• 한국축산식품학회지
• /
• 제20권1호
• /
• pp.8-14
• /
• 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.

• 한국식품저장유통학회지
• /
• 제7권3호
• /
• pp.278-284
• /
• 2000

한국산 인공재배 천만의 동결건조 분말은 수분 2.12%, 조단백질 4.41%, 조지방 1.20%, 조회분 2.25%, 조섬유 4.60%, 무질소물 85.15%로 분석되었다. 환원당 함량은 2.66%였으며 유리당은 glucose 13.14mg/g, sucrose 10.81mg/g, fructose 8.69mg/g 함유되어 있었다. 지방산은 11종이 검출되었으며 포화지방산이 18.69%, 불포화 지방산이 81.31%였으며 포화 지방산으로는 palmitic acid가 11.55%, 불포화 지방산으로는 linoleic acid가 63.13%로 가장 높았다. 그 외 불포화 지방산으로는 cis-5,8,11,14,17-eicosapentaenoic acid가 6.42%, linolenic acid가 4.33%를 차지하였다. 유기산으로는 oxalic acid, citric acid, malic acid, succinic acid, fumaric acid 등이 분리되었고 succinic acid의 함량이 1,238mg%로 가장 높았고 다음은 citric acid, malic acid, oxalic acid, fumaric acid의 순이었다. 분리된 18종의 총 아미노산중 aspartic acid가 522.8mg%로 가장 높은 함량을 차지했으며 taurin, hydroproline, alanine, threonine등이 존재했으며 taurin, hydroproline, alanine, threonine등이 존재하였다. 39종의 유리 아미노산 중 arginine이 15.01mg%로 가장 함량이 높았으며 asparagine, proline, sarcosine 순이었다. 총 페놀의 함량은 821.4mg%이었고 조사포닌의 함량은 3,738mg%를 나타내었다. 수용성 비타민으로는 ascorbic acid가 6.40mg%, 비타민 B1이 1.23mg%, 비타민 B2가 1.74mg% 함유되어 있었으며 지용성 비타민으로는 비타민 A가 1.22mg%, 비타민 E는 0.32mg%로 미량 함유되어 있었다.

• 한국수산과학회지
• /
• 제37권5호
• /
• pp.366-371
• /
• 2004

Powder and liquid products of the seasoned and smoked fish were manufactured with small-sized skipjack tuna (Euthynus pelamis) captured in the East Sea, Korea. The property changes of nucleotides and their related compounds, amino acid, and sensory attribute during storage were analyzed. IMP content was the highest among the nucleotides and their related compounds followed by inosine in both powder and liquid products. Nucleotides and their related compounds of the powder product increased slightly as storage period increased, while those of liquid product were constant. Glutamic acid $(15.6{\%})$, aspartic acid $(10.7{\%})$, and lysine $(9.3{\%})$ were major amino acids of the power product, while histidine $(36.2{\%})$ and taurine $(10.6{\%})$ were high in the liquid product. Free amino acid contents of liquid product increased during storage periods. There was no significant difference In the concentration of nucleotides and their related compounds, and composition of free amino acid between the products with/without liquid smoke. Aroma and acceptance were good in both products, while bitterness and sweetness were poor.

• 한국식품영양학회지
• /
• 제11권2호
• /
• pp.249-255
• /
• 1998

경북 동해안 일대의 전통 향토식품인 꽁치 과메기의 건조방법을 자연건조와 인공건조로 달리하여 각각 15일 건조기간 중의 핵산 관련물질, 아미노산 함량의 변화를 조사하였다. 핵산 관련 물질은 건조기간 중 ADP, AMP 함량은 서서히 감소한 반면 IMP함량은 증가하여 IMP 축적현상을 보였으며 건조기간 중 inosine과 hypoxanthine의 함량이 증가하였다. K value의 변화는 건조과정 중 점차 증가하여 건조 중 핵산 물질의 분해가 진행됨에 따라 신선도는 떨어지는 것으로 나타났고 핵산 물질의 변화에 의한 신선도 측면에서 인공건조가 자연건조보다 유리한 것으로 나타났다. (특히 IMP 등의 조합에 의한 맛의 상승작용으로 과메기 특유의 맛을 내는 것으로 사료된다.) 총 유리아미노산 함량은 2.98이었으며 glutamic acid, aspartic acid, histidine의 함량이 전체 유리아미노산의 함량이 34% 이상 차지하였다. 자연 및 인공건조동안 총 유리아미노산 함량은 서서히 증가하였으며 glutamic acid, histidine은 건조 3일째 이후부터 9일째까지 급속히 감소하였고 자연건조보다 인공건조의 감소가 더 크다. 자연 및 인공건조 중 lysine 함량은 점차 증가하였으며 threonine은 거의 변화가 없었다.

