• Title/Summary/Keyword: acid content

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Enhancement of Mechanical Properties of 2K Polyurethane Adhesives via Forming Ionic Bonds (이온결합 형성에 따른 이액형 폴리우레탄 접착제의 기계적 특성 향상)

  • Kwon, Haeun;Kim, Doo Hun;Kim, Gu Ni
    • Journal of Adhesion and Interface
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    • v.22 no.4
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    • pp.128-135
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    • 2021
  • In this study, the acid polyols containing acid groups were synthesized, the novel polyurethane adhesive was developed by introducing the acid polyol by content. The acid polyols were introduced, the mechanical properties showed the maximum value when the acid content was 0.1 to 0.3 wt%, and it was confirmed that the mechanical properties and adhesive strength decreased at the content higher than 0.5 wt%. As the acid group, carboxylic acid and sulfuric acid were introduced to compare properties, and carboxylic acid showed stronger hydrogen bonding potential than sulfuric acid and improved mechanical properties. In addition, the correlation between particle size and mechanical properties was confirmed by introducing ZnO and CaCO3. When ZnO and CaCO3 were introduced, an ionic bond was formed with an acid group, and it was confirmed that mechanical properties were increased.

Optimization of the Vinegar Fermentation Using Concentrated Apple Juice (농축 사과주스를 이용한 식초 발효조건의 최적화)

  • 서지형;이기동;정용진
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.3
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    • pp.460-465
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    • 2001
  • To prepare vinegar using concentration apple juice, response surface methodology (RSM) was applied to optimize and monitor the vinegar fermentation properties by two stage fermentation. In the first stage, the optimum conditions for maximum alcohol contents were 18.56。Brix of initial sugar concentration, 61.96 rpm of agitation rate and 67.32 hr of fermentation time. The optimum condition for maximum acidity in the second stage (vinegar fermentation) were 201.53 rpm of agitation rate and 179.42 hr of fermentation time. Malic acid content was the highest and its content little changed during acetic acid fermentation. Lactic acid content increased a little during alcohol fermentation. Acetic acid content apparently increased during acetic acid fermentation.

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Effects of Antler Development Stage on Fatty acid, Vitamin and GAGs Contents of Velvet Antler in Spotted Deer (Cervus nippon)

  • Lee, S.R.;Jeon, B.T.;Kim, S.J.;Kim, M.H.;Lee, S.M.;Moon, S.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.10
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    • pp.1546-1550
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    • 2007
  • This study aimed to provide basic information as the foundation for further studies on the assessment of velvet antler quality by investigating the changes in fatty acid, vitamin A and E, minerals and GAGs contents by development stage of antler in spotted deer (Cervus nippon). Twelve stags (aged 4 to 5 years) were divided into two groups and velvet antler harvested 40 days (FDG) and 60 days (SDG) after casting of the buttons from the previous set. Total saturated fatty acid was lower in FDG than SDG (p<0.05). Total monounsaturated fatty acid, conjugated linoleic acid (p<0.05), polyunsaturated fatty acid and ${\omega}$3 fatty acid were higher in FDG than SDG. The vitamin A content of FDG was higher than that of SDG, but the vitamin E content of FDG was lower than that of SDG (p<0.05). SDG had significantly higher calcium and phosphate content than FDG (p<0.05). The magnesium content showed a similar trend to the contents of calcium and phosphate, but there was no significant difference between SDG and FDG. Uronic acid content was higher in FDG than SDG but there was no significant difference. The contents of GAGs and sialic acid were significantly higher (p<0.05) in FDG than SDG. These results indicated that the longer stage of antler development had lower content of activating components and this lead to a decrease of antler quality.

Degradation of Ascorbic acid in Limited Dissolved Oxygen Environment (제한된 산소 존재중의 Ascorbin 산의 분해에 대하여)

  • Rhee, Sook-Hee
    • Journal of Nutrition and Health
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    • v.9 no.4
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    • pp.54-58
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    • 1976
  • Deterioration of ascorbic acid content is the important factor in the food quality. The degradation of ascorbic acid undergoes as a first-order of reaction in the presence of excess oxygen content. However, under the limited oxygen content, ascorbic acid decomposes as a psudo-first order of reaction. The ascorbic acid, in this study, under the limited dissolved oxygen content in the presesce of iron(III) and copper(II) decomposed as first-order reaction with a little influence in rate constant and the light was an accelerating factor on the ascorbic acid degradation.

