• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.4
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• pp.583-588
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• 2002

Two microorganisms isolated from soybean curd residue (biji) were identified as Enterococcus faecium (51% homology) and Lactobacillus rhamnosus (99.5% homology) by using gram positive identification (GPI) card and API 50 CHL kit, respectively. Ent. faecium grew well in micronized full-fat soyflour (MFS) milk, indicating pH 4.9, 0.38% acidity and 1.8$\times$10$^{9}$ CFU/$m\ell$ of viable cell counts after fermentation for 20 hr. L. rhamnosus LL showed pH 6.5 and 4.6$\times$10$^{8}$ CFU/$m\ell$ viable cell counts, but enhanced acid production in MFS milk mixture fortified with skim milk or by the addition of 1% of glucose and lactose. On the other hand, Ent. faecium LL did not show increased acid production in MFS/skim milk and MFS milk fortified with sugar. The MFS/skim milk fermented by L. rhmnosus LS and Ent. faecium LL showed 600 mg% and 350 mg% lactic acid, respectively.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.845-850
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• 1989

Effect of high temperature soaking in salt solution and short time microwave heat treatment on quality of Korean pickled cucumbers during fermentation was investigated. The Korean pickled cucumbers were fermented at $25^{\circ}C$ for 10 days in 10% salt solution. The physicochemical properties measured were pH, the total acidity, hardness and the sensory properties of odor, taste and texture were also evaluated. The result showed that the effect of soaking cucumber in $80-90^{\circ}C$ hot salt solution significantly reduced the fermentation rate and softening rate of texture while a rather rapid fermentation was found for those soaked in $60-70^{\circ}C$. The effect of microwave treatment inhenced fermentation a little for short treatment but it was significantly reduced softening rate of texture by 3 minutes heating. The sensory evaluation of Korean pickled cucumber was found that heat treatments with hot solution and microwave heating had a possitive effect for reduction of softening of cucumber tissue, however odor and taste were not significantly affected.

• Korean Journal of Food Science and Technology
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• v.7 no.2
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• pp.74-81
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• 1975

Nonvolatile organic acids were determined in raw Chinese cabbage, Kimchis fermented at $6^{\circ}{\sim}7^{\circ}C$ and at $22^{\circ}{\sim}23^{\circ}C$. Total acids were isolated by ion-exchange chromatography and quantitative determination of individual acids was performed by silicic acid partition column chromatography. Acids were identified qualitatively by paper chromatography. Palatability of Kimchis was evaluated by nine pannels. Results were as follows: Maleic, fumaric, lactic, succinic, malonic, oxalic, glycolic, malic, citric, tartaric, sulphuric and phosphoric acid were found in raw Chinese cabbage. Kimchis fermented at $6^{\circ}{\sim}7^{\circ}C$, and at $22^{\circ}{\sim}23^{\circ}C$. In raw Chinese cabbage, most of organic acids were in salt form and malic acid was highest in amount. In Kimchi fermented at $6^{\circ}{\sim}7^{\circ}C$, the amount of lactic acid and succinic acid was higher than that in Kimchi fermented at $22^{\circ}{\sim}23^{\circ}C$, and, tartaric, oxalic, malic, malonic, maleic, glycolic and fumaric acids were less than those in Kimchi fermented at $22^{\circ}{\sim}23^{\circ}C$. Kimchi fermented at $6^{\circ}{\sim}7^{\circ}C$ had a more flavorous sour taste than Kimchi fermented at $22^{\circ}{\sim}23^{\circ}C$. It is assumed that large amount of lactic acid and succinic acid in Kimchi fermented st $6^{\circ}{\sim}7^{\circ}C$ have a connection with flavorous sour taste.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.1
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• pp.76-83
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• 2002

The purpose of study was to determine the effectiveness of crude IgY to S. mutans in preventing the acid production and the demineralization of primary tooth enamel in vitro. The acid production by S. mutans in Todd Hewitt broth with and without 5% sucrose was inhibited by 2.5% crude IgY, and as the concentration of crude IgY increased from 2.5% to 17.5%, the pH drop of the media after incubation continued to decrease. There were high positive correlations between the concentration of crude IgY and the pH of media in the late incubation period. The inhibition rate of demineralization of primary tooth enamel by S. mutans was determined by measuring the surface microhardness after incubation in 5% sucrose Todd Hewitt broth for 12 hours. The inhibition rate was 32.28% in 2.5% IgY, 42.28% in 7.5% IgY, 64.06% in 12.5% IgY, and 92.79% in 17.5% IgY. There was high positive correlation between the concentration of crude IgY and the surface microhardness of enamel after demineralization These results suggest that it would be possible to prevent dental caries through passive immunization using crude IgY.

