• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.564-567
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• 2001

Optimal bactericidal conditions of pilot scale UV-$TiO_2$ photoreractor were studied. As the inner diameter of reactor increased. the bactedcidal efficiency decreased. Similarly bactedcidal effect was elevated according to the higher concentration of $TiO_2$. however. the effect was not repressed by the highest concentration(6.000 $mg/{\ell}$)of $TiO_2$ Bactericidal effect of muscovite bead was higher than that of glass bead. When bacterial cells were applied to the photoreacter for 1. 5. and 15 min, bactericidal effects were 62, 94.3. and 99.8%, respectively. When 30 $mg/{\ell}$ of $H_2O_2$ was added to the reaction mixture and sterilized for 5 min, the bactericidal efficiency was 99.8%.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1196-1202
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• 1999

This work was to determine the microbial and physico-chemical changes of HTST-pasteurized soymilk using microwave energy. Soymilk was HTST pasteurized$(at\;90^{\circ}C\;for\;20\;sec)$ by three methods: by heating in a stainless steel tube immersed in a hot water bath(MP0), by heating in a microwave cavity to a defiled temperature and then holding in a hot water bath(MP1), and by both heating and holding in a microwave cavity(MP2). The microbial quality based on the total plate count was in the order of MP0, MP2 and MP1. The three samples pasteurized by different methods showed the similar microbial quality with respect to the coliform count, psychrotrophic bacterial count and phosphatase activity. The destruction of trypsin inhibitor was in the order of MP0, MP1 and MP2. There were no significant differences in pH, titratable acidity, viscosity and vitamin $B_2$ content before and after pasteurization and among the different pasteurization methods. The similar or higher quality retention of the MP1 or MP2 supports the possibility of using microwave energy for the HTST pasteurization of soymilk and other fluid food products.

• Applied Chemistry for Engineering
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• v.22 no.3
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• pp.261-265
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• 2011

The sterilization effects of atmospheric pressure plasma with the mixture of argon and oxygen were analyzed. The plasma reactor with the shape of dielectric barrier discharge produced the uniform distribution of glow discharge and generated ozone gas effectively according to the various process parameters. The sterilization for E. coli was affected by power, oxygen ratio in the mixture gas, treatment time and distance between reactor and sample. The concentration of ozone was a major source for the sterilization of E. coli, which was enhanced by the increase of power and oxygen ratio. In this study, the effect of atmospheric pressure plasma treatment for the sterilization was confirmed and its result can deliver the atmospheric pressure plasma treatment as the novel sterilization method instead of conventional methods.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.202.1-202
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• 2003

기계적 박피와 수작업 박피로 처리된 감자와 우엉을 수도수, 염소수, 전해수A(pH 2.6), 전해수B(pH 8.5)등의 4가지 세정수로 세정 횟수를 달리하여 최소가공의 초기 단계인 박피와 세정처리에 따른 품질특성을 조사하였다 감자 박피에 최적 조건은 박피도구를 이용한 수작업 박피로 감모율 8.40%, 우엉은 brushing에 의한 박피 방법으로 감모율이 8.05%로 타 처리에 비하여 현저히 낮게 나타났다. 세정에 의한 미생물 살균효과는 수작업 박피 감자의 수도수 세정시 총균수는 처리 직후 4.5$\times$$10^4$CFU/g으로 무처리시의 4.8$\times$$10^4$CFU/g와 거의 차이가 없는 반면에 전해수A에 의한 세정은 $1.5\times$$10^2$CFU/g으로 나타나 뛰어난 살균효과를 나타내었고, 염소수와 전해수B로 세정된 시료도 각각 3.0$\times$$10^2$CFU/g 및 2.5$\times$$10^2$CFU/g로 나타나 전해수 처리구가 수도수 처리구에 비하여 전반적으로 2 log cycle 정도 낮은 수준으로 감소하였다. 이와 같은 살균효과는 대장균군수의 경우에도 마찬가지로 나타났다. 염소수 세정은 수도수와 동일한 방법으로 세정후 시간 경과에 따라 건조에 의한 표면색도가 점차 밝게 변하는 특징을 보였다. 마찬가지로 박피 우엉의 세정처리에 있어서도 전체적으로 전해수가 타 세정수보다 미생물 살균효과를 나타내었으며 특히, 감자에서와는 달리 1회 세정보다 2회 세정시 더 우수한 살균효과를 보여주었다.

