• Title/Summary/Keyword: acid soaking

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A Comparative Study on the Mechanical Properties of Plywood treated with Several Fire-Retardant Chemicals(II) - Effect of Platen Temperature in Press Drying on the Static Bending Strength of Treated Plywood - (수종(樹種) 내화약제(耐火藥劑)로 처리(處理)된 합판(處理)의 기술적(技術的) 성질(性質)에 관(關)한 비교연구(比較硏究)(II) - 열판건조시(熱板乾燥時) 열판온도(熱板溫度)가 처리합판(處理合板)의 휨강도(强度)에 미치는 영향(影響) -)

  • Chung, Woo-Yang;Kim, Jong-Man;Lee, Phil-Woo
    • Journal of the Korean Wood Science and Technology
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    • v.12 no.4
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    • pp.12-18
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    • 1984
  • Soaking treated in 20% aqueous solutions of $(NH_4)_2SO_4$, $NH_4H_2PO_4$, $(NH_4)_2HPO_4$, $Na_2B_4O_7-H_3BO_3$(60:40) and Minalith, the mixed salts for 9 hrs. the wet 3.5mm meranti (Parashorea spp.) plywoods were press-dried at 90, 120 and $150^{\circ}C$ and put to static bending test to examine the influence of redrying temperature on the strength of fire-retardant treated plywoods ill flexure. While water-soaking treatment (control) showed serious reduction in Stress at proportional limit, MOE, MOR, Work per unit volume at $150^{\circ}C$, all the fire-retardant treatments maintained bending strength even at $150^{\circ}C$ and showed rather increased values in case of some chemicals. In view of drying rate and maintenance of strength, the most pertinent platen temperature was $150^{\circ}C$ and Borax-Boric acid was the predominant fire-retardant in this study.

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Dietary Fiber in Godulbaegi(Korean Lettuce, Ixeris sonchifolia H.) Kimchi (고들빼기김치 식이섬유질의 식품학적인 특성)

  • Hong-Soo Ryu;Eun-Young Hwang;Soon-Sil Chun;Kun-Young Park
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.24 no.3
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    • pp.404-408
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    • 1995
  • The effect of processing conditions on the changes in the contents of dietary fiber fractions and its physical properteis of Godulbaegi(Korean lettuce, Ixeris sonchifolia H.) was determined during preparation and fementation for kimchi. Water holding capacity(WHC) and oil adsorption capacity(OAC) were also checked on the subject of freeze dried powder from different stages of the kimchi processing. Neutral detergent fiber(NDF) content in young samples(leaf and root) decreased with prolonged soaking and fermentation period. Every young samples had a higher level in NDF than in ripe samples. Noticeable decrease in acid detergent fiber(ADF) without a change in ripe roots was showed after fermentation($4^{\circ}C$, 60 days). The water holding capacity of freeze dried young plants ranged from 5.78ml/g for roots to 6.31ml/g for leaves. Soaking and fermentation resulted in decreasing WHC and about 50% of WHC(raw leaves) was lowered after kimchi fermentation($4^{\circ}C$, 40 days). OAC of all samples were lower than WHC in same samples significantly and those were also decreased after soaking and fermentations as WHC.

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Germination Induction of Some Weed Seeds Stored Under the Dry and Low Temperature Condition (건조저온저장(乾燥低溫貯藏)한 몇가지 잡초종자(雜草種子)의 발아유기(發芽誘起))

