• Tribology and Lubricants
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• v.31 no.6
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• pp.258-263
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• 2015

Biodiesel is an environmentally-friendly fuel with low smoke emission because it contains about 10% oxygen. Biodiesel fuel prepared by transesterification of vegetable oil or animal fats is susceptible to auto-oxidation. The rate of auto-oxidation depends on the number of methylene double bonds contained within the fatty acid methyl or ethyl ester groups. Biodiesel may be easily oxidized under several conditions, i.e., upon exposure to sunlight, temperature, oxygen environment. Maintenance of the fuel quality of biodiesel requires the development of technologies to increase the resistance of biodiesel to oxidation. Treatment with antioxidants is a promising approach for extending the shelf-life or storage time of biodiesel. The chemical properties of various amine-based antioxidants were evaluated after synthesis of the antioxidants by condensation of phenylenediamine with alkylamines at room temperature. In general, the oxidative stability can be assessed based on various experimental parameters. Such parameters may include temperature, pressure, and the flow rate of air through the samples. The Rancimat method (EN14112) was selected because it is a rapid technique that requires very little sample and provides good precision for oxidative degradation analysis. Specifically, the EN 14112 technique provides enhanced efficiency for oxidative stability evaluation when a larger ester head group is utilized. Therefore, this technique was employed for evaluation of the oxidation stability of biodiesel by the Rancimat method (EN14112).

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.811-816
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• 1998

A fermented vegetable kimchi swells in package bags often during distribution to comsumer after storage. The swelling has been prohibited by packaging the kimchi in a modified LDPE film that has been made by filling a ceramic powders disinfecting to lactic acid bacteria and growth enhancing to vegetables. The film exhibited higher permeability to carbon dioxide and ethylene than LDPE film. The tastes of kimchi in the film sustained its optical quality longer than that in LDPE film at room temperature.

• Journal of the Korean Society of Food Culture
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• v.10 no.4
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• pp.345-355
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• 1995

This study estimated the status of dietary intake of 258 children from ages 3 to 6 living in Seoul and analyzed the correlation between the degree of children's nutrition awareness and dietary intake, to provide some basic informations on nutrition education program for their health promotion. Average height and weight of the children were 110.5 cm and 19.7 kg. And their body mass index was 16.2 and obesity index was 6.5%. Proportions of carbohydrate, protein and fat to the total calorie intakes were on the average 55.8%, 15.6% and 28.6%. Calorie intake proportion of breakfast, lunch, dinner and snack were 20.9%, 21.9%, 22.3% and 34.9%. In protein intake, proportion of animal and vegetable protein was 1.4, in fat intake pattern, P/M/S ratio was 1.2/1.2/1.0. As a consequence of analyzing the correlation between children's nutrition awareness and dietary intake, children of high awareness degree to the food value did not intake much calorie and carbohydrate, and did not choose cereals and starches, condensed fat food. As a result, dietary intake of pre-school children showed very good but partially showed a problem of over and under nutrition in quantity or in quality we hope that the result of this study could be helpful for the nutrition education program for the health and nutrition of the pre-school children.

• Journal of Nutrition and Health
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• v.30 no.7
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• pp.854-869
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• 1997

