• Journal of Food Hygiene and Safety
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• v.15 no.4
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• pp.297-303
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• 2000

Gamma irradiation at 20 kGy was applied to Kanjang (soy sauce), Doenjang (soybean paste), Kochujang (hot pepper pasts) and Chungkukjang for their possible genotoxicity. The genotoxicity of 20 kGy-irradiated samples was evaluated by Salmonella typhimurium reversion assay. The Salmonella tester strains included TA98, TA100, TA1535 and TA1537 in the absence and presence of an exogenous metabolizing system (59 mix). All samples were negative in the bacterial reversion assay with S. typhimurium TA98, TA100, TA1535 and TA1537. The results indicated that 20 kGy of gamma irradiation on water-soluble fraction of Kanjang, Doenjang, Kochujang and Chungkukjang were not shown mutagenicity.

• Textile Coloration and Finishing
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• v.14 no.4
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• pp.249-258
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• 2002

Natural silk is formed by two proteins : the crystalline fibroin (inside the silk thread) and amorphous sericin (as a tube outside the thread). The degumming process is used to eliminate the external sericin prior to dyeing ; generally it makes use of soaps at about pH 10. Sericin is the protein constituent that "gums"together the fibroin filaments of cocoon silk. It constitutes about 25% of the weight of the cocoon, is soluble in hot water and "gels" on cooling. The removal of sericin from raw silk, known as degumming, is a simple but important process usually employing hot dilute soap or alkaline solution and occasionally dilute acids or enzymic methods. During degumming, alkali is taken up by the sericin and the free acid from the soap is formed ; this may be deposited on the fiber, reducing the rate of degumming and protecting it from hydrolysis. Alkali is often added to maintain or restore the pH of the baths, but it is rarely used alone, since it leaves the silk rather harsh in handle. If complete sericin removal is required as for printing, sodium carbonate may be added. If the pH of the bath exceeds 11, the fibroin is attacked. Recently, According to the development of electrolysis, we can be obtained the electrolytic reduction water(above pH 11.5) and electrolytic oxidation water (below pH 3). The aim of this work was to study a degumming process using electrolytic water and a possibility of sericin recovery. The new degumming process used electrolytic water operates at $95^\circ{C}$ for 2hr. without any reagents. The wastewater of this process are formed by a solution of sericin in water. This conditions suggest the study of a possible recovery of this protein (sericin) which has an amino acid composition suitable for many used in cosmetics, textile finishing agents, animal feeding, etc. The degumming process using electrolytic water is available to reduce treatment costs and pollute and at the same time to recover sericin.

• YAKHAK HOEJI
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• v.1 no.1
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• pp.2-4
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• 1948

Syringa oblata var dilatata (Nakai) Rehder is a oleaceous, deciduous shrub indigenous in the calcareous zones of Korea. The author researched the constituents of the leaves of the plant, especially the bitter principles which may be used as amara. According to the literature a bitter principle Syringin and Mannitol were isolated from the leaves of S. vulgaris L. And later on B. Power indicated that syringin and mannitol were widely distributed in oleaceous plants. The fresh leaves of the plant wer extracted with hot water, the filtered clear liquid was mixed with solution of lead acetate. The lead precipitate was filtered off and the filtered liquid was freed from lead by H$_{4}$S. The filtrate thus obtained was evaporated, and from the residue colorless needles, M. P. 166.deg., were obtained. It was soluble in water, in hot alcohol, and insoluble in ether and had a sweet taste. The results of the elementar analysis, M. P. and other characteristics agreed with that of d-mannitol. Finally it was proved to be identical with d-mannitol through conversion of it into Hexaacetyl mannitol, M. P. 124.deg., Triformal mannitol, M. P. 227.deg., Tribenzal mannitol, M. P. 224.deg., which exhibited no depression, when mixed with authentic specimens. The experiments to isolate bitter principles of the plant are in progress.

