• Title/Summary/Keyword: amino alcohol

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Gelation Behavior of Ultra High Temperature Pasteurized Milk during Storage (초고온 살균유의 저장 중 겔 형성 거동)

  • 조영희;홍윤호
    • Food Science of Animal Resources
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    • v.20 no.1
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    • pp.8-14
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    • 2000
  • In order to examine physicochemical gelation behavior of ultra high temperature(UHT) pasteurized milk during storage at 4$^{\circ}C$ and 25$^{\circ}C$, pH, electrophoresis, alcohol test, sialic acid contents and free amino groups contents were biweekly determined. The pH of UHT pasteurized milk decreased with increasing storage time. Gelation of the UHT milk occured faster at 25$^{\circ}C$ than at 4$^{\circ}C$ with larger decreasing rate of pH. The alcohol test showed positive results at lower pH than 6.5, which could indicate the casein instability and beginning of gelation. The electrophoretic patterns showed a decrease in the concentrations of all caseins. Degradation of k-casein was faster in all cases, while $\alpha$-casein and $\beta$-casein were also extensively degraded later. The sialic acid contents of the samples increased gradually during storage, and the increasing rate was higher before gel formation. The free amino groups of the samples increased gradually during storage. The increasing rate of free amino groups was faster at 25$^{\circ}C$ than at 4$^{\circ}C$. The samples stored at 25$^{\circ}C$ gelled earlier than those stored at 25$^{\circ}C$, with corresponding increase of free amino groups. The residual proteolytic enzymes, which survived during the UHT heat treatments and were reactivated during storage, could be responsible for UHT pasteurized milk gelation during storage. It is assumed that proteolytic degradation of caseins followed by aggregation would be attributable to complicated reaction mechanism.

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Direct Organocatalytic Regioselective α-Hydroxyamination of α-Branched Aldehydes

  • Kim, Sung-Gon;Ahn, Eun-Ju;Park, Tae-Ho
    • Bulletin of the Korean Chemical Society
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    • v.28 no.10
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    • pp.1665-1669
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    • 2007
  • A direct regioselective α-hydroxyamination of α-branched aldehydes with nitrosobenzene using cis-5-benzylproline as catalyst has been developed for the preparation of α-hydroxyamino aldehydes possessing a quaternary carbon center. Such compounds are versatile building blocks for the synthesis of quaternary α- amino acids, β-amino alcohols, and 1,2-diamines.

The Interaction of Chiral Amino Thiols with Organozinc Reagents and Aldehydes: A Mechanism of Amino Thiol-Catalyzed Addition of Organozinc Reagents to Aldehydes

  • 강자효;김진범;김지영;이덕환
    • Bulletin of the Korean Chemical Society
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    • v.19 no.4
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    • pp.475-481
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    • 1998
  • Details of various equilibria involved in the reactions of oxaza- and thiazazincolidine catalysts, generated from either β-amino alcohol or β-amino thiol, with aldehyde were studied by colligative measurements. The results indicated that the coordination of diethylzinc prior to the coordination of aldehyde is essential for high enantioselectivity of the thiol catalyzed reaction. The probable origin of asymmetric nonlinearity is also presented.

Studies on the Nitrogen Metabolism of Soybeans -II. Variation of Free Amino acids during the Growth of Younger Plants (대두(大豆)의 질소대사(窒素代謝)에 관(關)한 연구(硏究) -II. 유(幼) 식물시기(植物時期)에서의 유리(遊離)아미노산(酸)의 소장(消長))

