• Applied Chemistry for Engineering
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• v.20 no.5
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• pp.557-560
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• 2009

In this study, a new wet etching method and the solution for thinning the glass with the thickness below $100{\mu}m$ were investigated. For the preparation of etching solution with low hydrofluoric acid, it was effective to use $NH_4F$ or $NH_4HF_2$ as a main ingredient with the addition of sulfuric acid or nitric acid. Influence of the composition of mixed acid solution and the temperature on the etching rate was investigated. The addition of anionic surfactant provides the function to prevent the adhesion of sludge generated by the etching reaction. A new wet etching pilot device equipped with streaming generation parts was used to test etching of commercial non-alkali glass and soda lime glass. The non-alkali glass with the thickness of 640 ${\mu}m$ and soda lime glass with the thickness of $500{\mu}m$ were etched to $45{\mu}m$ and $100{\mu}m$, respectively, by using the pilot device. After the etching by pilot device, the roughness degree of the glass surface was maintained at $0.01{\sim}0.02{\mu}m$.

• Korean Journal of Food Science and Technology
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• v.5 no.3
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• pp.178-182
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• 1973

Omija (Schizandra chinmensis Baillon) grown widely in Korea has been used as a traditional drink and as an ingredient in herbal medicine. A determination of the proximate composition, organic acids and major anthocyanins in Omija was made. 1. The proximate composition of Omija showed water to be 84.2%, protein to be 1.1%, fats to be 0.9%, reducing sugars to be 10.9% and total anthocyanins to be 0.2% in terms of weight percent of fresh, ripe Omija 2. Gas chromatography showed citric acid(3.5%), malic acid(1.4%) and succinic acid(0.2%) to be the major organic acids of the fruit. 3. The anthocyanins, the major pigments present in Omija were separated and isolated into 3 fractions using column chromatograph on insoluble polyvinylpyrrolidone. The main anthocyanin was tentatively identified as peonodin 3-glucoside on the basis of its absorptive properties before and after treatments with acid and $AlCl_3$ in the UV and visible ranges.

• Food Science of Animal Resources
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• v.31 no.1
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• pp.40-46
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• 2011

The growth profile of Bacillus cereus in ready-to-eat (RTE) food products of animal origin was examined under different temperature and incubation conditions. In sandwiches and Kimbab, B. cereus did not grow or exhibited only minimal growth at 4 and $10^{\circ}C$, but it grew rapidly at ambient temperature. In sandwiches, B. cereus did not grow efficiently at $25^{\circ}C$, however, in ham, the main ingredient of sandwiches, B. cereus growth was observed at the same temperature, with bacterial levels reaching 7.94 Log CFU/g after incubation for 24 h at $25^{\circ}C$. Toxigenicity of B. cereus was observed only at temperatures above $25^{\circ}C$. In Kimbab, B. cereus produced toxin after 9 h at $30^{\circ}C$ and after 12 h at $25^{\circ}C$. Ingredients of sandwiches and Kimbab were collected from 3 different Korean food-processing companies to investigate the source of contamination by B. cereus. Among the 13 tested food items, 6 items including ham were found to be contaminated with B. cereus. Of these ingredients, B. cereus isolates from 3 items produced enterotoxins. None of these isolates harbored the emetic toxin-producing gene. The findings of the present study can be used for risk assessments of food products, including ham and cheese, contaminated with B. cereus.

• Korean Journal of Pharmacognosy
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• v.35 no.3 s.138
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• pp.255-258
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• 2004