• 한국수산과학회지
• /
• 제53권4호
• /
• pp.524-529
• /
• 2020

Recently, several mutant laver Pyropia yezoensis strains were developed. In this study, control laver Pyropia yezoensis and its mutant Py500G were compared for their amino acid contents and antioxidative activities. There was no significant difference of total amino acid contents between wild-type and mutant Py500G, but mutant had higher free amino acid contents than wild-type. Also, total phenolic content was higher in mutant Py500G. Phycoerythrin and phycocyanin contents were higher in wild-type. But, antixoidative activities were shown to be higher in mutant Py500G. These results will be useful for the development of new cultivar of Pyropia.

• 한국산림과학회지
• /
• 제6권1호
• /
• pp.43-48
• /
• 1967

In the present experiment the amino acid composition in the pollen of Pinus taeda and Pinus rigida and methbolic changes of the composition occurring in germinating pollen were examined by the method of paper chromatography. The results obtained in this study are as follows. 1. The mature pollen of Pinus taeda and Pinus rigida contained 12.00%, 13.19% crude protein respectively and sixteen protein-constituting amino acids and three unknowns were detected on the chromatogram. 2. Main components of the protein-constituting amino acids were leucines, valine, alanine, glutamic acid and aspartic acid. 3. The free amino acids such as leucines, valine, tyrosine, alanine and glutamic acid increased evidently during germination of the pine pollen.

• Journal of Ginseng Research
• /
• 제44권3호
• /
• pp.424-434
• /
• 2020

Background: Amino acids are one of the major constituents in Panax ginseng, including neutral amino acid, acidic amino acid, and basic amino acid. However, whether these amino acids play a role in ginsenoside conversion during the steaming process has not yet been elucidated. Methods: In the present study, to elucidate the role of amino acids in ginsenoside transformation from fresh ginseng to red ginseng, an amino acids impregnation pretreatment was applied during the steaming process at 120℃. Acidic glutamic acid and basic arginine were used for the acid impregnation treatment during the root steaming. The ginsenosides contents, pH, browning intensity, and free amino acids contents in untreated and amino acid-treated P. ginseng samples were determined. Results: After 2 h of steaming, the concentration of less polar ginsenosides in glutamic acid-treated P. ginseng was significantly higher than that in untreated P. ginseng during the steaming process. However, the less polar ginsenosides in arginine-treated P. ginseng increased slightly. Meanwhile, free amino acids contents in fresh P. ginseng, glutamic acid-treated P. ginseng, and arginine-treated P. ginseng significantly decreased during steaming from 0 to 2h. The pH also decreased in P. ginseng samples at high temperatures. The pH decrease in red ginseng was closely related to the decrease in basic amino acids levels during the steaming process. Conclusion: Amino acids can remarkably affect the acidity of P. ginseng sample by altering the pH value. They were the main influential factors for the ginsenoside transformation. These results are useful in elucidating why and how steaming induces the structural change of ginsenoside inP. ginseng and also provides an effective and green approach to regulate the ginsenoside conversion using amino acids during the steaming process.

• 한국식품저장유통학회지
• /
• 제7권1호
• /
• pp.108-112
• /
• 2000

Proximate composition , volatile compounds, free amino acids, fatty acids and inorganic compounds in leaf, stem and root of Houttyunia cordata Thunb cultivated from two different area, Bosung and Sunchon , were analyzed. Each part of Houttuynia cordata Thunb from both local area showed moisture contents of 80-84% and crude ash contents of 2.1 ∼2.8%. Crude fat and protein contents were less than 3 % showing slightly higher contents in leaf than in both stem and root . Twenty six volatile compunds were identified from the parts of the plant, the volatile contents were high in the oder of leaf, root and stem. Major volatile compounds were mostly derivatives of decanoic acid ; decanoic acid, 20 tridecanoie, decanal and dodecanoic acid. Of free amino acids in leaf asparagine was the highest, while in stem hydroxyproline, proline and arginine were the major free amino acids. Linoleic acid was the highest in the stem and root, and linolenic acid was highest in leaf. the major minerals of all parts were K, Ca. Mg, P, Fe, Zn and Cu, showing highest with K.

