• Korean Journal of Human Ecology
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• v.14 no.1
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• pp.217-221
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• 2005

In this study, the effect of microwave treatment on physico-chemical properties and microbial changes of beef and pork loin was investigated. Beef and pork were heated in microwave with an adjusted electric output at 500 W and operating frequency 2,450 MHz. The beef and pork samples were treated with microwave for 10 s or 20 s at 50% duty cycle. Drip losses and TBA values of beef and pork samples increased due to the microwave treatment. The samples became darker and more yellowish through microwaves, whereas their redness was unchanged. Microbial content of beef and pork samples declined as the treatment time increased. When pork samples were heated in a microwave oven, organisms were reduced by 2 log cycles in 20 s. It was concluded that a 20 second-long microwave treatment can great1y enhance the microbial safety of the pork sample.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.5
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• pp.678-688
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• 2007

In this study, we investigated the effects of ripened tomato on the Baechukimchi fermentation, by measuring sensory, physicochemical, and microbiological properties during fermentation up to 28 days. The Baechukimchi, with various levels [0, 10, 20, 30%(w/v)] of ripened tomato, was fermented at $10^{\circ}C$. The product containing 20% ripened tomato showed the highest scores for overall acceptability, sour taste, texture, sour smell, and color. The intensity characteristic scores related to sour smell and sour taste were the highest in the control, and the texture score was highest in the 20% ripened tomato sample. During fermentation, total acidity increased while pH gradually decreased. The reducing sugar and total vitamin C contents of the experimental groups with added ripened tomato were higher than those of the control. Also, the time periods to reach maximum levels of lactic acid bacteria, by log numbers of cells and total viable cells, were more delayed in the experimental groups with added ripened tomato than in the control. Overall, the results indicate that a 20% addition of ripened tomato to Baechukimchi during fermentation can enhance sensory qualities and extended the palatable period of the product.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.761-767
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• 1996

To lessen the initial level of microorganisms, electrolyzed acid-water was used as washing and brine water in the manufacturing process. On the washing and salting processes, application of electrolyzed acid-water showed a possibility to lessen the microorganism level of Chinese cabbage effectively. Microbial level of Chinese cabbage was reduced to about 1/4 level by salting and washing process with electrolyzed acid-water while Chinese cabbage salted with tap water increased to about 1.7 times. And no coliform and E. coli were detected. However significant differences between seasoning mixtures prepared with electrolyzed acid-water and with tap water were not observed in microbial levels. Relatively low level of total count in kimchi prepared with electroyzed acid-water was kept until 15 days of fermentation at $10^{\circ}C.$ Any significant difference between them was not observed after 20 days of fermentation. pH and acidity were showed the same tendencies as microbial count.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.6
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• pp.899-906
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• 1996

The physicochemical and microbiological studies were conducted to examine the effect of pineneedle(Pinu densinora Seib. et Zucc) sap on the Kimchi fermentation. Kimchi with the addition of various levels(0, 0.5, 1.0, or 1.5%) of pine needle sap was fermented either at $4^{\circ}C$ for 15 days after placing at room temperature for 24 hours(Group A) or at $15^{\circ}C$ for 15 days(Group B). pH reached the optimal value of Kimchi fermentation(pH 4.2) on day 3 and day 4~7 in 0% treatment and pine needle sap treatments, respectively, which indicated that shelf-life of Kimchi was extended by 1~4 days by the addition of pine needle sap. Total acidity was decreased by the addition of pine needle sap. More rapid decrease in pH and increase in total acidity were observed in Group B than in Group A. Reducing sugar content was reduced to approximately 80% by day 4~5 in all treatments. Total vitamin C content was reached peak on day 1 of fermentation and then decreased in all treatments. Reducing sugar and total vitamin C contents were slightly increased by the addition of pine needle sap due to the components present in pine needle sap. Total viable cell number rapidly increased to reach Peak on day 3 and then slowly decreased during the fermentation. However, total viable cell number as well as reducing sugar and total vitamin C contents did not differ between Group A and Group B. In Group A, Lactobacillus cell number in 0% treatment continued to increase to reach peak on day 9, while the numbers in pine needle sap treatments reached Peak on day 5~9 and then gradually decreased throughout the fermentation. Unlike in Group A, Lactobaillus cell numbers in pine needle sap treatments in Group B continued to increase to reach Peak on day 7. As pine needle sap levels increased, total viable cell number and Lactobacillus cell number decreased regardless of fermentation temperatures. The results of this study indicate that pine needle sap causes to delay the Kimchi fermentation by slowing down pH drop and inhibiting the Lactobacillus cell growth.