Chinese cabbage (Brassica campestris ssp pekinensis) is one of the most popular green vegetables in Cruciferae family, which consisted in many Korean food. All kinds of Chinese cabbage are used both fresh and cooked with certain varieties being more suitable than others for some uses. A unique dish, Kimchi, has been developed in Korea and elsewhere by fermenting Chinese cabbage and pickling it in salt solution. Though lots of beneficial effect of Kimchi on human health has been published before, it is still debatable and in vague on the active origin of the Kimchi or of the Chinese cabbage responsible for the corresponding biological activities. We have recently conducted photochemical investigation of the Chinese cabbage, which is the main ingredient of the Korean traditional food, Kimchi. The MeOH extract of Chinese cabbage was partitioned with ethylacetate and BuOH, successively. The ethyl acetate soluble part was subjected to column chromatography with silica gel and RP-18, which gave finally five minor components, i.e., ${\beta}-sitosterol$ (1), indole-3-acetonitrile (2), 4-methoxyindole-3-acetonitrile (3), methyl ferulate (4), glycerol 1-(9,12,15-octadecatrienoate) (5). The structures of them were established on the basis of spectral $(^1H-NMR,\;^{13}C-NMR)$ evidences.

• International Journal of Highway Engineering
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• v.8 no.3 s.29
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• pp.163-172
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• 2006

This study evaluated the laboratory properties of asphalt binder and mixture modified with SPC(Sulfur Polymer Cement), which consists of sulfur as a main ingredient that is an industrial by-product made from refining process of crude oil and carbon-black as an additive. Four levels of SPC modifier ratios(0, 10, 30, 50%) were evaluated in the laboratory. Superpave(Superior Performing Asphalt Pavements) system was used to determine the PG(Performance Grade) and evaluate the property of SPC modified binder at the different temperatures. IDT(Indirect Tensile Test) was performed to evaluate the resistance of fatigue and low-temperature cracking at $10^{\circ}C\;and\;-10^{\circ}C$. Wheel-tracking test was also performed to evaluate the rutting-resistance of SPC modified asphalt mixtures. Test results showed that the more SPC modifier ratios, the better rutting-resistance and the more potential of low-temperature cracking resistance. However, SPC modifier did not show the effect on the fatigue cracking resistance.

• Biomolecules & Therapeutics
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• v.20 no.1
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• pp.75-80
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• 2012

The aim of this study was to explore the role and effect of ginsenosides Rg1 on osteoblasts cultured with Ti particles. Osteoblasts from neonatal rats were cultured with particles and different doses of Rg1, the main active ingredient in ginsenosides Rg1. We found that the COX-2, $PGE_2$, TNF-${\alpha}$, IL-1, and IL -6 concentrations in the medium of cells cultured with Ti particles significantly increased as compared with that of the control cells (p<0.05 or p<0.01). In addition, cells cultured with Ti particles alone exhibited the highest concentrations of these molecules. The $PGE_2$, TNF-${\alpha}$, IL-1, and IL-6 levels in the medium of cells cultured with Rg1 were in between those of the control cells and the cells cultured with Ti particles alone. The IL-1ra level in the group cultured with Ti and medium-dose Rg1 was the highest followed by the cells cultured with Ti and high-dose Rg1 and those cultured with Ti and low-dose Rg1 (p<0.05). In conclusion, ginsenosides can reduce the levels of infl ammatory cytokines produced by osteoblasts on induction with Ti particles and can prevent prosthesis loosening.

• Food Science of Animal Resources
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• v.30 no.6
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• pp.923-929
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• 2010

Colostral whey prepared from colostrum (pooled from first six post-partum milkings) was heated for 10 min at $100^{\circ}C$ Heated colostral whey was incubated with 1% enzymes (protein equivalent basis) for 15, 30, 60, 90, and 120 min at $50^{\circ}C$. Papain, pepsin, trypsin, and alcalase produced different degrees of hydrolysis (DH), 10.66%, 12.42%, 10.83%, and 25.31%, respectively, at an incubation time of 120 min. The SDS-PAGE reveals that significant amounts of bovine serum albumin (BSA), ${\beta}$-lactoglobulin (${\beta}$-LG), and ${\alpha}$-lactalbumin (${\alpha}$-LA) survived papain digestion. In contrast, pepsin completely removed BSA but not ${\beta}$-LG present in heated colostral whey. Alcalase completely eliminated BSA, ${\beta}$-LG, and ${\alpha}$-LA. This differential hydrolysis was confirmed by reversed-phase HPLC analysis. Using ion-exchange chromatography, fraction-1 (F-1) was obtained from alcalase hydrolysate at a NaCl gradient concentration of 0.25 M. Reversed-phase HPLC chromatograms of alcalase F-1 showed numerous small peaks, which probably indicate that a variety of new peptides were produced. Iron content of alcalase F-1 was 28.94 ppm, which was the highest among all enzyme fractions, whereas iron content of colostral whey was 36.56 ppm. Main amino acids contained in alcalase F-1 were Thr (15.45%), Glu (14.12%), and Ser (10.39%). Therefore, alcalase can be used to generate good iron-binding peptides in heated colostral whey, and the resulting iron-binding peptides could be suitable as a value-added food ingredient for food supplements.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1230-1236
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• 2009