• 한국식품저장유통학회지
• /
• 제10권1호
• /
• pp.65-69
• /
• 2003

본 연구는 능이버섯의 식품영양학적 및 기능성을 평가하기 위한 기초적인 연구로서 영양 성분의 함량을 조사하였다. 능이버섯의 일반성분은 수분 89.93%, 회분 1.18%, 조단백질 3.67%, 조지방 0.96%, 탄수화물 4.26%로 나타내었다. 능이버섯의 주요 유리당은 glucose, sucrose, trehalose, xylose 로 구성되어 있었고, trehalose의 함량이 가장 높았다. 능이버섯의 총아미노산의 함량은 796.85mg/100g-fr.wt.이었고, 필수 아미노산의 함량은 300.77mg/100g-fr.wt.으로 valine, leucine, threonine, Iysine의 함량이 비교적 높았고, 비필수아미노산은 486.08mg/100g-fr.wt.으로 alanine, glycine, aspartic acid, glutamic acid 등의 함량이 비교적 높았다. 총 유리 아미노산중에 필수아미노산과 비필수아미노산의 함량은 각각 124.95, 138.52mg/100g-fr.wt.이며, methionine, Iysine, valine, arginine, Aspartic acid, tyrosine 등의 함량이 높았다. 능이버섯에 존재하는 유리아미노산 유도체의 함량은 46.81 mg/100g-fr.wt.이었고, omithine, sarcosine, $\beta$-alanine, phosphoserine의 함량이 비교적 높았다. 능이버섯의 총 비타민 C 함량은 5.43 mg/100g이었고, 환원형과 산화형 비타민 C는 각각 3.50과1.93mg/100g이었고, 무기질 함량은 K, Na이 매우 높았고, 이들 함량은 각각 375.73, 61.82mg/100g이었다.

• 한국식품영양과학회지
• /
• 제32권6호
• /
• pp.785-789
• /
• 2003

산수유를 다양한 가공식품으로 개발하고 그 활용방안을 모색하기 위한 기초자료를 얻기 위하여 산수유의 부위별 일반성분, 유리당, 유기산, 유리 아미노산, 구성 아미노산, 무기질 및 지방산 성분함량을 분석하여 다음과 같은 결과를 얻었다. 산수유의 수분 함량은 과육, 씨 각각 74.52%, 30.13%, 조회분 함량은 과육, 씨 각각 1.53%, 1.82%, 조단백질 함량은 과육, 씨 각각 1.36%, 3.34%,조지방 함량은 과육, 씨 각각 1.24%, 6.12%, 조섬유 함량은 과육, 씨 각각 3.54%, 38.62%이었다. 그리고 환원당의 함량은 과육, 씨 각각 13.98%, 10.30%이었다. 산수유 과육과 씨에 함유된 유리당은 과육이 10,411.0 mg%이며, 씨는 8,258.4 mg%으로 과육이 씨보다 훨씬 많은 유리당 함량을 보였으며, 유기산은 malic acid 1,463.03 mg%로 가장 높았고, 씨의 경우에는 citric acid 158.12 mg%로 가장 높았다. 산수유의 과육과 씨에서 구성아미노산은 aspartic acid 외 17종이 검출되었고 구성아미노산 함량은 씨가 과육보다 3.83배 정도 높았으며 과육에서는 Gly가 32.24 mg%로 가장 높았고, 씨의 경우에는 Arg가 114.37 mg%로 가장 높았다. 산수유의 과육과 씨에 함유된 유리 아미노산 함량은 과육, 씨 모두 Arg가 가장 높았고, 각각 0.52 mg%, 0.60 mg%로 나타났다. 산수유의 과육과 씨에 함유된 무기질은 과육에는 K, Mg, Ca, Na, P, Fe, Zn, Cu, Mn 함량 순이었으며, 씨에서 Ca, K, Mg, Na, P, Fe, Zn, Mn, Cu 함량 순으로 검출되었다. 산수유의 과육과 씨에 함유된 주요 지방산으로는 linoleic acid가 과육에서 15.08 mg% 가장 많이 검출되었으며, 씨에서는 linolenic acid 65.44 mg%으로 가장 많이 검출되었다.