• Food Science and Preservation
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• v.16 no.5
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• pp.650-655
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• 2009

This study was conducted to measure the quality characteristics of rough rice during low temperature drying by using an experimental dryer and heat pump with a capacity of 150kg at four temperature levels of 20, 30, 40, and $50^{\circ}C$. The quality and proper drying temperature of rough rice was investigated by measuring variations in moisture content, crack rates, germination rates and cooked rice. Temperatures over $40^{\circ}C$ is considered a high-temperature area, and below $40^{\circ}C$ is considered a low-temperature area. The drying rates were 0.3, 0.6, 0.9, and 1.3%/hr, and the crack ratios were 0, 1.6, 6.8, and 24.2% at the drying temperatures of 20, 30, 40, and $50^{\circ}C$, respectively, which showed that the higher the drying temperature was, the higher the drying rate and crack rate was. Therefore, 20 and $30^{\circ}C$ were found to be appropriate drying temperatures for avoiding crack formation, and $50^{\circ}C$ was inappropriate. At $40^{\circ}C$, the operation methods needed to be modified to limit cracking, such as increasing the tempering time. Also, as the drying temperature increased, the germination rate decreased. Germination rates at 20 and $30^{\circ}C$ were suitable for using the rough rice as a seed, and those at 40 and $50^{\circ}C$ were over 80%, which is the minimum allowable percentage. In the sensory evaluation of cooked rice, the quality of appearance, taste, and texture varied as a function of drying temperature. When considering these factors, the cooked rice that was dried at 20 and $30^{\circ}C$ was better than the cooked rice dried at high-temperature. Consequently, in view of drying temperature and rates, the best conditions for drying rough rice were below $30^{\circ}C$ and below 0.6%/hr.

• Food Science and Preservation
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• v.16 no.5
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• pp.629-635
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• 2009

We investigated the prolongation of freshness and quality during storage of muskmelons harvested at different times and treated with 1-MCP. The weight loss rate increased in all samples as the storage period was extended, although the weight loss of 1-MCP-treated samples was lower than that of controls, regardless of the degree of maturation. Additionally, the hardness of 1-MCP-treated samples was higher than that of controls, again independent of maturation stage. Specifically, 1-MCP treatment delayed softening of muskmelons, as 1-MCP- treated samples showed a high hardness value after 22 days of storage, whereas hardness of control samples decreased rapidly after 10 days. The soluble solid level in muskmelons harvested 92 days after planting was $14.3^{\circ}$ Brix, whereas that of fruit harvested after 90 days was $12.7^{\circ}$ Brix. There was no significant difference in the acidity of 1-MCP-treated samples and controls after 7 days of storage, although the acidity of 1-MCP-treated fruit was greater than that of controls after 13 days, regardless of the degree of maturation. The L-values (lightness) of 1-MCP treated samples were higher than those of controls for the first 10 days of storage, but the reverse was true after 13 days of storage. The b-values (yellowness) were high in control fruits during the initial period of storage, but greater in 1-MCP treated samples after 19 days of storage. The respiration rate of 1-MCP treated samples was lower than that of controls, regardless of the degree of maturation. Sensory evaluation revealed that the texture of control fruit decreased as storage time rose, whereas that of 1-MCP-treated samples did not fall until 28 or 34 days of storage (p<0.05). Overall acceptability based on a marketable score of 5 points showed that 1-MCP-treated muskmelons scored higher than controls, and remained fresher on storage.

• Food Science and Preservation
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• v.16 no.5
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• pp.612-617
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• 2009