• Journal of the Korean Wood Science and Technology
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• v.25 no.1
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• pp.37-41
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• 1997

Hot-water soluble extracts were prepared from medium-sized barks of Siberian larch (Larix gmelineii). The extracts were fractionated by ultrafiltration method for producing uniform quality of adhesives. Molecular weight distribution of the extracts was ranged of 100 to 300.000. pH of the extracts affected amounts of flux, and the range of pH 6~pH 8 was proper for wood adhesives, because of easy concentration and fast gelation time. Removal of particles greater than $0.45{\mu}m$ from the extracts increased both filtration speed (flux) and yields of solids in the filtrates. In ultrafiltration process. operating pressure, filtrate temperature, and flow rate significantly increased with the increase of individual condition. Ultrafiltration using PM10 membrane was very effective to fractionate and concentrate the extracts. Removal of large particles greater than 0.45 m from the extracts increased filtration speed(flux) and yields of solids in the filtrates. A gelation time was accelerated with the increasing pH of the extracts and its concentration. The Stiasny precipitate(26%) from the filtrate obtained by PM 10 membrane was very lower than that(78%) of the retentates. This ultrafiltration method was efficient for obtaining high yield purified phenolic compounds.

• Food Science and Preservation
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• v.24 no.8
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• pp.1088-1093
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• 2017

This study was conducted to investigate the effects of drying methods for Citrus junos peels on quality characteristics of the hot-water leachate from teabags containing those peels. Fresh peels were hot-air ($50^{\circ}C$), cold-air ($30^{\circ}C$), or freeze-dried ($-45^{\circ}C$), powdered to a size of 40 mesh, packaged with a paper sachet, and then the packaged teabags were leached for 10 min with hot-water ($70^{\circ}C$). $L^*$ value (lightness) and $-a^*$ value (greenness) of the peel powder were the highest in the freeze-dried samples. Soluble solids and titratable acidity of the teabag leachate were in the following order; cold-air, freeze, and hot-air dried samples. Among free sugar contents in all samples, fructose content was the highest, followed by glucose and sucrose. Fructose and glucose contents were not affected by drying methods. There was no significant difference in the flavonoid content among the peels dried using three drying methods. DPPH radical-scavenging activity of the leachate was the highest in the cold-air dried sample. These results suggest that cold-air drying would be an effective method to enhance the quality of hot-water leachate of teabags prepared from C. junos peels.

• Food Science and Preservation
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• v.9 no.2
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• pp.184-188
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• 2002

This study was conducted to optimize hot water extraction process of cordyceps militaris for development beverage. Optimal condition for hot water extraction was investigated with changes in extraction concentration and temperature by response surface methodology. The content of soluble solid was effected with concentration. The efficiency of extraction for turbidity, total sugar, reducing sugar and protein increased with low concentration. The response variables had significant with concentration and the established polynomial model was suitable (p>0.05) model by lack-of-fit analysis. Optimal extraction conditions as the limited renditions of 2.0∼2.4% extractable solids, 1.5∼2.0% brix, l14∼120 $\mu\textrm{g}$/g total sugar, 10.5∼11.0 $\mu\textrm{g}$/ｇ reducing sugar and 110∼l15 $\mu\textrm{g}$/g protein were 95∼100$\^{C}$ and 4.0∼4.1% of concentration.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.766-770
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• 2009

Hot water extracts of Camellia japonica flower buds were found to have the higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity than the other solvent extracts. Five phenolic compounds were isolated and purified from the ethyl acetate soluble-neutral fraction of hot water extracts by Sephadex LH-20 column chromatography and octadecyl silane-high performance liquid chromatography using the guided assay of DPPH radical scavenging. Based on mass spectrometer and nuclear magnetic resonance, the isolated compounds were identified as p-hydroxybenzaldehyde (1), vanillin (2), dehydroxysynapyl alcohol (3), 7S,7'S,8R,8'R-icariol $A_2$ (4), and (-)-epicatechin (5). Four compounds (1-4) except for 5 were newly identified in this plant. Their DPPH radical scavenging activities as 50% scavenging concentration decreased in order to 5 $(20\;{\mu}M)>{\alpha}-tocopherol$ $(29\;{\mu}M)>4$ $(67\;{\mu}M)>3$ $(72\;{\mu}M)>1=2$ ($>250\;{\mu}M$). These results indicate that the antioxidant effect of the hot water extract of C. japonica flower buds may partially due to 5 isolated phenolic compounds.

