• 한국토양비료학회지
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• 제49권3호
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• pp.265-270
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• 2016

Accumulated Phosphate can be released by ligand exchange reaction of organic acids. The objective of this study was to evaluate effects of the organic acids on the availability of phosphate and the growth of crop in phosphate and salts accumulated soil. Soil samples were collected from farmer's plastic film house. Available phosphate and electrical conductivity of soil were $3,005mg\;kg^{-1}$ and $16.63mg\;kg^{-1}$ which were 6 and 8 times higher than the optimum range of soil for crop growth, respectively. Corns were cultivated in pots for 2 months. Treatments were no treatment (control), phosphate fertilizer (P), citric acid (CA) 1, 5, 10 mM, and oxalic acid (OA) 1, 5, 10 mM. Water soluble phosphorus, available phosphate, corn growth and uptake were determined after cultivation. Results showed that organic acids increased water soluble phosphorus and available phosphate. For the level of 10 mM, the order of effectiveness of organic acids for water soluble P was citric acid (44%) > oxalic acid (32%). Height and dry weight of corns were increased significantly by the treatment of citric acid 1 and 5 mM. Also, corn absorbed more phosphorus, nitrogen, potassium, calcium and magnesium in the treatment of citric acid 1 mM than these of other treatments. Even though phosphate availability of soil was enhanced by addition of citric acid 10 mM, the growth of corns decreased because high concentration of citric acid caused salt damage by increasement of electrical conductivity. Thus, the citric acid of 1 mM has the potential to improve the availability of phosphate and the healthy growth of corns.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.310-313
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• 2003

The precipitation of heavy metals within the region of pH jump is inevitable in the conventional electrokinetic remediation technology. This study prevents the interest species from precipitating through the injection of flushing solutions in which HCl, acetic acid, citric acid, EDTA and SDS dissolved. The cumulative flow resulted from electroosmosis appear in order of Citric acid

• 한국식품영양과학회지
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• 제28권6호
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• pp.1269-1274
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• 1999

Four dimensional response surface methodology was applied to determine the optimum conditions on organoleptic properties to develop red pepper jam into Korean type jam. The organoleptic color of red pepper jam showed maximum score of 8.08 in 14.24g pectin, 256.2g sucrose and 8.31ml citric acid(50% citric acid solution). The organoleptic taste of red pepper jam showed maximum score of 6.77 in 14.23g pectin, 202.1g sucrose and 8.19ml citric acid. Optimum conditions on the organoleptic mouth feel of red pepper jam were 14.34g in pectin, 255.6g in sucrose and 8.39ml in 50% citric acid solution. Maximized overall palatability of red pepper jam was 7.25 in 14.15g pectin, 257.08g sucrose and 8.19ml of 50% citric acid solution. The optimum preparation condition ranges on organoleptic properties of red pepper jam were 14.0~15.5g pectin, 225.0~257.0g sucrose and 8.0~8.2ml of 50% citric acid solution.

• Preventive Nutrition and Food Science
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• 제9권2호
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• pp.121-125
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• 2004

Effects of chemical treatment with a citric acid solution or ozonated water on microbiological changes in lettuce and cabbage during storage were studied. Fresh lettuce and cabbage samples were cut into small pieces and treated by soaking in either ozonated water or a citric acid solution. After treatment, populations of total bacteria, yeast and mold, and E. coli were determined. Numbers of microorganisms increased during storage, but ozonated water and citric acid treatments retarded the increase in microbial growth. Among treatments, 1 % citric acid treatment was the most effective in terms of microbiological change and inhibition of polyphenoloxidase (PPO). For lettuce, citric acid treatment decreased the microbial growth overall by 1.5 log CFU/g and inhibited the PPO activity by 80%. These results indicate that chemical-treated lettuce and cabbage retained a better quality than those of the control during storage.