Kimchi is a traditional pickled food using Korean Chinese cabbage(Brassica campestris var. pekinensis) and also containing phytochemicals, glucosinolates. This study was carried out to investigate the changes in the total glucosinolates levels of Kimchi using Korean Chinese cabbage of harvest time(June-July, August-September, October-November, December-April, May) according to storage temperature(4, 10, $15^{\circ}C$) and storage duration(0, 1, 3, 5, 7, 10, 14, 21 and 28 day). For determination of glucosinolates, 50g of Baechu kimchi was used for analytical sample preparation provided with an anion exchanges column and measured by UV-visible Spectrophotometer. The highest contents of water occurred at August-September during fermentation. At 15, 10, $4^{\circ}C$, the pH in all of seasonal variation of Baechu kimchi declined, especially from 0 to 3 days at $15^{\circ}C$, from 0 to 7 days at $10^{\circ}C$ and from 0 to 14 days at $4^{\circ}C$. At that storage, the total glucosinolates levels in all of seasonal variation of Kimchi declined in storage temperature. Baechu kimchi at August-September showed the highest total glucosinolates levels. Also total glucosinolates levels decreased as storage period increased. Baechu kimchi fermented at $15^{\circ}C$ for 7days decreased rapidly and reached to the lowest at the 1day(ranged from $10.3{\pm}0.70$ to $23.4{\pm}0.37{\mu}mol/g$ dry weight). At $10^{\circ}C$ for 14days were ranged from $12.9{\pm}0.29$ to $33.7{\pm}1.81{\mu}mol/g$ dry weight before fermentation and decreased rapidly at the 3day(ranged from $9.5{\pm}0.54$ to $20.5{\pm}0.61{\mu}mol/g$ dry weight). Total glucosinolates levels of Baechu kimchi fermented at $4^{\circ}C$ for 28days decreased rapidly during 7day(ranged from $9.9{\pm}0.78$ to $21.1{\pm}0.96{\mu}mol/g$ dry weight) and then slowly decreased. Therefore the total glucosinolates levels decreased during storage time and depended on harvest time and storage conditions of Kimchi.

• Food Science and Preservation
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• v.16 no.5
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• pp.605-611
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• 2009

Korean Baechu cabbage(known as Chinese cabbage) brined in 0%, 5% and 10% (all w/v) salt solutions were packed using high-density polyethylene film (HDPE-film), low-density polyethylene film (LDPE-film), or Mirafresh film (MF-film, US patent No. 5972815), and stored at 4C for 4 weeks. Changes in pH and salinity, and microorganism counts (lactic acid bacteria and total bacteria), were investigated. There was no significant difference in the pH change in cabbage stored using various films when the vegetables were not salted. However, the pH was most stable in Baechu cabbage prepared using 10% salt solution. Cabbage treated with 0%, 5%, and 10% salt showed salinity values of 0.83%, 1.17% and 1.62%(all w/w), respectively, after 4 weeks of storage by LDPE-film. When cabbage was treated with the highest concentration of salt solution, the count of lactic acid bacteria increased but that of total bacteria decreased. The pH from pH 6.10 to pH 4.32, pH 5.68, and pH 5.92 in brined cabbage packed in HDPE-film, LDPE-film, and MF-film, respectively, after 4 weeks. When MF-film was used, the pH showed the greatest stability of all films tested, regardless of the concentration of salt solution employed in brining. The counts of lactic acid bacteria and total bacteria increased by all tested films during storage. Cabbage packed by MF-film showed the lowest increase in bacterial counts. In conclusion, MF-film was found to be the most effective packaging material for Baechu cabbage and brining in 10% salt solution was optimal to enhance the shelf life of the vegetable. LDPE-film was more effective than was HDPE-film for storage of brined cabbage.

• Food Science and Preservation
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• v.23 no.7
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• pp.1050-1057
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• 2016

This study was carried out to investigate the effectiveness of Leuconostoc mesenteroides isolated from octopus baechu kimchi as a potential starter for seafood kimchi. L. mesenteroides is lactic acid bacterium currently used as a starter for kimchi production. We selected the most effective L. mesenteroides strain from the 7 strains isolated from octopus baechu kimchi and, based on biochemical properties and 16S rRNA sequencing, identified the selected strain as L. mesenteroides SK-1. The SK-1 strain exhibited acid-tolerance, good survival capacity, and excellent dextran productivity. We investigated the effects the SK-1 of starter on seafood kimchi fermentation. Octopus baechu kimchi was fermented with L. mesenteroides SK-1 at $4^{\circ}C$ for 35 d. The decrease in pH and increase in acidity in octopus baechu kimchi fermented with the SK-1 starter occurred more quickly than that in the control kimchi indicating that. Octopus baechu kimchi with SK-1 starter has a relatively slow rate of increase in lactic acid production. As a result, octopus baechu kimchi prepared with L. mesenteroides SK-1 can be maintained at a suitable ripening degree over an extended period of time compared to that of the control kimchi, Moreover, the octopus baechu kimchi started with L. mesenteroides SK-1 has excellent sensory properties, including a refreshing taste, and a weak sour odor.