• Applied Biological Chemistry
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• v.21 no.2
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• pp.81-83
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• 1978

The effect of bentazon(3-isopropyl-1H-2,1,3-benzothiadiazine-(4)-3H-one-2,2-dioxide) at 50, 200ppm on nitrification of 100ppm applied $NH_4-N$, and on the numbers of nitrite-oxidizing bacteria, and on total bacterial and fungal populations were studied in a soil for six weeks. The herbicide retarded nitrification with increasing its treatment, which was coincident with the decrease of nitrite-oxidinzing bacterial populations. Bentazon treatment in a soil caused the decrease of total bacterial populations and inversely the increase of fungal populations for 2 weeks.

• The Korean Journal of Food And Nutrition
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• v.19 no.1
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• pp.53-57
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• 2006

In order to reduce the drying cost and to maintain the natural color of raw red pepper and also to keep the red pepper hygienically, two kinds of Kimchies made of red pepper powder and mashed red pepper were prepared. The difference of quality characteristics between Kimchi made of red pepper powder and mashed red pepper was examined during fermentation at $7^{\circ}C$. Both of two Kimchi showed the same patterns of changes in pH, acidity, total bacteria cell count and total lactic acid bacteria cell count. But Kimchi made of mashed red pepper showed lower sensory scores than red pepper powder in overall acceptability.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.05a
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• pp.358-362
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• 2005

0%, 0.0012%, 0.004%의 ${\beta}-carotene$을 lard를 첨가한후 $80^{\circ}C$, $130^{\circ}C$, $180^{\circ}C$의 온도처리로 2분간 열처리를 하고 $50^{\circ}C$에서 보관시키면서 각 기간별로 총 균수검사, 과산화물가(Peroxide Value), TBArs를 측정하여 비교하였다. 1) 미생물 총 균수 실험에서 ${\beta}-carotene$의 첨가량이 0%, 0.0012%, 0.004%로 증가함에 따라 균의 증식이 둔화되었다. 2) Peroxide Value의 측정 실험에 ${\beta}-carotene$의 첨가량이 0.004%일 때가 0%, 0.0012%에서 보다 항산화 능력이 더 높은 것으로 나타났다. 3) TBA가 측정실험에서 control과 Sample과의 비교에서 온도가 증가함에 따라 그 증가폭 커지므로 ${\beta}-carotene$의 항산화 능력이 있다는 것을 알 수 있다.

• Journal of Food Hygiene and Safety
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• v.26 no.3
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• pp.198-202
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• 2011

Rice has been the most important staple food in everyday meals of Korean people for thousands of years. Nowadays, it is getting increasingly used as flour ingredients in a variety of processed foods, so that it is consumed in more diversified ways. As a consequence, production volume of rice flour to manufacture rice cakes, noodles, breads, or confectioneries is recently getting increased in Korea. But there are not sufficient research outcomes to guarantee Korean consumers microbiological qualities of rice flour as well as rice. As a preliminary experiment, therefore, the microbiological profiles (aerobic mesophilic bacteria (AMB), spore-forming aerobic bacteria (SAB), lactic acid bacteria (LAB), yeasts and molds (YM), and Escherichia coli and coliforms) have been monitored for nine retailed white rice samples in this study. AMB counts ranged $10^2-10^6$ CFU/g for all the nine white rice samples. All the nine rice samples have SAB counts within a narrow range $(1.0{\times}10^2-2.5{\times}10^3$ CFU/g). LAB was detected in two white rice samples ($4.0{\times}10^2$ and $3.7{\times}10^3$ CFU/g), YM was detected in one white rice sample ($2.0{\times}10^2$ CFU/g) only. E. coli was not detected from all the nine samples. Coliforms were detected in one white rice sample ($4.1{\times}10$ CFU/g) only. All the rice samples were conclusively considered to have various microorganisms, though most of them are harmless and some, such as coliforms, may be harmful.