• 한국식품영양과학회지
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• 제29권5호
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• pp.790-795
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• 2000

To establish the optimum conditions for the extraction of anthocyanin pigment from purple-fleshed sweet potato, a suitable extraction solvent with the optimum citric acid concentration for acidification of the solvent, and the optimum extraction time and temperature were determined. Twenty percent ethanol solution acidified with citric acid was found to be a good solvent for the extraction of the pigment from purple-fleshed sweet potato. About 10 hour extraction at room temperature was appropriate for the extraction. pH of the extract was below 3 when more than 0.7% citric acid was added. The higher the concentration of citric acid added was, the higher the total optical density (TOD) of the extract was. However, the increase in TOD of the extract was insignificant when more than 1% of citric acid was added. Therefore, addition of 1% citric acid was determined for acidification of the extracting solvent. Though the initial rate of the pigment extraction increased as the extracting temperature increased, extraction at higher temperatures of 60 or 8$0^{\circ}C$ for an extended time caused a decrease in the extraction yield due to degradation of the pigment. The optimum extraction temperature for the anthocyanin pigment from purple-fleshed sweet potato with the solvent used was determined as 4$0^{\circ}C$.

• Applied Biological Chemistry
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• 제29권1호
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• pp.3-9
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• 1986

Alkane 효모의 유성(有性) 생활환(生活環)을 이용한 유전적 해석과 대사경로(代謝經路)에 관한 기초자료를 얻고자 토양과 오염된 치이즈에서 citric acid의 생산성이 높은 균주를 분리하여 동정하고 교잡(交雜)에 의하여 2배체(倍體) 체화(體化)하였으며, 이들의 유전적, 생화학적 및 효소학적 특성을 검토하여 다음과 같은 결과를 얻었다. Citric acid와 isocitric acid를 생산하는 CJ2, CJ7과 CJ8 균주는 Saccharomycopsis lipolytica의 교배형(交配型) A, B와 B로 각각 동정되어 교잡(交雜)과 포자형성(胞子形成)에 의하여 얻은 배수체(倍數體)의 감수분열(減數分裂) 분리를 행한바 재조합형(再組合型) 자손이 얻어졌다. 모든 균주는 glucose배지보다 n-hexadecane배지에서 재친(再親) 1배체(倍體)보다 2배체(倍體)가 citric acid를 많이 생산하였고 isocitrate Iyase의 비활성(比活性)은 n-hexadecane배지에서 생육한 세포가 glucose배지에서 생육한 세포보다 $15{\sim}20$배 높았지만 citrate synthetase의 비활성(比活性)은 탄소원에 의하여는 거의 영향을 받지 않았다. 또한 이들 효소의 비활성(比活性)과 citric acid의 생산 사이에는 균주와 배수성에 관계없이 상관관계가 적었다.

• 한국환경보건학회지
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• 제35권3호
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• pp.209-213
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• 2009

This study was carried out to investigate the distribution of V. parahaemolyticus in Incheon adjacent sea, and anti-microbial effect on growth of V. parahaemolyticus in organic acid. The detected strains were compared for geography, months and sample types. V. parahaemolyticus was detected form 28.5 percent of 287 samples collected from Incheon area, and 34.7 percent of 91 samples collected in the months of July through September, and 24.7 percent of 279 shellfish samples respectively. The minimun inhibitory concentration(MIC) of organic acid in V. parahaemolyticus were 1,250ppm at propionic acid, citric acid and acetic acid, 2,500ppm at vanillic acid, respectively. MICs of combined treatment of acetic acid and vanillic acid, citric acid and vanillic acid, propionic acid and vanillic acid were 1,250 ppm. MICs of combined treatment of citric acid and acetic acid, propionic acid and acetic acid, propionic acid and citric acid was 12.5ppm. The antimicrobial effect of organic acid in V. parahaemolyticus was confirmed from the result of this experiment.

