• Preventive Nutrition and Food Science
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• v.4 no.1
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• pp.33-37
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• 1999

The antimutagenic effects of buchu kimchi and Chinese cabbage kimchi and theri cytotoxic effects against human cancer cell line were investigated in the Salmonella typhimurium system and MTT assay, respectively. Leek and Chinese cabbage were aslo evaluated in the same system. Buchu kimchi was fermented at 15 $^{\circ}C$ for 4 days . Buchu kimchi samples showed somewhat higher antimutagenic effects against aflatoxin B1(AFB1) than CHinese cabbage kimchi in Salmonella typhimurium TA100 strain. There was no difference onthe antimutagenic activity according to the length of fermentation . Leek exerted stronger antimutagenicity against AFB1 than Chinese cabbage in the Ames assay. In MTT assay, 6-day fermented buchu kimchin revealed the highest cytotoxicity against AGS human gastric adenocarcinoma cells in which 62% and 82% of the inhibition were observed wiht the addition of 100ug, 400ug/well, respectively. Buchu kimchi samples caused 60~70% inhibition on the proliferation of HT-29 at 400ug/well. Leek exhibited higher antiproliferative effect against both AGS cells and HT-29 cells than Chinese cabbage in MTT assay. From these results, it is considered that buchu kimchi has stronger antimutagenic and in vitro anticancer effects than Chinese cabbage kimchi and the high inhibition rate of buchu kimchi probably results from leek, the major ingredient of buchu kimchi .

• Journal of Food Hygiene and Safety
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• v.14 no.4
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• pp.422-427
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• 1999

Antimicrobial activity of Korean leek was effective on Staphylococcus aureus, Bacillus cereus, Bacillus subtilis, E. coli O157:H7, Pseudomonas fluorescens, Pichia membranaefaciens. Extract from raw Korean leek and that from frozen one showed antimicrobial activity; in contrast, extract stored frozen condition or extract from blanched one lost antimicrobial activity. Filtration, centrifugation, and vacuum concentration did not affect antimicrobial activity of the leek, nor did the changes in storage pHs. Addition of ground leek to soy milk, soy curd, and broth for cold noodle resulted in the prolonged shelf life by significantly reducing the number of viable cells.

• Korean Journal of Microbiology
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• v.37 no.3
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• pp.234-238
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• 2001

For the comparison of fermentation pattern of leek kimci with chinese cabbage kimchi, the changes of total viable cell number, Leuconostoc sp. bacteria, Lactobacillus sp. bacteria, pH and total sugar content of twotypes kimchies were investigated during fermentation at $20^{\circ}C$ and $10^{\circ}C$. In chinese cabbage kimchi at $20^{\circ}C$ fermentaion, the numbers of total viable cell, Leuconostoc sp. bacteria and Lactobacillus sp. bacteria reachedthe maximum level on 2nd day and reduced slowly. But in leek kimchi, the maximum numbers of total via-ble cells, Leuconostoc sp. bacteria and Lactobacillus sp. bacteria were obtained after 3 days fermentation,and the cell number of Lactobacillus sp. maintained at the maximum level oyer 15 days. At $10^{\circ}C$ fer-mentation, in both kimchies, the viable cell number of lactic acid bacteria more slowly increased anddecreased than at $20^{\circ}C$. The pH of chinese cabbage kimchi was 4.2 on 3rd day (optimal ripening phase) andmere decreased to 3.5 after 5 days, but in leek kimci the pH 4.2 could be reached after 10 days at $20^{\circ}C$. At $10^{\circ}C$, the optimal ripening pH 4.2 of chinese cabbage kimchi was reached after 6 days, but in leek kimchieven though after 24 days, the pH was maintained oyer 4.3. The total sugar contents of chinese cabbage him-chi and leek kimci were decreased continuously during fermentation. From these results, we know that thefermentation of leek kimchi proceed more slowly than chinese cabbage kimchi by the retardation of lacticacid bacteria growing in leek kimchi.