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Seed Protein Content and Fatty Acid Composition of Soybeans collected from Southwestern Islands in Korea

  • Kwon, Byung-Sun;Shin, Jeong-Sik;Choi, Seong-Kyu
    • Plant Resources
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    • v.5 no.3
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    • pp.181-186
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    • 2002
  • The 129 soybean genotypes were collected in 43 island locations from January to May 2001. Seeds of 129 genotypes collected were analyzed for crude protein and fatty acid composition contents. The crude protein content was averaged to 41.1 % and ranged from 37.4% to 44.4%. The average palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid content were 12.0%, 4.0%, 23.2%, 55.5%, and 7.9%, and the ranges of those were 10.0% to 15.0%, 3.0% to 4.8%, 21.7% to 25.5%, 50.2% to 58.3% and 7.0% to 12.0%, respectively. Heritabiliries of palmitic acid, oleic acid, linoleic acid, and crude protein were higher, but that of stearic acid and linolenic acid were relatively lower. The genotypic correlation coefficients between crude protein and oleic acid showed highly positive correlation, but that of linoleic acid showed highly opsitive correlation, but that of linoleic acid showed highly negative correlation and also palmitic acid, stearic acid and linolenic acid showed negative correlation.

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Chemical Components Related with Seed Dormancy and Viviparous Germination in Rice (벼 종실의 휴면 관련 성분과 휴면성 및 수발아성과의 관계)

  • 김용욱
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.40 no.1
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    • pp.113-119
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    • 1995
  • This excperiment was conducted to investigate relation on seed dormancy and vi-viparous germination with sucrose content, fatty acid composition and abscisic acid content of rice seeds. The following results were obtained by this experiment. Sucrose content of brown rice harvested at 20 and 40 days after heading was higher in Japonica and Sare type varieties than in Tongil and Indica type rices. Positive relationship was found be-tween sucrose content of brown rice and viviparous germination rate of rice varieties tested.J aponica and Sare type rice varieties showed low proportion of oleic acid and higher proportion of linoleic acid in brown rice harvested at 20 and 40 days after heading than Tongil and Indica rices tested. Viviparous germination was negatively correlated with the proportion oleic acid and positively with that of linoleic acid. Abscisic acid content in hull of rice seeds stored for 30 days at 25/15$^{\circ}C$ fluctuation temperature condition was decreased more rapidly than 4$^{\circ}C$, and Japonica varieties tested showed lower con-tent of abscisic acid in rice hull than Tongil and Indica varieties used.

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Chemical compositions of Lentinula in growth stage - A study on application plan of Lentinula I - (표고버섯의 생육시기별 성분분석 - 표고버섯의 활용방안 연구 I -)

  • 조덕봉;현규환;나광출;최지호;서재신;강성구;김용두
    • Korean Journal of Plant Resources
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    • v.15 no.2
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    • pp.128-134
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    • 2002
  • Content of crude protein in both pileus and stalk increased progresively as growth period became longer and then decreased at old stage. Contents of ash and reducing sugars followed the same trend as that of the crude protein. However, content of crude lipid decreased as growth progressed more. Seventeen kinds of amino acid were detected in Lentinula. Content of total amino acid increased as mushroom grew more, but decreased after old stage. The amino acid such as Glu, His, Gly and Ala were contained with relatively large amount in Lentinula. Content of free amino acid showed the similar trends as that of total amino acid. Contents of most of the mineral increased as growth period progressed, but K content decreased as growth period became longer. Contents of K and P were much higher than contents of other mineral. The major fatty acid contained in Lentinula were linoleicacid, palmitic acid and oleic acid. The large amount of volatile component in Lentinula was 1-octen-3-ol, so that this material was speculated to be major source of perfume. Other perfumic materials such ethyl acetate, 3-octanone, ethanol, (E)-2-octenal, 4-octen-3-one, acetaldehyde, ethyl formate were also contained in Lentinula, especially in pilous.