• 한국식품영양과학회지
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• 제25권3호
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• pp.529-534
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• 1996

Using cystine, ascorbic acid and citric acid, retarding and synergistic effect on the browning reaction of onion juice concentrate was evaluated. Cysteine retarded the browning reaction most effectively followed by citric acid ; on the contrary, ascorbic acid accelerated rather than retarded the reaction at the concentration of 0.1%. The retarding effect of cysteine increased abruptly up to concentration of 0.3% and remained unchanged. Citric acid acted more effectively than ascorbic acid in terms of synergism. The browning reaction of onion juice concentrate exhibited activation energies of 62J/mol with cysteine and citric acid as compared to 73J/mol for control. $Q_{10}$ was determined to be 2.52 and 2.38 for control, 2.2 and 2.09 for treatment in the temperature range of 30~4$0^{\circ}C$ and 40~5$0^{\circ}C$, respectively.

• 한국식품과학회지
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• 제20권1호
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• pp.100-105
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• 1988

국내에서 인공재배되고 있는 느타리버섯 (Pleurotus ostreatus), 표고버섯 (Lentinus edodes), 양송이버섯 (Agaricus bisporus)의 유기산 및 지방산 조성을 GLC법에 의하여 분석하고 버섯의 종류, 크기, 부위에 따른 성분조성의 차이를 비교 검토하였다. 유기산은 3종의 버섯에서 lactic, oxalic, fumaric, succimic, malic, citric 및 pyroglutamic acid등이 확인되었고 malic, citric, pyroglutamic acid등이 많이 함유되어 있었다. 총 유기산 함량은 느타리버섯 $2.4{\sim}4.0%$, 표고버섯 $1.7{\sim}3.6%$, 양송이버섯 $1.9{\sim}3.1%$이었다. 부위별로는 갓부위가 자루부위보다 많았는데 느타리버섯에서는 oxalic과 pyroglutamic acid, 표고버섯은 malic과 citric acid, 양송이버섯은 fumaric acid가 특히 많았으며 크기별로는 크기가 클수록 총유기산 함량은 감소하는 경향이었고 특히 citric acid의 감소가 현저하였다. 지방산은 linoleic, palmitic 및 oleic acid가 주요 지방산이었으며 부위 및 크기별로 비교했을 때는 지방산 조성에 뚜렷한 차이가 없었다.

• 한국식품조리과학회지
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• 제19권6호
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• pp.777-782
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• 2003

본 연구는 안토시아닌 색소를 비롯한 여러 가지 생리활성 성분을 지니고 있는 오디 설기떡의 품질특성을 관찰하기 위해 수행되었다. 오디 설기떡의 최적 농도 조건 선정을 위해 수 차례 예비 실험한 결과 오디 4％ 첨가군이 가장 좋게 평가되었으나, 오디 특유의 새콤한 맛과 향 및 암회색의 색상을 나타내었다. 그러므로 오디 설기떡의 기호도를 높이고자 식품의 맛과 향 유지에 탁월한 효과를 내는 구연산 함량을 달리하여 특성을 관찰한 결과 구연산의 첨가량이 증가할수록 pH가 감소하였으며(p<0.01), 산도는 증가되었다(p<0.001). 수분함량은 실험군간에 유의적인 차이는 나타나지 않았다. 색도는 L값의 경우 대조군과 구연산 첨가군간의 유의적인 차이는 없었으나, 구연산 첨가량이 증가할수록 감소하는 경향이었다 적색도를 나타내는 a값 및 황색도를 나타내는 b값은 구연산 함량이 증가함에 따라 유의적으로 증가되었다(p<0.001). 견고성은 구연산 첨가군이 대조군보다 유의적으로 낮았으며(p<0.001), 응집성과 탄력성은 대조군과 0.1％ 구연산 첨가군간의 유의적인 차이가 없었다. 씹힘성과 깨짐성은 대조군이 각각 제일 크게 나타났다. 관능검사 실험결과 떡의 색상에 대한 기호도는 구연산의 첨가비율이 많아질수록 기호도 도 증가되었다. 맛, 씹힘성 및 전반적인 기호도에 대한 평가는 구연산 0.01％ 첨가구가 가장 높았다(p<0.001). 이와 같은 실험 결과로 안토시아닌을 비롯한 여러 가지 특수성분을 지니고 있는 오디 설기떡의 맛과 향 유지에 탁월한 효과를 내는 구연산을 첨가함으로써 떡의 대중화에 이바지 할 수 있으리라 사료된다.