Optimum conditions for the freeze-thaw stability (FTS) of mung bean starch (MBS) paste as a main ingredient in omija-eui were investigated. For the optimization of the paste preparation condition, the FTS of MBS prepared by boiling in a shaking water bath (BMSW) or by pressure-cooking in an autoclave (PCMA) were analyzed using a response surface methodology (RSM). In addition, the effects of various additives such as gums, sugars, and emulsifier were evaluated on the FTS of MBS paste prepared under optimal conditions. The predicted maximal FTS of MBS paste prepared by the PCMA method (73%) was higher than that of the paste prepared by the BMSW method (36%). In case of additives, gellan gum and sodium alginate effectively prevented the syneresis of MBS paste in the BMSW method and in the PCMA method, respectively. The use of a fructose fatty acid ester as an emulsifier decreased syneresis in a dose-dependent, while the addition of sugars accelerated syneresis. Consequently, MBS paste for omija-eui preparation may be efficiently prepared by adding sodium alginate and fructose fatty acid ester under the optimal conditions of 4.3% MBS content, $121^{\circ}C$ heating temperature, and $89^{\circ}C$ cooling temperature by pressure-cooking in an autoclave.

• The Korean Journal of Food And Nutrition
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• v.25 no.2
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• pp.299-307
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• 2012

In this study, Kimchi usage was examined by nationwide consumers. 1,000 consumers between 20~60 years olds from 15 cities/province based on an administrative district participated in this questionnaire, which were one-on one interviews from September 23th to October 14th, 2009. 76.1% of the customers prepared Kimchi by them self, 26.9% customers received Kimchi from relatives and, 13.1% purchase Kimchi from the market. In addition, the rate of preparing Kimchi by themselves increased with age(p<0.05). 4~6 cabbage heads(34.5%) was the most preferred quantity for preparing Kimchi at a time, which was followed by more than 10 heads(25.2%) and 2~3 heads(22.9%). Chinese cabbage Kimchi was the most preferred type for purchase. 49.1% of customers purchased Kimchi at the supermarket and warehouse market and the origin of the ingredients, taste and-, price of Kimchi were considered important factors. The satisfactory scores of selling Kimchi were variety 3.60, taste 3.11, freshness of main ingredient 3.10, hygiene 2.86, -appropriate salt usage 2.99 and-, the origin of ingredients 2.94. There were significant difference between gender in taste and hygiene of selling Kimchi (p<0.05). In conclusion, to provide more appropriate Kimchi based on changes in Kimchi usage and consumption patterns at home and in the community, new types of Kimchi should be developed.

• Food Science and Preservation
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• v.9 no.2
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• pp.144-147
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• 2002

This study was conducted to investigate the effect of sub-ingredients of kimchi on the formation of carbon dioxide and vessel pressure. The pH, titratable acidity, formation of carbon dioxide and vessel pressure of kimchi prepared with different sub-ingredients were determined during storage at 10$^{\circ}C$. In the kimhi without GA, the pH decrease and acidity increase was slow during storage, but those of the kimchis without Gl, RP and SA were began to higher from 3th day after storage showed maximum values and was maintained 9th day after storage. The main sub-ingredient for formation of carbon dioxide was garlic and the gas formation was low in the kimchi without garlic. Vessel pressure in kimchi of the latter term of storage generally showed sub-atmospheric pressure and the more formation of carbon dioxide showed the more degree of sub-atmosphere.