• Journal of the Korea Organic Resources Recycling Association
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• v.1 no.1
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• pp.103-113
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• 1993

Every year, over $3.37{\times}10^7$ ton of municipal solid waste is generated in Korea, of which about 28% is organic food waste from restaurant, dining halls and households etc. Methane conversion of the food waste by anaerobic digestion could be a viable approach for energy recovery as well as safe disposal of the waste. However, as food waste is composed of highmolecular complex polymers such as cellulose, lignin and protein, anaerobic digestion of food waste has not been efficient in terms of volumetric loading rate, solid retention time and extent of anaerobic degradation. In this research, the improved anaerobic degradation of food waste was attemped by applying rumen microorganisms to anaerobic digestion. Acidification efficiency of food waste by rumen microorganisms was compared with that of conventional acidogenesis. And optimum acidification conditions by rumen microorganisms were also determined. For the experiments, anaerobic batch reactors of 600 mL was fed with the processed (dried and milled) food waste obtained from a restaurant. Ultimate volatile fatty acid (VFA) yield produced by rumen microorganisms was about 8.4 meq VFA/g volatile solid (VS) that is 95% of the theoretical value. This yield was not much different from that of conventional acidogenesis, but hydrolysis rate was about twice faster. Cumulative VFA concentration increased from 66 meq/L to 480 meq/L, when the initial TS was increased from 1% to 15%. But VFA yield at 15% TS was half of that at 1% TS. This inhibition on the acidification might be caused by the rapid drop of pH and higher concentration of nonionized VFA. Optimal pH and temperature range for the acidification were about 6.0~7.5 and $35{\sim}45^{\circ}C$, respectively.

• Korean Journal of Food Science and Technology
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• v.27 no.2
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• pp.141-146
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• 1995

For the effective utilization of skipjack tuna viscera, a study was carried out to investigate the applicability of viscera protein hydrolysate (VPH) as a protein supplement in the processing of imitation sauce and bread. The optimum extraction and hydrolyzation conditions for the production of viscera protein concentrate (VPC) and viscera protein hydrolysate (VPH) were determined. Boiled viscera could be extracted by ethyl alcohol without significant deterioration as a raw material for the further processing. High quality of VPH could be obtained by hydrolysis with 1% pepsin under its optimum condition $(pH\;1.65,\;37^{\circ}C)$. The solubilities of VPC and VPH were 40% and 90%, respectively, and the essential amino acid contents in two products were 48.7% and 63.2%, respectively. Especially, the content of taurine, a physiologically important amino acid, was 9.4% in VPH. In experimental preparations of imitation sauce and bread, panel test showed that the supplementation of 10% of VPH in imitation sauce and $3{\sim}5%$ of VPH in bread was well accepted in sensory characteristics such as color, flavor, taste and texture.

• Korean Journal of Food Science and Technology
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• v.45 no.1
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• pp.34-39
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• 2013

This study was performed to investigate the antioxidant activity of mung beans with heat treatment at $130^{\circ}C$ for 2 h after acid hydrolysis. The browning index of heating after hydrolysis was 2.31 whereas heating before hydrolysis was 0.17. 5-hydromethyl-2-furaldehyde (5'-HMF) content was the highest value of 81.61 mg/g in heating after hydrolysis. The highest total polyphenol content (55.95 mg/g) occurred in heating after hydrolysis and this value was 6.4-fold higher than that of heating before hydrolysis (8.79 mg/g). 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity was the highest value of 22.19 mg AA eq/g sample in heating after hydrolysis whereas heating before hydrolysis was 1.75 mg AA eq/g sample.1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity was the highest value of 3.64 mg Trolox eq/g sample in heating after hydrolysis whereas heating before hydrolysis was not shown. These results suggest that heat treatment of mung beans for increasing the antioxidant activity could be effective after hydrolysis.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.286-290
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• 2010

Angiotensin-converting enzyme (ACE) inhibitory activity and production optimization of ovotransferrin hydrolysates were studied. Ovotransferrin was hydrolyzed by several enzymes (protamex, alcalase, trypsin, pepsin, neutrase, and flavorzyme) and acid (0.03 N HCl). Ovotransferrin hydrolysate reduced ACE activity by 60.2%, 55.8%, and 42.6% when treated with trypsin, acid, and pepsin, respectively. Trypsin was selected for production of peptide having maximum AC inhibitory effect, which was greatest with 7 h hydrolysis. Central composite design determined that optimum composition of ACE inhibitory substances using substrate concentration of 20-35%, temperature of $35-55^{\circ}C$, and pH of 6.0-8.0. The optimum composition was 1% trypsin, substrate concentration of 26.32%, $51.29^{\circ}C$, and pH 6.32. Under this conditions, a maximum ACE inhibitory effect of 69.1% was evident, similar to the predicted value.