• Asian Journal of Turfgrass Science
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• v.26 no.2
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• pp.102-109
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• 2012

Commercial formulation of fungicides was studied in the golf course for evaluation against Typhula incarnata causal agents of gray snow mold. Efficacies of fungicides application, fungicide mixture, fungicides applied method (irrigation and spray) and fungicides applied time (early fall and late fall) were evaluated for their influence on the chemical control of gray snow mold of turfgrass during the winter season in Yongpyeong golf course, Korea. Unsprayed control has significantly more disease severity than three fungicides (azoxystrobin, propiconazole, and tebuconazole) were applied to field plots. Effect of three fungicides was over 80% with control value for controlling gray snow mold on Kentucky bluegrass and creeping bentgrass species. Effect of fungicide mixture with different family groups had an over 93% control value of gray snow mold on Kentucky bluegrass species. It was not significantly difference in fungicidal effect according to applied method (irrigation and spray) with azoxystrobin on Kentucky bluegrass and creeping bentrasss species. Effect of fungicides applied time was a significantly difference on disease control by tebconazole early fall spray.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1392-1396
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• 1999

This work was to apply the microwave energy to HTST pasteurization of milk in order to prevent undesirable quality changes due to the fouling and overheating on the surface of heat exchanger. A continuous tubulartype microwave pasteurization system was designed using a domestic microwave oven(800w and 2,450MHz). Raw milk was HTST pasteurized$(at\;72^{circ}C\;for\;15\;sec)$ by three methods; by heating in a stainless steel tube immersed in a hot water bath(MP0), by heating in a microwave cavity to a desired temperature and then holding in a hot water bath(MP1) and by both heating and holding in a microwave cavity(MP2). The microbial quality based on the total plate count and Psychotrophic bacterial count was in the order MP0, MP2 and MP1 ; however, the quality difference was not significant(p<0.05) when the initial microbial numbers were involved in the statistical analysis. In addition, the three samples pasteurized by different methods showed the similar microbial quality based on the coliform count and phosphatase activity. The similar microbial quality of the three samples supports the potential use of microwave energy for the pasteurization of milk and other fluid food products.

• The Korean Journal of Pesticide Science
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• v.19 no.3
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• pp.323-328
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• 2015

Control efficacy was investigated with fungicides as 3 copper compound, 3 antibiotic fungicides and one fungicide containing to quinolone against the growth of Ralstonia solanacearum on NA medium and the disease occurrence on pepper seedlings. Among 7 fungicides, oxytetracycline was shown the highest activity against a growth of the pathogen in the agar diffusion method, but validamycin showed no activity against the pathogen. With $1000{\mu}g\;mL^{-1}$ of each copper fungicide as copper hydroxide, copper oxychloride+ dithianone and copper sulfate, 2.2, 1.3 and 1.5 mm in size of clear zone only could be found, respectively. In pepper seedling test, oxytetracycline showed a perfect activity in all treatments 7 days after inoculation. However, its activity was decreased from $500{\mu}g\;mL^{-1}$ of treatment over the time. Copper fungicides showed the control efficacy lower than antibiotic fungicides except for validamycin. Based on the results, it was suggested that it would be better to use antibiotic fungicides than copper fungicides to control pepper bacterial wilt in the fields.

• Korean Chemical Engineering Research
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• v.49 no.6
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• pp.835-839
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• 2011

The characteristics of torch-type atmospheric pressure plasma and its sterilization effects have been analyzed. The length of plasma flame was varied with the level of applied voltage and the mixture gases composed of argon and oxygen. The effect of plasma flame on the temperature increase of surface treated was limited to $43^{\circ}C$ as a maximum temperature under exposing time of 10 min. The sterilization for E. coli was strongly affected by the applied voltage, the oxygen ratio in the mixture gas and the treatment time. At a high concentration of ozone, the increase of treatment time under the direct contact with plasma flame yields to maximize the effect of the sterilization on E. coli.

• Korean Journal of Food Science and Technology
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• v.16 no.1
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• pp.95-98
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• 1984

A pilot scale continuous Kimchi pasteurizer was used to study some factors affecting the retardation of acidification of Chinese radish Kimchi, stored at $20^{\circ}C$. The degrees of acidification of Kimchi were measured in terms of pH, acidity and absorbance. The shelf-life of the pasteurization temperature from 60 to $70^{\circ}C$ did not result in any significant effect on delaying the acidification of Kimchi during storage, while lowering of storage temperature from 25 to $5^{\circ}C$ gave rise to a marked increase in the the shelf-life of Kimchi.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.189-192
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• 2001

음료수 제조공정에서 살균처리는 필수이며, 이때 살균시간과 살균온도는 맛과 향에 영향을 미친다 기존에 열에 의한 살균처리보다 살균시간과 살균온도를 낮추어 음료수의 맛과 향을 자연그대로 유지하고 품질을 개선하기 위해 초음파와 열을 병행한 살균처리연구를 수행하였다. 실험장치는 자체 개발한 연속식 heptagonal 초음파처리 조를 사용하였고, 대장균과 microbateria를 대상으로 살균처리실험을 수행하였다. 연구결과 상온초음파처리실험에서 처리속도$2\ell/min$에서 살균효과를 확인하였다. 처리용량 증대를 위해 상온초음파처리 후 저온실험결과 $3\ell/min$에서 살균효과를 확인하였다.