• Nuclear Engineering and Technology
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• v.1 no.1
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• pp.17-22
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• 1969

English sole (Parophrvs vetulus) fillets packaged in polymylar bags were irradiated at 500 Krad, using a Cobalt-60 irradiator and the accumulation of spoilage indices substances and bacterial growth in the irradiated and unirradiated samples were measured during 36 days of storage at 0-2$^{\circ}C$. A casein agar plate technique was developed for a direct enumeration of proteolytic bacterial population, thus enabling the determination of relative proportion of proteolytic bacteria in the total microflora at each storage interval. Irradiation at 500 Krad resulted in a ten fold reduction of microflora and throughout the storage period the level of microflora lagged behind that of the unirradiated, by as much as one thousand fold. This was accompanied by a remarkable suppression of TVB and TMA accumulation in the irradiated, never reaching a spoliage level. Proteolytic bacterial population also was reduced to below one per cent of the total viable count and remained so throughout the storage period, while proteolytic bacteria in the unirradiated increased proportionately with the storage, comprising 85.5% of the total microflora by the twenty-second day. This selective removal of proteolytic bacteria must account for the reduced rate of proteolysis occurred in the irradiated during the storage.

• Korean Journal of Food Science and Technology
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• v.27 no.1
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• pp.11-18
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• 1995

소금농도가 동치미의 발효숙성중에 미치는 영향을 조사하기 위하여, 동치미 담금액의 소금농도를 달리하여 제조한 동치미를 $4^{\circ}C$에서 85일 까지 저장하면서 pH, 총산함량, 환원당, 소금농도, 비타민 C 및 동치미 국물의 탁도 등의 이화학적 특성과 미생물학적 및 관능적 특성을 조사하였다. 전체적으로 발효가 진행됨에 따라 pH는 점차로 $pH3.93{\sim}pH3.72$까지 낮아지고, 총산함량은 0.18"$0.22%$ 까지 증가함을 보였다. 동치미 국물에서 소금농도는 감소하였지만, 동치미 무에서는 증가되어 발효$15{\sim}22$일에 동치미 무와 액사이의 소금농도가 평형상태에 도달했음을 볼 수 있었고, 이때 동치미 담금액의 초기 소금농도 1.5%, 3.0%, 4.5%, 6.3%는 각각 평형 소금농도 $1.2%{\pm}0.04%$, $2.0%{\pm}0.07%$, $2.8%{\pm}0.05%$, $4.0%{\pm}0.06%$에 도달하였다. 비타민 C와 환원당 함량은 동치미 국물에서 발효 $15{\sim}22$일 까지 점차 증가하다가 그이후로는 서서히 감소되었다. 그러나, 동치미 무에서는 같은 기간 동안에 계속적인 감소를 보였다. 동치미 국물의 탁도는 발효가 시작되면서 증가하여 발효 22일에 모든 시료에서 최대의 탁도를 보이고 그 이후로는 점차로 감소하였다. 총세균수와 젖산균수의 변화는 초기에 총세균수가 조금 많은 것을 제외하고는 발효가 진행됨에 따라 거의 비슷한 변화 양상을 보였는데 발효 $15{\sim}22$일에 젖산균수나 총세균수 모두 최대 균수를 보이고 그 이후로는 모든 시료에서 감소하였다. 관능적 평가에서는 짠맛의 정도와 전반적인 기호도에서 모두 큰 유의차를 보였으며, 특히 소금농도 3.0%의 동치미가 높은 점수를 얻어서 관능적으로 우수한 평가를 받았다.