  • Kang, Y.H.
    • Korean Journal of Soil Science and Fertilizer
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    • v.3 no.1
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    • pp.49-54
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    • 1970
  • In an effort of determine the metabolism and bio-synthesis of nitrogen, was studied at variance of souble nitrogens, free amino acids and total alcohol soluble amino acids during the growth of younger soybean plants, and saybean divides into cotyledon and embryonic organ (shoot and root system) in this experiment. 1. In the soluble nitrogen of soybean, ratio of increase and decrease in the amino acids of them was displayed the near phenomena both cotyledon and embryonic organ of soybean. But, in the 17th days after seed germination, that is the developmeatal stage of adult leaf of soybeans, was appear the maximum value. It has been suggested that the stage of first half period of growth as boundary the stage of adult leaf development which indicated clear morphologically, at the younger soybean plants, is the step that nitrogen assimilation. 2. It was investigated the amino acids of seventeen kinds in the seed state, but at the third days after seed germination, was investigated the amino acids of nineteen kinds. Ultimately, it appears the translocation from cotyledon to embryonic organ in the distribution of amino acid, the nineth day which differentiation begining day of embryonic organ, then after, it happen the variation of number of inspected amino acid in the cotyledon and embryonic organ but only the variance changes in the distribution and quantitative aspects. Especially, the most conspicuous fact was indicated the accumulation of Asparagine, that is the phenomena of Asparagine-accumulation was constitute, not with standing no fertilization from outside. It may be concluded from the results of this investigation that the difference of special phenomena of soybean from the embryo of other plans. 3. In the initial stage of differentiation at embryonic organ number of inspected amino acid was very few, and then, it was slightly appeared the increase-phenomena in the number of them. It was that the amino acid inspecting the initial stage was translocated from the cotyledon. It is suggested that the intermediate-metabolism of amino acid was constituted on the basis of above the result. 4. The phenomena of increase and decrease of total alcohol soluble amino acid were essentially identical to the water soluble amino acid of soybean, but it was appeared the severe difference of amounts in both of them.

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Flavour Improvement of Soybean Pastes by the Addition of Bacillus licheniformis and Saccharomyces rouxii (Bacillus licheniformis 와 Saccharomyces rouxii 첨가에 의한 된장의 풍미향상)

  • Shin, Soon-Young;Kim, Young-Bae;Yu, Tae-Jong
    • Korean Journal of Food Science and Technology
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    • v.17 no.1
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    • pp.8-14
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    • 1985
  • In order to give the unique flavour of traditional Doenjang (Korean-style soybean paste) to commercially manufactured soybean paste, the addition of Bacillus licheniformis and Saccharomyces rouxii was tried and their influences were investigated. The addition of B. licheniformis and S. rouxii in soybean paste decreased the content of reducing sugars. By the addition of B. licheniformis, the contents of amino type nitrogen and titrable acidity were increased. The content of ammoniacal nitrogen was reduced and ethyl alcohol production was increased by the addition of S. rouxii. The viable counts of molds showed the decreasing tendency during the aging and it was accelerated by the addition of B. licheniformis and S. rouxii. Acetaldehyde, acetone, ethylacetate, methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol and isopropyl alcohol were detected from the vapor of all tested ripen soybean pastes, while in a traditional Doenjang, isoamyl alcohol and isobutyl alcohol were not. The B. licheniformis and S. rouxii added sample showed richest free amino acid content. In organoleptic test the B. licheniformis and S. rouxii added sample showed the most excellent overall acceptability.

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The Dietary Intake and Nutritional Status of Fatty Liver Patients (지방간 환자의 식품섭취 및 영양상태에 관한 조사-남성을 중심으로-)

  • 이석화;기춘석;장유경
    • Korean Journal of Community Nutrition
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    • v.3 no.4
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    • pp.622-629
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    • 1998
  • This study was performed to investigate the effect of dietary intakes and nutritional status for fatty liver male patients with fatty livers. General characteristics, nutritional knowledge, and dietary intakes were obtained from fatty liver male patients aged 20-60yr living in Seoul and Kyunggi province by individual interview and blood samples. The Results were as follows : the mean age of the subjects was 39yrs. Old and over half the subjects were overweight. Although nutritional knowledge, recognition, and accuracy scores were good, these did not affect the subject's health. The average alcohol intake of subjects was 79.8g/day and the drinking duration was 5-40yrs(average : 17yrs). The subjects drank alcohol over 4tiles/week and preferred Soju. Most side dishes taken with alcohol drinking by the subjects were foods from animal sources. Half of the subjects also drank alcohol the next day for breakfast as a hangover-chaser. The reasons for drinking were due to social relationships and by habit. Vitamin D and folate were lower than the RDA for Koreans, and other nutrient amounts were higher than the RDA. The amounts of aspartate amino-transferase(AST), Alanine amino-transferase(ALT), ${\gamma}$-glutamyl transpeptidase(${\gamma}$-GTP), Triglyceride(TG) for the subjects were higher. In conclusion, fatty liver patients drank excessively and frequently. It seems that heavy alcohol drinking is more prone to overweight or obese people and contributes to fatty livers. Therefore, the subjects need to be taken effectively educated about alcohol-induced liver damage and the importance of a balanced diet for on healthy liver.