• Culinary science and hospitality research
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• v.23 no.4
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• pp.1-9
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• 2017

Instant hot sauce was prepared to produce a similar product to Korean-style gochujang using different ratio of cheongguk-jang (0~20%) and red pepper powder (7~27%). Moisture content decreased from 43.21 (control: BS0) to 19.13%(maximum addition of cheongguk-jang: BS4). L value was the lowest with control (BS0), and a-value and the b-value were higher with BS4. pH tended to increase significantly as the addition amount of cheongguk-jang powder increased (p<0.001). Titratable acidity was lowest at 5.40 for BS0 and 6.30 for BS4. Salinity and soluble solids were also decreased but viscosity increased with addition of cheongguk-jang. DPPH radical scavenging activity was increased from 50.9% (BS0) to 77.6% with BS4. Overall preference was highly evaluated with the sample (BS3) prepared with red pepper, cheongguk-jang, japanese apricot extract, and water at 12, 15, 40 and 25% (w/w), respectively. Results showed that the instant hot sauce had a possibility to replace Korean-style gochujang requiring lengthy fermentation time.

• Korean Journal of Pharmacognosy
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• v.36 no.2 s.141
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• pp.102-108
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• 2005

We have studied the physico-chemical change and pharmacological transformation of traditional herbal medicines with processing. Evodia fruit (EF) has processed for the purpose of detoxification and reduction of its bitter taste. There are various methods of processing EF in Oriental medicinal reference. Among them, we processed EF according to the method of Sang-han theory, the most famous medicinal reference. We processed EF with washing in hot water, and then dried. Processed EFs(PEFs) were prepared according to the above procedure through repetition of 1,3,5 and 7 times respectively. The contents of weight loss, water extract, diluted ethanol extract, ether extract, total ash, acid insoluble ash, alkaloids and limonin in non-processed EF (NPEF) and PEFs were examined. The weight loss, and contents of water extract and dilute ethanol extract in PEF showed decrease in proportion to increase of washing time, while the contents of ether extract, total ash and acid insoluble ash showed little change as compared with those of NPEF. And the content of evodiamine and rutaecarpine was not changed distinctly. However, the content of limonin decreased in the final processed material in proportion to increase of washing times with hot water. And the intense of bitter taste in PEF was also reduced. These results were ascribed to the flowing-out of the water-soluble portion. The biological activities of NPEF and PEF were also investigated. In the test of DPPH scavenging effect, xanthine oxidase inhibition effect and TBA-Rs effect, PEF was more effective than NPEF in vitro. Also, both NPEF and PEF showed potent analgesic and anti-inflammatory effects against in mice. Especially, PEF by 3 times washing with hot water was more effective than other PEFs. From these results, it is considered that PEF should be prepared by 3 times washing with hot water.

• Korean Journal of Food Science and Technology
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• v.16 no.3
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• pp.358-362
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• 1984

Soybeans were soaked in water for 3 hrs and germinated at $25^{\circ}C$ for 5 days followed by hot water extraction and boilding for 30 min. The prepared soymilk was analyzed for chemical composition, phytic acid and soluble minerals. Germination resulted in a slow decrease in total solids while protein recovery increased to a maximum of 92.5% after 2 days. Carbohydrate content was reduced to 65% by the 5th day of germination. The intial phytic acid content in soymilk of 1.26g recovered from 100g dry soybean was decreased by 41.3% while inorganic phosphorus increased more than four times from 31.3mg to 135.0mg. Total soluble minerals was also steadily increased.