  • Cho, K.Y.;Kim, J.S.;Kim, Y.S.
    • Korean Journal of Weed Science
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    • v.7 no.1
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    • pp.19-28
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    • 1987
  • These experiments were conducted to recognize the germination change in relation to storage period, using 25 kinds of field-collected weed seeds stored under the dry and low temperature ($4{\pm}1^{\circ}C$), and to establish a simple germination induction methods in some kinds of them. No or weak dormancy was observed in Lepidium virginicum, Rumex japonicus, Cirsium japonicum var. ussuriense, Aeschnomene indica and Ludwigia prostrate. The germination of Digltaria sanguinalis, Portulaca oleracea, Amaranthus spp., Echinochloa crux-galli, Polygonum persicaria, Cyperus iria, and Aeschynnmene indica was enhanced by $H_2SO_4$ treatment for 20, 2, 2, 50, 40, 3 or 5 minutes, respectively. Favorable germination in Polygonum persicaria and Echinochloa crus-galli was obtained by soaking in water for 25 days and 50 days, respectively. Moisture treatment for 21 days and 14 days caused the enhancement of germination in Cyperus difformis and Aneilema keisak, respectively. Combination of various treatments in Cyperus iria was most effective when the seeds treated with $H_2SO_4$ for 3 minutes incubated in alternating temp. after soaking in 0.2% $KNO_3$, but their effect on Digitaria sanguinnlis was little.

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Comparative Study on the Control and Removal of Formaldehyde for the Urea-formaldehyde Resin Bonded Plywood -Adhesive control- (요소수지접착합판(尿素樹脂接着合板)의 유리(遊離)포름알데히드 방산(放散)제거 및 조절방법에 대한 비교연구(比較硏究))

  • Lee, Hwa-Hyoung
    • Journal of the Korean Wood Science and Technology
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    • v.9 no.3
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    • pp.16-23
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    • 1981
  • This study has been carried out to make a comparative study for the adhesive control methods specifically developed for application to formaldehyde. The method for formaldehyde determination used in this report is the improved chromo tropic acid determination. The results are summarized as follows: 1. The soaking treatment in aqueous solution of urea wok the most scavenging effect on the formaldehyde release from a plywood sample glued with a urea formaldehyde adhesive, and other removal treatment such as resorcinol, albumine-, and hardener-treatment gave significant reduction too. 2. In glue shear strength of dry test, 2% of resorcinol treatment and soaking treatment showed the highest strength and all the other treatment met the standard, but in hot water soaking test, 2% of resorcinol treatment gave the best results, on the other hand, adding the hardener showed the lowest strength and failed in meeting the standard. 3. Air dried moisture content of all treated plywood met the standard which calls for 13% or bellow. 4. In this comparative study, we can make a strong combination each other or go into the details of one treatment for the best result through the more study.

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Changes in Quality Characteristics of Meju Made with Germinated Soybean during Fermentation (싹튼 콩으로 제조한 메주의 발효기간에 따른 품질변화)

  • Choi, Ung-Kyu;Kim, Mi-Hyang;Lee, Nan-Hee;Jeong, Yeon-Shin;Hwang, Young-Hyun
    • Korean Journal of Food Science and Technology
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    • v.39 no.3
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    • pp.304-308
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    • 2007
  • This research was conducted to investigate the changes in quality characteristics of meju made with 24-hour germinated soybeans according to fermentation time. The study confirmed that the amino nitrogen content immediately after soaking was 15.5 mg%, and the content rapidly increased in the beginning of the germination process and continued to increase to 312.9 mg% by 48 hours of fermentation. The number of fungi in the whole soybean meju made with 24-hour germinated soybeans was higher than the numbers of bacteria and yeast since the Aspergillus oryzae was inoculated artificially. The content of organic acids, in which the amount of citric acid was highest followed by tartaric acid and malic acid, increased with the fermentation process. The level of free amino acids in the whole soybean meju made from the 24-hour germinated soybeans increased rapidly with fermentation. The free amino acid content after 48 hours of fermentation (2,513.5 mg%) was 5.7 times higher than the content of the soaked germinated soybeans. The content of glutamic acid was highest followed by aspartic acid, lysine, leucine, and proline. The ratio of glutamic acid to the total free amino acids at 48 hours fermentation was 21.2% for the whole soybean meju. It was confirmed that the total isoflavone content, in which the content of genistein was highest followed by daidzein and glycitein, increased at the beginning of the fermentation process, but did not change thereafter.