Morphological characters, Total phenolic content, and Fatty Acid Compositions of Safflower (Carthamus tinctorius) Genetic Resources

  • Awraris Derbie Assefa;Young Jee Kim;Ae-Jin Hwang;Bich-Saem Kim;Jae-Eun Lee
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2020.08a
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    • pp.94-94
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    • 2020
  • Safflower, a draught and salt tolerant oil seed crop of Compositae family, has been cultivated around the world mainly as source of edible oils and dyes, where India, the USA, Mexico, Australia, and Ethiopia contributing about 85% of the production altogether. In this study we have characterized some selected morphological properties of safflower plant and determined the the total phenolic content (TPC) and fatty acid composition in seeds of 237 genetic resources. All the seed coats were white colored while the petals had red, yellow and white pigments. The yellow was the predominant petal color being recorded in 182 accessions followed by red occurring in 49 accessions. The petal color of 47 of the accessions changed with development while the 190 accession showed no change of color. The leaves are ovate to obovate, mostly with dentate (21 moderate and 205 weak) and few smooth (11) margins. The plant length, leaf length, and leaf width were ranged between 65.7 and 160.8 cm, 14.3 and 37.0 cm, and 3.3 and 12.1 cm, respectively. The TPC was determined using Folin-Ciocalteu method and fatty acid compositions were evaluated using gas chromatography. The TPC content ranged from 23.71 to 132.72 µgGAE/mg dried extract (DE). The seeds of safflower genetic resources accounted an average crude fat content of 26.25% (14.84 to 41.70%). The total fatty acid is mainly comprised of 71.72% linoleic acid (18:2) and 20.08% oleic acid (18:1) on average, the remaining palmitic acid (16:0), stearic acid (18:0) and linolenic acid (18:3) contributing 5.84, 2.23 and 0.15 %, respectively. The fatty acid composition of safflower seeds has shown great variability, where oleic and linoleic acid have a wide range of variation, from 9.23 to 83.35% and from 10.46 to 82.62%, respectively

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Effects of Cooking and Drying Methods on the Lipid Content and Neutral Lipid Composition of Shrimp (가열 및 건조방법이 새우의 지방질 함량과 중성지방질 조성에 미치는 영향)

  • Kim, Hyun-Ku;Hawer, Woo-Derck S.;Shin, Hyo-Sun
    • Korean Journal of Food Science and Technology
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    • v.21 no.1
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    • pp.17-24
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    • 1989
  • Effects of cooking and drying methods on the lipids content and neutral lipid component of shrimp, Metapenaeus joyneri, were investigated. Total lipid content of the fresh shrimp was 6.0%(dry basis), which was not changed significantly depending on the cooking and drying methods. Lipid of the fresh shrimp was composed of 36.8% of neutral lipids, 21.5% of glycolipids, and 41.7% of phospholipids. Freeze dried shrimp was substantially higher in neutral lipid contents but lower in glycolipid and phospholipid contents than hot air dried one. Main components of the neutral lipids were triglycerides, free sterols, free fatty acids and esterified sterols. Freeze dried shrimp contained higher triglycerides contents than hot air dried shrimp, whereas free fatty acids content in hot air dried shrimp was greater than that of freeze dried one due to the decomposition of triglycerides to free fatty acids during hot air drying. Major fatty acid composition of the total lipid were palmitoleic acid, eicosapentaenoic acid and docosahexaenoic acid, and that of neutral lipid were palmitic acid, palmitic acid, oleic acid, eicosapentaenoic acid and docosahexaenoic acid in fresh shrimp.

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Effects of Addition of Citron Peel Powder on the Proximate Composition, Minerals, Vitamin A, C content and Fatty Acid Composition of Emulsion-type Sausage (유자과피 분말 첨가가 유화형 소시지의 일반 성분, 무기물, 비타민 A, C 함량 및 지방산 조성에 미치는 영향)

  • Lee, Jae-Ryong;Jung, J.D.;Hah, Y.J.;Lee, J.W.;Lee, J.I.;Lee, J.D.;Park, G.B.;Kwck, S.J.
    • Journal of Animal Science and Technology
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    • v.47 no.1
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    • pp.99-106
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    • 2005
  • This study was carried out to investigate the effects of addition of citron peel powder(OJ 0/0, 0.60/0, 0.9 %) on proximate composition, minerals, vitamin A, C content and fatty acid composition of emulsion-type sausages. The moisture content of sausage containing 0.3% citron peel powder were significantly(P< 0.05) higher compared to those for control. The crude fat content of sausage containing citron peel powder were significantly( P< 0.05) lower compared to those for control. The crude ash content of sausage containing 0.9% citron peel powder were significantly(P< 0.05) higher compared to those for control. The minerals, vitamin A and C content of sausage containing citron peel powder were significantly(P < 0.05) higher compared to those for control. The palmitic acid(CI6: 0) and linoleic acid(CI8: 2) content of sausage containing citron peel powder were higher compared to those for control, but the palmitoleic acid(CI6: I) content of sausage containing 0.9% citron peel powder were lower. The total saturated fatty acid content of sausage containing 0.3% citron peel powder were significantly(P < 0.05) lower compared to those for control.