fresh juice and fermented liquor. Inorganic matter contents in fresh juice, fermented liquor and vinegar were higher in the order of K ($1696{\sim}2880\;mg$/100 g), Ca ($166.7{\sim}417.9\;mg$/100 g), Mg ($203.9{\sim}214.4\;mg$/100 g), P ($37.9{\sim}109.8\;mg$/100 g), Na ($13.2{\sim}23.3\;mg$/100 g) and Fe ($8.4{\sim}14.2\;mg$/100 g). Cotton fabrics dyed with the fermented liquor and vinegar had the largest inhibitory zone against the gram-positive microorganisms with range of $16.0{\sim}35.0\;mm$. Cotton fabrics dyed with the fresh juice showed $9.0{\sim}9.5\;mm$ inhibitory zone against the gram-negative microorganisms, $15.0{\sim}21.0\;mm$ with the juice stored at $4{\sim}6^{\circ}C$ for 6 months, $22.0{\sim}23.0\;mm$ with the fermented liquor and $9.0{\sim}35.0\;mm$ with vinegar. The hue of cotton fabrics dyed with the fermented liquor had a YR levels, and antibacterial activity of them were 78.5%.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.10
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• pp.1545-1554
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• 2010

Korean government will set up the nationwide food safety system with strict control of hazardous nutrients like sugar, fatty acids and sodium as well as advanced nutrition education system. In addition, almost one hundred percent of school food service rate forced the government to consider more effective ways to upgrade the nutritional status of school meals. The object of our study was to provide the data on content and consumption of sugar in school meal for the nationwide project. For this purpose, we surveyed the sugar content of 842 school meal menus and their intake level for 154 days in 8 schools in Daejeon and Chungcheong Province. Sugar contents, the sum of the quantity of 5 sugars commonly detected in food, were analysed with HPLC-RID (Refractive Index Detector). Sugar intakes were calculated by multiplying the intake of each menu to the sugar content of that menu. The sugar content was highest in the desserts, which include fruit juices, dairy products and fruits. Sugar content of side dish was high in sauces and braised foods. Sugar intake from one dish is high in beverage and dairy product, and one dish meals contribute greatly to sugar intake because of their large amount of meal intake. The average lunch meal intakes of second grade and fifth grade elementary school students were 244 g/meal and 304 g/meal, respectively. The meal intake of middle school student was 401 g/meal. The average sugar intake from one day school lunch was 4.22 g (4.03 g on elementary and 5.31 g on middle school student), which is less than 10% of daily sugar reference value for Koreans. The result of this study provides exact data of sugar intake pattern based on the content of sugar which is matched directly to the meals consumed by the students.