• Journal of the Korean Dietetic Association
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• v.10 no.4
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• pp.381-389
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• 2004

The purpose of this study was to investigate effectiveness of sanitization on raw vegetables not heated in foodservice operations. Microbiological examinations of food materials and cooked food with leek Gukgalli were performed in 2 HACCP-implemented foodservices (A and B) appointed by Food and Drug Administrations, and in 2 other foodservices (C and D) not implemented HACCP. 'Washing and sanitizing raw vegetables' were monitored as CCP at A and B foodservices but only washing has been done in pre-preparation at C and D foodservices. Aerobic plate counts of received leek in A and B foodservices were above $10^7$ CFU/g indicating very poor microbiological quality. After sanitization treatment (soaking for 5 minutes in chlorine water: chlorine density 50〜100 ppm), its aerobic plate counts decreased to 7.06×$10^5$ CFU/g (A foodservice) and 4.31×$10^5$ CFU/g (B foodservice), coliform and faecal coliform were not detected. With this result, the effect of microbial reduction by sanitizer was conformed. But, the conditions of leek were still not acceptable by microbiological standards for ready-to-eat foods. After three more times of rinse has been done, the microbial conditions of leek became acceptable. In C and D foodservices, aerobic plate counts of leek showed decreasing trends by 2〜4 times of washings but microbiological quality of leek after pre-preparation were unacceptable by microbiological standards for ready-to-eat foods (C foodservice: 3.58×$10^5$ CFU/g, D foodservice: 1.29×$10^9$ CFU/g). For the prevention of foodborne illness, sanitizing raw vegetables should be performed during pre-preparation of non-heated foods.

• Journal of Biosystems Engineering
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• v.30 no.4 s.111
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• pp.220-228
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• 2005

This study was conducted to investigate the main factors that contain a rotating velocity ratio between wheel and conveyor belt, a tilt angle of conveyor belt and a rotating velocity of a dick cutter for mechanization of Chinese leek harvest. In the survey on the cultivation of Chinese leek, row spacing of 350 m and cutting height of 10 mm from the ground were set up for field tests. Test equipment was designed to cut, pick up and convey Chinese leek one row by one row. From the results of material tests, pick-up height of conveyor belt was set up at $60\~90m$ from the bottom, and the strain and stress at rupture of Chinese leek was 0.487 m/m and 0.01078 MPa. An elastic coefficient of the rubber (Neoprene) of conveyor belts was 1.1077 under the strain of 0.3 nym. from the results of field tests, the tilt angle of conveyor belt was the range of $25^{\circ}\~30^{\circ}$ under consideration far space of container, the velocity ratio between vehicle and conveying belt was 1 to 2.4~1.7 at 0.1~0.3 m/s of vehicle, and optimum rotating velocity of the disk cutter was 34.8 m/s or more under consideration for soil friction.

• The Korean Journal of Food And Nutrition
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• v.23 no.4
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• pp.478-484
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• 2010

This study was performed to investigate the quality characteristics of sponge cake made with leek(Allium tuberosum Rottler) powder. In order to evaluate the physical and sensory properties of different cake, the leek powder was added to wheat flour at various ratios(3, 5, 7, 9%, w/w). The specific gravity of bread dough tends to increase with the addition of leek powder. The moisture levels of the sponge cakes made with leek powder were higher than that of the control. Crumb color values, lightness(L) and redness(a) decreased by leek powder addition, while yellowness(b) was significantly increased (p<0.05). In texture analyses, hardness, cohesiveness, springiness and gumminess decreased with the addition of leek powder. In sensory evaluations, the 3% leek powder sponge cake showed higher sensory property scores than others(p<0.05).