• Clean Technology
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• v.15 no.4
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• pp.273-279
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• 2009

$SF_6$, which has a high global warming potential, can be decomposed to sulfur and fluorine compounds through hydrolysis by $H_2O$ or oxidation by $O_2$ over solid acid catalysts. In this study ${\gamma}-Al_2O_3$ was employed as the solid acid catalyst for the abatement of $SF_6$ and its catalytic activity was investigated with respect to the reaction temperature and the space velocity. The catalytic activity for $SF_6$ decomposition by the hydrolysis reached the maximum at and above 973 K with the space velocity of $20,000\;ml/g_{-cat}{\cdot}h$, exhibiting a conversion very close to 100%. When the space velocity was lower than $45,000\;ml/g_{-cat}{\cdot}h$, the conversion was maintained at the maximum value. On the other hand, the conversion of $SF_6$ by the oxidation was about 20% under the same conditions. The SEM and XRD analyses revealed that the ${\gamma}-Al_2O_3$ was transformed to ${\alpha}-Al_2O_3$ during the hydrolysis and to $AlF_3$ during the oxidation, respectively. The size of $AlF_3$ after the oxidation was over $20\;{\mu}m$, and its catalytic activity was low due to the low surface area. Therefore, it was concluded that the hydrolysis over ${\gamma}-Al_2O_3$ was much more favorable than the oxidation for the catalytic decomposition of $SF_6$.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1974.06a
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• pp.124.1-124
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• 1974

연모생산의 영소원으로서 농산폐자원인 고구마 전분박의 이용가능성을 검토한 결과 아래와 같다. 1. 고구마전분박의 산당화조건을 검토하여 본 결과 가수분해제로는 염산이 황기보다 효과적이였으며 소이남도 1%, 여도 $2.0kg/\textrm{cm}^2에서$ 30분간 가수분해시켰을때 당망율이 62.7%로서 가장 높았다.(중략)

• KSBB Journal
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• v.4 no.2
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• pp.99-103
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• 1989

The kinetics of secondary hydrolysis of hemicellulose prehydrolyzate by a solid superacid, Nafion, was investigated. The maximum attainable xylose yields determined from continuous column reactor operation were about 90%. Nafion was found to be a stable hydrolytic catalyst provided that the feed solution was free of cationic substances.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.05a
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• pp.272-275
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• 2005

본 실험은 염소계유해유기화합물을 처리하는 목적으로 종래의 초임계수산화법의 결점을 완전히 해결하기 위해서 도달한 것이 질산나트륨을 산화제로서 사용하는 개량된 초임계수 산화법(다단계산화법)이다. 이와 같이 본 연구팀이 개발한 개량된산화법(다단계산화법)은 매우 간단하며 저렴한 염소계유기물 분해처리시스템을 구축하는 것이 가능하다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.97-98
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• 2003

단백질은 각종 효소에 의하여 가수분해되면 여러 가지 생리활성을 나타내는 peptide를 생성하는 것으로 알려져 있으며 특히 젓갈류는 어육단백질이 가수분해되어 peptide나 아미노산을 생성하는 대표적인 식품이다. 본 연구에서는 전년도에 3,000 dalton 이상의 peptide에서 ACE 저해 작용을 조사한바 밴뎅 이, 조개, 까나리 및 멸치젓갈이 peptide-N 농도 0.2mg/mL에서 각각 94.4, 77.6, 73.8 및 69.2%의 저해능을 나타내었으나 비교적 큰 효과를 보지 못하였다. (중략)

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05b
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• pp.49-52
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• 2004

생체 내에서의 요소 형성은 단백질이 아미노산으로 분해되어 인체에 남은 요소는 오줌으로 배출된다. 그러나 고농도의 urea의 경우 단백질을 변형시키게 된다[1-2]. 이러한 고 농도의 urea를 단백질 공정을 통해서 제거시키는 기술이 최근의 투석 과학이다. 그러나 이러한 방법은 urea의 제거와 함께 많은 양의 단백질과 양이온이 유출 및 오염의 문제가 많이 발생하고 있다[3].(중략)