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Enantioselective Recognition of Amino Alcohols and Amino Acids by Chiral Binol-Based Aldehydes with Conjugated Rings at the Hydrogen Bonding Donor Sites

  • Kim, Ji-Young;Nandhakumar, Raju;Kim, Kwan-Mook
    • Bulletin of the Korean Chemical Society
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    • v.32 no.4
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    • pp.1263-1267
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    • 2011
  • Novel binol-based uryl and guanidinium receptors having higher ring conjugation at the periphery of the hydrogen bonding donor sites have been synthesized and utilized to study the enantioselective recognition of 1,2-aminoalcohols and chirality conversion of natural amino acids via imine bond formation. There is a remarkable decrease in the stereoselectivites as the conjugation increases at the periphery of hydrogen bonding donor sites. The guanidinium-based receptors show more selectivity towards the amino alcohol than that of the uryl based ones due to its charge reinforced hydrogen bonds. The conversion efficiency of L-amino acids to Damino acids by the uryl-based receptors is higher than that of the guanidinium-based ones.

Alcohol Dehydrogenase Activity and Sensory Evaluation of Hutgae (Hovenia dulcis Thunb) Fruit Soy Sauce (헛개열매 간장의 알코올 분해 활성 및 관능적 품질 특성)

  • Jung, Su-Young;Lim, Jung-Sup;Song, Hee-Sun
    • The Korean Journal of Food And Nutrition
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    • v.25 no.4
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    • pp.747-754
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    • 2012
  • The objective of this study was to investigate free amino acid composition, antioxidant activity, alcohol dehydrogenase activity and the sensory quality attributes for the development of functional soy sauce using Hutgae (Hovenia dulcis Thunb) fruit, which is well-known for improving liver function and alleviating various negative physiological effects following heavy consumption of alcoholic beverages. Soy sauces adding six types of extract from Hutgae fruit (HF) were prepared (SSH1: HF 20%, SSH2: HF 10%, SSH3: HF 20%/40 days NaCl extract, SSH4: HF 20%/20 days NaCl extract, SSH5: HF 20% water bath extract, SSH6: freeze-drying powder from HF 20% aqueous extract), compared with soy sauce using the conventional method. These soy sauces were used for determining alcohol dehydrogenase activity by NADH absorbance, the antioxidant effect by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and sensory evaluation by sensory scaling. Total free amino acid contents for most samples were in the range of 327.3 to 375.5 mg%, and then, aspartic acid and glutamic acid content of SSH1 and SSH5 were higher than that of others. DPPH radical scavenging activity was shown to be the highest in SSH4, also SSH1, SSH5 and SSF6 were shown to be higher than the control group. Alcohol dehydrogenase activity was shown to be the highest in SSH5. In sensory evaluation, the highest intensity of roast smell was observed in SSH4 while sweet taste was shown to be the highest in SSH5, and SSH3 and SSH5 revealed higher overall acceptability. From these results, Hutgae fruit soy sauces demonstrated antioxidant activity and alcohol dehydrogenase activity. In conclusion, soy sauces containing the water bath extract of Hutgae fruit may be used as a functional seasoning.

Continuous rapid Production of Soy Sauce by Coimmobilized Mixed Culture system of Zygosaccharomyces rouxii and Candida versatilis using Air Bubble Column Reactor (Zygosaccharomyces rouxii와 Candida versatilis의 동시 고정화에 의한 Air Bubble Column Reactor에서 간장의 연속적 속성 생산)

  • 류병호
    • KSBB Journal
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    • v.18 no.6
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    • pp.455-460
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    • 2003
  • This study was designed to find out the rapid fermentation of soy sauce from koji hydrolyzates using air bubble column reactor packed with coimmobilized mixed culture system. Continuous ripid production was performed by coimmobilized Z. rouxiii BH-90 and C. versatilis BH-91. Coimmobilized cells of Zygosaccharomyces rouxii BH-90 and Candida versatilis BH-91 mixture cells in the column reactor produced 2.8% ethyl alcohol and 18mg/L 4-ethylguaiacol over 96 hours under the optimal conditions. Coimmobilized cells produced 2.30∼2.4% ethyl alcohol during 30 days, and decreased gradually from 40 days to 70 days. Also coimmobilized cells produced 4-ethylguaiacol at the constant rate of 16∼18mg/L and decreased gradually after 40 days. Final product of soy sauce contained 2.4% ethyl alcohol and 18mg/L 4-ethylguaiacol. However, amino acid compositions of soy sauce were consisted of predominantly glutamic acid, leucin, arginine, aspartic acid, Iysine and valine, which were more than 50% of total amino acid.