• Korean journal of food and cookery science
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• v.15 no.3
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• pp.258-263
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• 1999

Kimchi prepared with various amounts of leek (4. 8, 12%) were fermented at 15$^{\circ}C$ for 9 days and the changes in the contents of pectic substance and minerals were determined. Textural properties and sensory characteristics of kimchi were also evaluated after 3rd and 9th days of fermentation. During fermentation, the cutting force increased up to 7th day and then decreased slowly and that of control was higher than those of others. While the control kimchi showed an increase of hot-water-soluble pectin (HWSP) and decrease of HCI-soluble pectin (HCISP), the leek-added kimchi showed an opposite trend. In all kimchi samples, the contents of Ca, Mg and K decreased gradually, whereas that of Na increased slowly during fermentation. As the addition of leek increased in kimchi, the weaker the sourness and the better the appearance. Hardness of leek-added kimchi tended to be higher than that of control as measured by sensory evaluation. In overall acceptability, 12%-leek-added kimchi showed the highest score both at 3rd and 9th days of fermentation. These results suggested that the addition of leek improves the textural qualities of kimchi and enhances the sensory attribute such as flavor during fermentation.

• Journal of Environmental Health Sciences
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• v.34 no.6
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• pp.403-413
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• 2008

Toxic effect of methyl tert-butyl ether (MTBE), tert-butyl alcohol (TBA) and formaldehyde (FA) on microbial activity and diversity was compared in rice field, leek patch, and tidal mud flat soil samples. MTBE, TBA and FA with different concentrations were added into microcosms containing these soil samples, and placed at room temperature for 30 days. Then the microbial activities such as dehydrogenase and viable cell numbers and microbial community using a DGGE (Denaturing gradient gel electrophoresis) fingerprinting method were measured. Among the samples, dehydrogenase activity in rice field was inhibited the most by MTBE, TBA and FA. The toxic effect was higher according to the following orders: FA > MTBE > TBA. Dominant species in the microcosms contaminated with MTBE, TBA and FA were Chloroflex, Bacilli, gamma-proteobacteria in the rice field sample, Sphingobacteria, Flavobacteria, Actinobacteria, Bacilli, gamma-proteobacteria in the leek patch sample, and Sphingobacteria, Flavobacteria, delta-proteobacteria, gamma-proteobacteria in the tidal mud flat sample.

• Journal of Biosystems Engineering
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• v.32 no.6
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• pp.395-402
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• 2007

This study was carried out as basic researches to develop the leaf vegetable harvester. This study was conducted to investigate physical and rheological properties of bundled leaf vegetables with stem (Chinese leek, Crown daisy and Chamnamul) as test materials held and picked-up by a machine. Stress-strain behavior, stress relaxation, and strain recovery for the bundled materials were analyzed using simple Maxwell model. Physical and rheological properties of the materials were investigated by measuring rupture load, deformation and stress experimentally. Also, strain recovery time when unloading was measured using super high speed camera. Recorded recovery time for stress-strain behavior was0.026 s for Chinese leek with liner strain recovery, 0.046 s for Crown daisy and 0.05 s for Chamnamul with non-linear strain recovery. Furthermore, the strain recovery time for permanent deformation was 0.026 s, 0.046 s, and 0.05 s for Chinese Leek, Crown daisy and Chamnamul, respectively. Finally, strain recovery time and strain recovery ratio for the test materials were 0.17 s, 60.4% in Chinese leek, 0.12 s, 55.3% in Crown daisy, 0.15 s, 58.7% in Chamnamul. Here strain recovery time means that how fast the test materials are recovered from initial deformation and strain recovery ratio means how much the test materials are recovered from initial deformation. The above results show that the test materials can be held enough and moved by the belts.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.813-818
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• 1995

The effect of retarding the fermentation of Kimchi by the extract of leek(Allium tuberosum) were tested by measuring the changes in pH, acidity and total cell number as well as number of microorganisms involved in Kimchi fermentation such as Lactobacillus, Leuconostoc, Pediococcus, Streptococcus and yeasts. The changes of pH and acidity of Kimchi stored at $25^{\circ}C$ indicated that the shelf-life of Kimchi with leek extract was retarded by 1.5 days compared with Kimchi without leek extract. Growth of Lactobacillus, Leuconostoc, Pediococcus and yeasts in Kimchi were remarkably inhibited by adding the leek extract at the initial and the 1st day of fermentation. This result suggested the methanol extract of leek can be sucessfully used for the extension of shelf-life of Kimchi.