Changes in Free and Bound Forms of Bioactive Compound Profiles of Adzuki Bean with Germination (발아에 따른 팥의 유리형 및 결합형 기능성분 변화)

  • Kim, Min Young;Jang, Gwi Yeong;Oh, Nam Seok;Baek, So Yune;Kim, Kil Ho;Kim, Kyung Mi;Kim, Hongsik;Lee, Junsoo;Jeong, Heon Sang
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.8
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    • pp.937-943
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    • 2017
  • This study was performed to investigate the changes between free and bound forms of bioactive compounds in germinated adzuki bean. Adzuki bean was germinated at $25^{\circ}C$ for 6 days, and then free and bound forms of bioactive compounds were extracted. Total free polyphenol and flavonoid contents in of raw adzuki bean increased from 0.91 mg/g and 0.60 mg/g in before germination to 2.37 mg/g and 3.03 mg/g in at 6 days after germination, respectively. Bound polyphenol, flavonoid, and phenolic acid contents also increased with increasing germination periods, whereas bound polyphenol and flavonoid contents slightly reduced in at 2 days after germination. The total phenolic acid contents, including ferulic acid, veratric acid, hesperidin, salicylic acid, naringenin, and hesperidin, increased during germination, and germination process can convert compounds to phenolic acid via anabolism and catabolism. Total anthocyanin and anthocyanidin contents of adzuki bean decreased during germination due to hydration by water during soaking or enzyme activation of anthocyanase during germination. These results suggest that the germination process increased utilization of functional compounds such as phenolic compound and isoflavones in black soybean.

Bacterial Reverse Mutation Test Evaluation of Hydrolyzed GMP Powder Containing Highly Concentrated Sialic Acid (23%) produced by Enzyme Separation and Solvent Enrichment Method (효소분리 및 용매정제법으로 제조한 고농도 Sialic Acid(23%)가 함유된 GMP 가수분해분말의 미생물복귀돌연변이시험 연구)

  • Kim, Hee-Kyong;Cho, Hyang-Hyun;Noh, Hye-Ji
    • Journal of Dairy Science and Biotechnology
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    • v.34 no.2
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    • pp.91-98
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    • 2016
  • The goal of this study was to develop hydrolyzed whey protein powder (23%-GNANA) manufactured with high content of sialic acid, a marker compound that is usually present at 7% concentration in GMP obtained from the milk protein. It is a safe food, used worldwide in infant and baby foods, etc. The test substance was prepared using (7% sialic acid containing) GMP as a raw material. Alcalase, an enzyme approved as a food additive, was used after separating sialic acid, with 100% efficiency, and 23%-GNANA (composed of 23% sialic acid and protein; product name: HELICOBACTROL-23), provided by MEDINUTROL Inc. (Korea), manufactured to have high (23%) content through ethanol soaking and enrichment. Bacterial reverse mutation (Ames) test was conducted in accordance with the GLP Guideline using the test substance specified above. To detect its mutagenicity potential in microorganisms, histidine auxotrophic strains of Salmonella typhimurium, TA98, TA100, TA1535, and TA1537, and tryptophan auxotrophic Escherichia coli strain, WP2uvrA, were used. The bacterial reverse mutation (Ames) test was performed using five concentrations of the test substances (0, 61.7, 185, 556, 1,670, $5,000{\mu}g/plate$). The evaluation did not reveal repetitive increase of colony generating values and positive criteria for reverse mutagenicity for any tested concentration in the five strains regardless of the presence of metabolic activation system, and no dose-dependency. In conclusion, the safety of 23%-GNANA test substance was verified by the bacterial reverse mutation test conducted before registration of 23%-GNANA as a food additive.