• Journal of Convergence for Information Technology
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• v.10 no.8
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• pp.223-228
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• 2020

Objective of this study was to compared the amount of bacteria in the toothbrush according to the management method of the toothbrush in use and the acidity of intraoral bacteria. Toothbrushes in use in more than one month of 50 healthy adults were collected and the number of bacteria and pH of the toothbrushes were measured. When the number of brushings per day was 4, the pH 4.97 and the microbial numbers was the lowest at 42.16(104×CFU/ml). When the replacement period of the toothbrush was 1 month, the pH 5.35 and the microbial numbers was the lowest at 19.80(104×CFU/ml). When stored in the bathroom, the pH 4.78, and the microbial numbers was highest at 149.46(104×CFU/ml). As a result, in order to block the germs of the toothbrush, it is necessary to develop a method that can easily disinfect the contaminated toothbrush at home. In addition, I think that it is necessary to educate about the proper brush cleaning and storage method when teaching brushing.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.5
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• pp.311-317
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• 2000

Acid sulfate soil and potential acid sulfate soil material are worldwide in distribution and are problematic in agriculture and environment due to their present and potential acidity developed by the oxidation of sulfides. Most of them are sedimentary origin and a few cases are reported as volcanic or metamorphic origin. We report a potential acid sulfate soil material originated from volcanic activity during Mesozoic. A profile of Bongsan series-weathered nonpyritic andesite-hydrothermally altered pyrite rich andesite was studied with field examination, chemistry, and mineralogy. Once, the pyrite rich andesite was exposed to atmosphere by excavation and leveling works for a residential area and the lay out site had subsequent acidification problem of soil and surface water. The parent material and soil profile of Bongsan series had no signs of presence of pyrite and acid sulfate weathering such as yellow mottles. However, the hydrothermally altered andesite substrata contained significant amount of pyrite showing characteristics of hydrothermal origin such as cubic and pyritohedron morphology and occurrence along cracks.

• Applied Chemistry for Engineering
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• v.32 no.2
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• pp.190-196
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• 2021

Desulfurization reaction in a bubble type reactor was carried out by adding three organic acids such as acetic acid, lactic acid, and antic acid to investigate the enhancement of the desulfurization performance of low-grade limestone. Desulfurization of limestone slurry without organic acids initiated to degrade at pH 5.2 or less, whereas organic acid-added limestone slurry exhibited a stable efficiency in the initial desulfurization with slurry pH ranging 4.2~4.5. At slurry pH below 4, the desulfurization performance of limestone slurry with addition of organic acids may be related to the amount of anions produced by dissociation of the organic acids. When limestone slurry had a large amount of anions, a rapid decrease in buffer capacity of slurry pH did not occur. These results were due to the acidity and dissociation of organic acids. The desulfurization performance of low-grade limestone slurry increased in the order of acetic acid (2.6%) < lactic acid (6.4%) < formic acid (16.7%).

• Proceedings of the Korean Society of Food and Cookery Science Conference
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• 2003.10a
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• pp.76-76
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• 2003

치아우식중은 치아조직의 결손을 초래하는 치아경조직 질환으로 당분 함량이 많은 식품을 섭취시 치태 내 균인 Streptococcus mutans에 의해 많은 양의 dextrin이 생성되어 치아표면에 붙을 수 있는 끈적한 덩어리를 제공하고 치태 내에서 생성된 산이 치질 파괴에 계속적으로 작용하여 치아 우식을 유발하게 된다. 이에 본 연구에서는 아동이 즐겨먹는 간식품들을 대상으로 치아우식증을 유발시키는 여러 가지 요인들을 분석하여 치아우식 유발지수 측정법 개발에 기초 자료를 제공하고자 하였다. (중략)

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.531.2-531
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• 1986

대두유중에서 L, acidophilus와 K. fragilis를 단독발효시키는 것 보다 혼합배양 함으로써 젖산의 생성이 촉진되었는데 균간의 어떠한 상호작용에 의하여 산의 생산이 증가되었는가를 연구하였다. 대두유와 Soywhey를 사용하였을 때의 젖산 생성속도는 L. acidophilus 단독보다는 K. fragilis 와 혼합배양하는 것이 빨랐다. 이들 균을 단독 또는 혼합배양하여 경시적으로 발효 대두유중의 당 성분을 HPLC로 분석하였다. 그 결과 L. acidophilus가 발효하기 어려운 sucrosed raffinose, stachyose를 K. fragilis가 생산하는 효소에 의하여 젖산균이 발효할 수 있는 glucose, fructose로 분해되기 때문에 혼합배양 함으로써 젖산 발효가 촉진된다는 것을 알았다.

• Korean Journal Plant Pathology
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• v.12 no.2
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• pp.197-201
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• 1996

우리나라 포도재배 지역인 포천, 남양주 및 수원의 포도나무 줄기혹병에 이병된 포장으로부터 채집한 줄기혹(gall), 수액(sap) 및 근권토양으로부터 56균주의 유사 Agrobacterium를 분리하였으며, 이들 중 7균주가 포도나무 유묘의 줄기에 혹ㅇ르 형성시키는 병원성 Agrobacterium biovar의 선택배지에서의 생장, oxidase의 생성, Na L-tartrate로부터 알칼리의 성장, 2% NaCl 첨가 배지에서 생장, 3-ketolactose의 비생산, mesoerythritol과 ethanol로부터 산을 생성하지 못하는 등 Agrobacterium biovar 3인 A. vitis로 동정되었다.