• 한국축산식품학회지
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• 제41권2호
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• pp.185-195
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• 2021

The objective of this study was to determine the effects of high pressure to investigate the technical functional properties of the protein solution extracted from an edible insect, Protaetia brevitarsis seulensis. High pressure processing was performed at 0 (control), 100, 200, 300, 400, and 500 MPa at 35℃. The essential amino acid index of the control was lower (p<0.05) than that of the P. brevitarsis seulensis extract treated with 100 MPa. The SDS-PAGE patterns tended to become faint at approximately 75 kDa and thicker at approximately 37 KDa after high pressure treatment. The protein solubility and pH of the protein tended to increase as the hydrostatic pressure levels increased. The instrument color values (redness and yellowness) of the P. brevitarsis seulensis protein treated with high pressure were lower (p<0.05) than those of the control. The forming capacity of the protein solution with P. brevitarsis seulensis treated with high pressure was higher (p<0.05) than that of the control. In conclusion, we confirmed that the technical functional properties of edible insect proteins extracted under high pressure of 200 MPa are improved. Our results indicate that high pressure can improve the technical functional properties of proteins from edible insects.

• Food Science and Biotechnology
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• 제15권4호
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• pp.523-528
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• 2006

The digestibility of heat- or high-pres sure-treated beef extracts was evaluated with an in vitro simulated gastric digestion model and each sample also underwent immune assay to detect its antigenicity with the sera of beef allergic patients. Heat treatment of the beef extracts considerably decreased their digestibility, whereas high-pressure treatment at 200 MPa improved their digestibility compared with the control, but the difference was not significant. The digestibility of the high pressure-treated beef extract was generally higher than that of the heat-treated samples. Depending on the degree of digestion, the degree of antigenicity of the main beef allergens decreased. On the basis of these results, we hypothesized that the allergenicity of beef could be eliminated if the allergenic proteins are sufficiently digested in the digestive organ, leading to the suggestion that the digestibility of allergenic proteins must be improved in food processing. In conclusion, high-pressure processing is a more acceptable food processing technique for beef considering its digestibility.

• 한국식품영양학회지
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• 제24권4호
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• pp.746-752
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• 2011

반고형 형태의 이유식 제조에 가장 적합한 물성을 부여하는 점증제를 선정하기 위해 쌀가루, 변성전분 1 및 변성전분 2를 4%를 첨가하거나 0.3% 펙틴을 첨가한 이유식을 550 MPa 압력에서 3분 동안 초고압 처리하여 점도를 측정하고 관능평가를 실시한 결과, 쌀가루를 첨가한 바나나와 사과 이유식 모두 색, 흐름성 및 질감에서 가장 선호도가 높았을 뿐 아니라 시판 이유식과 가장 유사한 점도를 보여 반고형 상태의 이유식 제조에 쌀가루가 점증제로 적합하였다. 점증제로 선정된 쌀가루를 4%, 6% 및 8% 첨가하여 제조한 이유식을 450 MPa과 550 MPa의 압력 조건에서 1, 3, 5분 처리한 결과, 쌀가루 첨가 비율이 높아질수록 점도와 색도의 밝기는 증가하였고, pH와 당도에서 유의적인 차이는 없었다. 또한 초고압 처리 조건에서 압력의 변화와 처리시간의 증가에 따른 유의적인 차이를 보이지 않는다. 즉 초고압 처리가 이유식의 물성에 영향을 크게 미치지 않으므로 경제성 및 점증제의 호화 정도를 고려하여 이유식 제조를 위한 초고압 처리 조건은 550 MPa, 3 min이 가장 적당한 처리 조건으로 판단되었다.

• 소성∙가공
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• 제16권5호통권95호
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• pp.360-363
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• 2007

Microstructure and microhardness of metallic powders of pure copper were studied after high pressure torsion(HPT) processing with 10 turns of die rotation and high pressure of 6 GPa. The grain size of copper decreases drastically after HPT and reaches nanometer size ranges. During HPT, the hardness of consolidates of copper powders increases with increasing the temperature of HPT processing. Examinations of the fracture surfaces indicated evidence of ductile fracture. The results proved that HPT of copper powders has a beneficial effect for homogeneous deformation with reducing grain size.

• Food Science and Biotechnology
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• 제15권1호
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• pp.13-18
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• 2006

Mandarin juice was processed using a continuous high pressure $CO_2$ system. Response surface methodology was used to investigate the effects of the processing parameters such as temperature, pressure, residence time, and %(w/w) ratio of $CO_2$ to juice on total aerobic count (TAC), pectinesterase (PE) activity, cloud level, $^{\circ}Brix$, pH, and titratable acidity (TA) of the juices. Maximum log reduction (3.47) of TAC was observed at $35^{\circ}C$, 41.1 MPa, 9 min residence time, and 7% $CO_2$. PE was inactivated by 7-51%. The cloud was not only retained but was also enhanced by 38%. Lightness and yellowness increased, and redness decreased. The processing temperature and % $CO_2$/juice ratio significantly affected high pressure $CO_2$ processing of the juice in terms of pasteurization, PE inactivation, cloud increase, and color change. The $^{\circ}Brix$, pH, and TA before and after treatment remained unchanged.

• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2003년도 추계학술대회 논문집
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• pp.111-114
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• 2003

Drop size is one of the most important parameters which are control the performance of the engine using liquid fuel/oxidizer and drop formation is mainly controlled by aerodynamic force caused by ambient gas. Because of this, empirical data and correlation acquired under standard ambient condition are not valid. So experiments under high ambient pressure condition to measure the drop size using image processing method And find the empirical correlation between SMD and chamber pressure(density), injection velocity.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.2122-2122
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• 2001

The ultra-high pressure technology fur the preservation of foods is under intense research to evaluate its potential as an alternative or complementary process to traditional methods of food preservation. Traditional processing methods usually need a large amount of energy, may cause unwanted reactions in the food, leading to cooked flavor and loss of vitamins, etc. The application of ultra-high hydrostatic pressure for food processing consists of subjecting the food to pressures in the range of 100-1000 ㎫. The ultra-high pressure inactivates the microorganisms and some enzymes, promotes the germination of spores and extends the shelf-life of the foods. This new technology follows the “minimal processing” concept minimizing the quality degradation, saving the vitamins, essential nutrients and flavors as well as utilizing less energy. We joined the research team at our University involved in the mentioned technology using an ultra-high pressure equipment, recording of the near infrared spectra and signal response of a chemosensor array (electronic nose) of their meat (beef and pork), vegetable and fruit samples exposed to different pressure. The results of our investigations achieved by evaluating the measured data using PCA and PQS methods will be presented.

• 한국식품저장유통학회지
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• 제24권3호
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• pp.343-350
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• 2017

초고압 공정(HPP)은 비가열 공정 중 하나로 식품 중의 세균 증식을 억제하는 방법으로 근래 들어 상업적으로 각광 받고 있다. 자작나무 수액은 여과 및 UV 살균과정을 거쳐 유통되지만 상업적으로 사용하기에는 식품공전 미생물 규격에 적합하지 않아 추가 살균처리 없이 유통을 하기에는 적합하지 않은 단점이 있었다. 본 연구에서는 그 단점을 보완하고 저장유통기한을 연장하기 위해 비가열가공 살균법으로 최근 주목받고 있는 HPP를 적용하고자 하였다. 최적 조건을 설정하기 위해 HPP 조건을 달리 하여 63일 동안 저장하여 변화를 관찰하였고, 그 결과 압력이 높고 처리시간이 길어질수록 미생물제어에 효과적이였다. 설정된 550 MPa, 120 sec의 조건으로 HPP 처리한 후 $5^{\circ}C$와 $10^{\circ}C$에 저장하며 미생물 및 품질변화를 관찰하였다. HPP 미처리군의 경우에는 4-7일차에 급격한 미생물 증식 및 이화학 변화가 일어났지만 HPP 처리군의 경우 $5^{\circ}C$에서 45일, $10^{\circ}C$에서 28일간 저장하는 동안 일반세균, 대장균, 대장균군, 진균 모두 증식이 없어 미생물학적으로 안전한 것으로 나타났다. 또한, pH, 산도, 당도, 탁도 및 갈변도의 변화를 살펴본 결과 $5^{\circ}C$에서는 45일까지 변화가 없었고, $10^{\circ}C$에서는 28일 차에서 pH 감소, 산도, 갈변도, 탁도의 증가로 급격한 변화로 24일 저장하는 것이 이화학적으로도 안정하다고 평가하였다. 이상의 결과로 볼 때 자작나무 수액은 효과적인 살균처리를 하지 않으면 미생물증식, 탁도 및 갈변도 변화, 산도증가로 유통기한이 4일 이하로 저장성이 많이 낮지만, HPP 처리함으로 인해 미생물 증식을 막고 그에 따른 수액의 이화학적 안정성을 확보하여 수액의 품질수명을 기존 미처리군에 비해 6배 연장시킬 수 있을 것으로 판단된다.

• 한국가시화정보학회지
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• 제3권1호
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• pp.63-70
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• 2005

Optical Line Patternator(OLP) has been applied to get a distribution of the spray at high ambient pressure. OLP is a combined technique of extinction measurement and image processing. The attenuated intensity of laser beam after traversing spray region was measured by using a photo-detector, and the line image of Mie-scattering was captured simultaneously in the path of each laser beam by using a CCD camera. The distribution of extinction coefficient in the spray is obtained by processing these data with the algebraic reconstruction technique. From the distribution of extinction coefficient, the surface distribution of spray can be reconstructed. OLP does not use laser sheet but use laser beam so that the noise effect of multiple scattering, caused by increasing number density of droplet in high pressure environment, is reduced drastically. OLP is expected as a suitable method which can investigate the characteristics of relatively large spray under the high pressure environment such as liquid rocket engine.

• KSBB Journal
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• 제23권5호
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• pp.362-368
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• 2008

본고에서는 초고압 시스템 (High hydrostatic pressure (HHP))의 특성, 종류, 응용을 예로 들어 설명하였다. 초고압 기술은 식품의 살균, 식품 보존기간연장, 유효성분의 추출 등에 선택적으로 적합하게 적용하여 생물산업공정에 효율적으로 응용 할 수 있다. 초고압 시스템을 효율적으로 적용하기 위한 최적조건을 선정하는 것은 많은 조업 변수에 대한 고려를 해야 하는 힘든 작업이다. 따라서 하드웨어에 대한 기초 실험과 예비 생산을 통하여 공정에 대한 모사를 검증하고 생산 효율을 증가시킬 수 있다. 또한 초고압 시스템의 중요성이 증가함에 따라 고성능 및 사용이 더욱 편리한 시스템이 나타날 것이며, 많은 영역의 바이오산업에서 필수적으로 이용될 것이다.