Color Characteristics of Korean Traditional Soy Sauces Prepared Under Different Processing Conditions (제조조건에 따른 한국전통간장의 색 특성에 관한 연구)

  • 전민선;손경희;채선희;박현경;전형주
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.1
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    • pp.32-38
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    • 2002
  • The characteristics of blown color of Korean traditional soy sauces under different processing conditions were investigated in this research. As for meju type, traditional and modified mejus were used. The samples were produced from four levels of aging time. 0 day, 60 days, 120 days and 180 days in both clay jar and glass jar. Color intensity of soy sauce was probed with different mothods. In terms of colorcharacteristics, the absorbance at 420 nm seemed to reflect the brown color intensity of soy sauces. UV-VIS spectra of the soy sauce with traditional meiu revealed that the absorbance at 235 nm was produced during the soaking period whereas that at 410 nm was created during the aging process and only round in the spectra of soy sauce aged for 180 days. As for the soy sauce with modified meiu, the maximum absorbance was focused at 235 nm which were prepared during soaking period.

Stability Evaluation of Cleaning Agent for Ceramics (토기 및 도자기 유물에 사용되는 보존처리용 세척제의 안정성 평가)

  • Park, Daw-Woo;Kang, Hyun-Mi;Nam, Byeong-Jik;Jang, Sung-Yoon
    • Journal of Conservation Science
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    • v.25 no.4
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    • pp.451-464
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    • 2009
  • To do conservation for ceramics, sometimes it needs to clean the ceramics chemically to remove stains on the ceramics, which should be performed with caution. This study will provide quantitative data about the extraction characteristics of major elements from ceramics through the soaking test to evaluate the stability of ceramic cleaning agents. As soft textured pottery(fired at $700^{\circ}C$) had high absorption, it showed higher extraction characteristics in short soaking time. Especially the strong acid among chemical cleaning agents caused the expoliation and the color change on the surface of soft textured pottery. But these color change had no effect on the physical characteristics of soft textured pottery. The hard textured pottery(fired at $1,000^{\circ}C$) is relatively stable in the cleaning agent because it is ascertained the extraction of that was not enough and also it had little chromatic and physical change by strong acid. Porcelains(Celadon, Whiteware and Puncheong ware) was safer than the soft textured pottery due to their low extraction. But it should take precautions to clean the porcelains with lots of cracklewares such like Puncheong ware chemically in connection with the extraction characteristics and their cracklewares.

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Bacterial Community Migration in the Ripening of Doenjang, a Traditional Korean Fermented Soybean Food

  • Jeong, Do-Won;Kim, Hye-Rim;Jung, Gwangsick;Han, Seulhwa;Kim, Cheong-Tae;Lee, Jong-Hoon
    • Journal of Microbiology and Biotechnology
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    • v.24 no.5
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    • pp.648-660
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    • 2014
  • Doenjang, a traditional Korean fermented soybean paste, is made by mixing and ripening meju with high salt brine (approximately 18%). Meju is a naturally fermented soybean block prepared by soaking, steaming, and molding soybean. To understand living bacterial community migration and the roles of bacteria in the manufacturing process of doenjang, the diversity of culturable bacteria in meju and doenjang was examined using media supplemented with NaCl, and some physiological activities of predominant isolates were determined. Bacilli were the major bacteria involved throughout the entire manufacturing process from meju to doenjang; some of these bacteria might be present as spores during the doenjang ripening process. Bacillus siamensis was the most populous species of the genus, and Bacillus licheniformis exhibited sufficient salt tolerance to maintain its growth during doenjang ripening. Enterococcus faecalis and Enterococcus faecium, the major lactic acid bacteria (LAB) identified in this study, did not continue to grow under high NaCl conditions in doenjang. Enterococci and certain species of coagulase-negative staphylococci (CNS) were the predominant acid-producing bacteria in meju fermentation, whereas Tetragenococcus halophilus and CNS were the major acid-producing bacteria in doenjang fermentation. We conclude that bacilli, LAB, and CNS may be the major bacterial groups involved in meju fermentation and that these bacterial communities undergo a shift toward salt-tolerant bacilli, CNS, and T. halophilus during the doenjang fermentation process.