This study was conducted to evaluation the quality of meals served in elementary school based on nutrient contents and food diversity . A questionnaire was mailed to school foodservice dietitians requesting one week menus for April and October . Menus served in 388 schools from each province and from major cities in Korea were analyzed. Mean nutrient contents per meal of persons served, and food expenses per meal. Mean percentages of energy from fat was 20.2% , and was significantly l different by foodservice system. When nutrient contents were converted to amount per 1, 000kcal, all were higher than that calculated from RDA except calcium, iron, and Vitamin A. Most of these were not significantly different according to area, foodservice system, the number of persons served, and food expense per meal. Compared to 1/3 of RDA for children , many meals provided lower amounts of energy, Vit A, VitB2, and Ca. More than half of the meals provided less iron than 1/3 RDA for 10-12 years girls. Using the highest values of RDA for the elementary school age group as evaluation, criteria nutrient adequacy ratios(NAR) were lowest for Ca(0.61), Vit A(0.57), and iron(0.77). The mean adequacy ratio(MAR) was 0.86. Mean numbers of food items and dishes per meal were 15.3 and 5.1 , respectively. 66.3% of the meals provided three food groups of grain, meat, and vegetable. Except for the number of different food items served per meal, the aspect of food diversity was similar to that of nutrient contents. There was significant positive correlation between mean number of different food items served per meal and nutrient content . In summary , schools in small cities and rural areas than those in large cities, schools adapting commissary or joint management than those or density. Also the more food groups served per meal, the higher the nutrient content per meal . In summary , schools in small cities and rural areas than those in large cities, schools adapting commissary or joint management than those adapting conventional foodservice system, schools serving smaller number of persons, and schools with higher food expenses provided higher energy contents and food diversity.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.6
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• pp.582-587
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• 2015

This study was conducted to compare the plant growth and fruit quality of blueberries grown in different soil textures of Korea, in order to utilize the results for stable production and soil improvement. Rabbiteye blueberry cultivars 'Tifblue' and 'Baldwin' were planted and grown for three years from 2013 in wagner pot (1 $2000a^{-1}$) in a greenhouse of Namhae Sub-station, Institute of Horticultural and Herbal Science. The plants were grown in four soil textures, sand, sandy loam, loam and silt loam, and nutrient uptake and growth characteristics of plants were investigated. Leaf nitrogen and phosphorus contents of two cultivars grown in different soil textures ranged between 8.6 to $10.5gkg^{-1}$, which was lower than appropriate level for rabbiteye blueberry. However, the contents of potassium, calcium and magnesium in leaves were appropriate levels as $2.29{\sim}3.62gkg^{-1}$, $4.46{\sim}5.46gkg^{-1}$ and $1.45{\sim}2.12gkg^{-1}$, respectively. Nitrogen and phosphate contents in leaves were higher in the two cultivars grown in silt loam soil. There was no significant difference in plant volume and root dry weight among four soil textures in two cultivars. However, dry weight of leaves and branches were highest in loam soil. Fruit production was highest in loam and silt loam soil in two cultivars, showing negative correlation with the amount of sand in soil. However, sugar and acidity showed no correlation with sand content in soil. These results show the limit to the blueberry growth in soil that has no nutrient holding capacity; however, most of Korean soils that have good nutrient holding capacity can produce competitive fruits if the drainage is improved.

• Korean Journal of Agricultural Science
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• v.48 no.1
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• pp.33-43
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• 2021

Along with the widespread use of pesticides in the world, concerns over human health impacts are rapidly growing. There is a large body of evidence on the relationship between the exposure to pesticides and the elevated rate of chronic diseases such as different types of cancers, diabetes, neurodegenerative disorders like Parkinson, Alzheimer, and amyotrophic lateral sclerosis (ALS), birth defects, and reproductive disorders. This research assessed the health risk of pesticide residues by the dietary intake of vegetables collected from the agro-based markets of Dhaka, Bangladesh. As some of the banned pesticides were also found in vegetable samples, they may pose a higher risk because of cheaper availability and hence the government of Bangladesh should take strong measures to control these banned pesticides. Five organo phosphorus (chlorpyrifos, parathion, ethion, acephate, fenthion) and two carbamate (carbaryl and carbofuran) pesticide residues were identified in twenty four samples of two common vegetables (tomato and brinjal). The pesticide residues ranged from below a detectable limit (< 0.01) to 0.36 mg·kg^-1. Acephate, chlorpyrifos, ethion, and carbaryl were detected in only one sample, while co-occurrence occurred twice for parathion. Continuous monitoring and strict regulation should be enforced regarding the control of pesticide residues in fresh vegetables and other food commodities in Bangladesh.