• Korean Journal of Plant Resources
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• v.16 no.3
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• pp.264-274
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• 2003

Many potato genetic resources have been collected and improved for their diverse traits over the years using breeding program in KPGR. To select potential varieties for table and processing in Korea, 58 elite potato breeding lines and several 'Valley' varieties were cultivated and harvested at Korea Alpine area in 2001. The cultivated lines and varieties were evaluated using their cultural adaptability in the environment and tuber characteristics, such as the depth of tuber eye, tuber shape, skin color, flesh color, scab resistance, yield, and the resistance of hollow heart and internal brown spot disease. Additionally, in the selection of potential processing varieties, reducing sugar content (sum of glucose and fructose concentration) of tubers is critically considered, because it mainly influence on the chip color of processing potato tuber. For table stock varieties with white skin color, 'Early Valley', 'Summer Valley', 'Winter Valley', and 'Taebok Valley' were selected. In the aspect of diverse potato tuber color, several varieties were selected such as 'Golden Valley' for its yellow fresh and skin color, 'Gogu Valley', 'Juice Valley', and 'Rose Valley' for their red skin color, and 'Purple Valley' for its purple skin. Compared with world wide known processing cultivar 'Atlantic', 24 lines (or varieties) were selected for the potential potato processing industry due to their low reducing sugar contents (below 0.3％), high yield (above 4.0 ton/ha), and unique chip colors. Selected white chipping varieties were 'Taedong Valley', 'Kangshim Valley', and 'Kangwon Valley', which have 0.23％, 0.27％, and 0.29％ of reducing sugar contents, respectively. 'Bora Valley', having deep purple color in both skin and fresh, was selected for purple chip variety and has 0.26％ of reducing sugar content. Light yellow chip varieties (lines) were 'Rose Valley' and Valley 54, having 0.19％ and 0.269％ of reducing sugar content, respectively. For French frying potatoes, 'Stick Valley' of 0.22％ and Valley 72 of 0.151％ in reducing sugars were selected. All of these selected lines and 'Valley' varieties can be used as parents to improve potato genetic resources and to develop better varieties with unique traits and colors.

• Korean Journal of Plant Resources
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• v.27 no.1
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• pp.1-10
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• 2014

Essential oils of various plants have been known for potential biological effects such as antibacterial, antifungal, spasmolytic, antiplasmodial activities and insect-repellent property. Recently, the essential oils have attracted considerable interest in oral disease therapy. This essential oil has been known as being effective on easing sick house syndrome, giving forest aroma therapy effect and acting as repellent against pest. The essential oil of Pinus koraiensi, a native plant from Hongcheon-gun, Gangwon-do, was obtained by hydrodistillation. In light of its medicinal importance, in this study its composition, antibacterial activity and the reducing effect of offensive odor have been analyzed. The composition of essential oil was determined by GC and GC-MS. We have identified 14 compounds, of which 1R-${\alpha}$-pinene (19.38 %), 3-carene (10.21 %), camphene (9.82 %), limonene (9.00 %), bicyclo[2,2,1] heptan-2-ol (8.76 %) and ${\beta}$-phellandrene (7.98 %) were the main components. Essential oils from P. koraiensis, Chamaecyparis obtusa, Abies holophylla and Pinus densiflora were compared in terms of alleviating effect of malodors caused from formaldehyde, ammonia, trimethylamine and methylmercaptan. P. koraiensis essential oil was found to decrease the amounts of ammonia and trimethylamine by 75.17 % and 77.36 %, respectively. Antibacterial activity against Streptococcus mutans and Streptococcus sobrinus, which were known as oral cavity inducer, was investigated using the paper disc agar diffusion method. The inhibition zone was observed against S. mutans (5.97 mm) and S. sobrinus (1.40 mm), respectively. P. koraiensis essential oil shown effective deodorization and inhibitory activity against oral cavity in this study might be potential material in oral sanitary industry.

• Journal of Gifted/Talented Education
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• v.16 no.1
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• pp.21-42
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• 2006

The object of this research is to analyze the contents and amount of articles on gifted education in major daily newspapers dated January 1990 to December 2003, and to review the trend of social perception of gifted education with the passage of time. Following are the research question : 1. How many articles belonging to the same category appeared in the newspapers within the period of time covered by the study? 2. What kinds of articles appeared in the newspapers within the period of time covered by the study? To arrive at the answers to the problems mentioned above, 714 articles on gifted education. The period from 1990 to 2003 were divided into time frames of 5 years to facilitate the analysis of social consciousness regarding gifted education before and after the enforcement of the Early School Entering Law in 1995 and the Law for Promotion of Gifted Education in 2000. The researcher defined Period I as the years from 1990 to 1994, Period II from 1995 to 1999, and Period III from 2000 to 2003. The articles were classified by content which were significance and trend of gilled education, current policies on gifted education, information on gifted education, and social environment of gifted education. The results of the analysis are as follows: (1) The articles from 1990 to 2003 totalled 714. 130 articles were found within Period I, 213 within Period II, and 371 within Period III. Since the year 2000, when the Law for Promotion of gifted education was enforced, the amount of articles considerably increased. The articles on the trend of gifted education numbered 42 within Period I, 49 within Period II, and 81 within Period III, showing a huge increase in the last period. The articles on current policies numbered 56 within Period I, 77 within Period II, and 143 within Period III, numbering the most in the last period. This means that, even before the Law for Promotion of gifted education was enforced, there has been much interest in and discussion of the appropriate educational system for gifted children in preparation for the legal and institutional foundation of such system. Since the enforcement of the law, many institutions were established and the problem became an important social issue. The articles that most frequently appeared were about current policies on and status of gifted education. This category showed the largest numbers through all the three periods and on all the subjects. This subject represented 43.1% of the articles on gifted children within Period I, 36.2% within Period II, and 38.6% within Period III. As to the significance and trend of gifted education, this subject showed a decrease from 32.3% within Period I, 23% within Period II, and 21.8% within Period III. However, the articles in the category of information on gifted education gradually increased from they represented 5.4% of the articles on brilliant children within Period I, 7.5% within Period II, and 8.4% within Period III. The social environment articles showed an increase from Period I to Period II-- from 19.2% to 33.3%, but it went down to 31.3% within Period III. (2) As to articles on the trend of gifted education, there were many such articles found, mainly on researches and trends in other countries. As greater importance is accorded to gifted children and as the recognition of the necessity of providing specific education for them grows, more related studies are conducted and people try to adopt new trends from other countries. For the articles on the current policies of gifted education, most of them were about institutions. This means that many educational institutions have been established since the Law for Promotion of Gifted Education was enforced. Informative articles on gilled education were mostly about distinctive features of gifted children and how to tell who the brilliant children are. This fact shows the importance of identifying gifted children in order to educate them systemically and effectively.

• Korean Journal of Food Science and Technology
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• v.14 no.4
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• pp.301-308
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• 1982

Chungkook-jang Koji was fermented with rice straw at $40^{\circ}C\;and\;50^{\circ}C$ for 72 hours. The changes of proximate composition, pH, titrable acidity, nitrogen compounds, protease activity and free-amino acids during the fermentation were investigated. Moisture, lipid and protein contents remained essentially unchanged during the fermentation. The pH was gradually increased from 6.4 to 7.46 and 7.82 at $40^{\circ}C\;and\;50^{\circ}C$, respectively, after 72 hour fermentation. Amino type and water soluble nitrogen increased as fermentation progressed. however, the former slightly decreased after 60 hour fermentation. Chungkook-jang fermented at $40^{\circ}C$ showed somewhat higher protease activity than $50^{\circ}C$. However, protease activity at both fermentation temperatures showed the same trend; that is, it increased until 48 hour fermentation and thereafter decrease. Free amino acid content of Chung-kook-jang after 72 hour fermentation at $40^{\circ}C$ was 6 times greater than that of the steamed soybean, while it was 2.5 times greater at $50^{\circ}C$. Based on these results. it seems that the optimum fermentation conditions for Chungkook-jang were $40^{\circ}C$ and 72 hours.

• Korean Journal of Food Science and Technology
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• v.14 no.4
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• pp.375-381
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• 1982

The studies are conducted on the changes of soybean lipids in terms of physicochemical characteristics, lipid classess and fatty acid composition during the fermentation process of soybean Koji preparation for daenjang (soybean paste) in a model system using cooked soybean inoculated by Aspergillus oryzae. The total lipids contents were increased during soybean Koji preparation, generally iodine values decreased but acid values increased. Total lipids of soybean Koji consisted of about 90.6% neutral lipids, 7.6% phospholipids and 1.8%, glycolipids indicating that phospholipids contents of soybean Koji was increased when compared to those of cooked soybean. The major components of nonpolar lipids in soybean Koji were free fatty acids(39.6%) and triglycerids(29.2%). Free fatty acids increased as the triglycerides decreased during soybean Koji preparation by the hydrolysis of lipase action. The major components of polar lipids in soybean Koji were phosphatidyl choline and phosphatidyl ethanolamine. Differences were observed in the composition of the polar lipids of cooked soybean and soybean Koji. A little changes also occurred in fatty acid compositions of total lipids, triglycerides and free fatty acids fractions in soybean Koji preparation. Especially a considerable increase of linoleic acid in free fatty acid fraction was observed in soybean Koji.