• Korean Journal of Agricultural Science
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• v.47 no.4
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• pp.1011-1020
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• 2020

Efficient management systems of facilities make it possible to manage environmental conditions properly, such as the temperature, humidity and light source required for the best growth of the crops, as well as for the mass production of fruit and vegetables with high quality every year through an advanced and protected cultivation system. Powdery mildew is a type of chronic disease that is difficult to control during the production of Korean melons under a protected cultivation system, the use of which is increasing in production areas in Korea. Two Bacillus strains isolated from soil samples showed antagonistic activities against several pathogens, specifically Botrytis cinerea, Colletotrichum gloeosporioides, and Fusarium oxysporum f.sp. melonis; they were identified as Bacillus velezensis M2 and B. amyloliquefaciens M3 in a molecular biological test of the nucleotide sequences of gyrase subunit A (gyrA). The treatment was given three times at intervals of five days with 400-fold diluted cultures of B. velezensis M2 and B. amyloliquefaciens M3. This led to the inhibition of the incidence of powdery mildew disease in Korean melon leaves, which resulted in effective control efficiency against the incidence of powdery mildew disease with control values of 87% and 65%, respectively. Cultures of antagonistic microbes tested in this study can be used to increase the efficiency as part of an environmentally friendly management scheme to prevent powdery mildew disease during the protected cultivation of crops, including Korean melons.

• The Korean Journal of Food And Nutrition
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• v.34 no.3
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• pp.255-262
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• 2021

Centella asiatica (CA) is a vegetable that has been used for medicinal purposes for a long time, but it is not well known in Korea. In this study, the approximate analysis, physicochemical properties, free sugars, free amino acids and minerals of native and improved CA cultivated in Chungju area were measured. And the antioxidant contents and activities of CA solvent extracts were measured. There was no significant difference between native and improved species. As for the characteristics of CA, it was confirmed that the improved species had a large weight, size and a tough texture. Glucose was detected in native CA, fructose, glucose and sucrose were detected in improved species. A total of 15 free amino acids were detected and the content was slightly higher in improved species than in native species. The mineral content in CA was slightly higher in the improved species, and the detected minerals were Na, P, Ca, K, Mg and Fe. Polyphenols, ascorbic acid and flavonoids in each extraction solvent (water, 70% and 100% ethanol) were all higher in the improved species than in native species. And it was found that the antioxidant activities of ethanol extracts were higher than that of water.

• Food Science and Industry
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• v.53 no.3
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• pp.284-294
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• 2020

High voltage pulsed electric field technology has been attracting attention in the the food industry as an eco-friendly nonthermal process technology using electrical energy. The lack of understanding of the equipment and the burden of equipment cost have not significantly increased the commercial application, but the potential as a technology to replace the heat process has been continuously increased. Sterilization of foods using the PEF process has been applied to liquid foods with low viscosity such as fruit and vegetable juices, but recently, high viscosity smoothies, high concentrate protein drink, mixed juice, and alcoholic beverages. Studies on sterilization of solid foods such as powders, raw meats are also being conducted. Also, the application of extraction and recovery of useful ingredients, activation of active compounds, pretreatment of drying, improvement of meat quality, changes of properties of starch has been studies.

• Journal of Dairy Science and Biotechnology
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• v.38 no.4
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• pp.222-229
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• 2020

This study was conducted to develop a novel cheese tofu hybrid product by increasing the calcium content of cheese, an animal protein source, and tofu, a vegetable protein source. Both pH and moisture were lower in the cheese tofu hybrid than those values in the control group (6.03% and 72%, respectively). Protein and fat were slightly higher than in the control (15.43% and 9.91%, respectively). Total bacteria count increased at the end of the product's shelf life, but did not affect its texture. The cheese tofu hybrid displayed stronger a) red, and b) yellow coloration than the control, and its lightness (L) was lower than that of the control. The cheese tofu hybrid possessed high hardness, and displayed high values for gumminess and brittleness. Sensory evaluation by a specialized agency examined consumer preferences, purchase intentions, strengths, and weaknesses of the developed product line. A panel of 30 female volunteers in their 20s and 40s recorded an overall preference for cheese tofu of 5.40 points, fairly good. Cheese tofu was found to be better than the control tofu, with appealing differences in appearance, color, nutty aroma, chewiness, and cheese flavor.