• 생명과학회지
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• 제18권9호
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• pp.1271-1277
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• 2008

본 연구에서는 동결건조 방법과 저온 진공 건조기를 도입하여 양파를 건조한 후 유기 용매로 추출하여 인체 결장암 및 섬유육종세포에 대한 증식 억제 효과와 세포 내 활성산소종 억제 효과에 대해 비교 검토하였다. 저온 진공 건조방법으로 건조된 양파 분말의 A+M 추출물은 가장 낮은 농도인 0.5 mg/ml에서부터 농도 의존적으로 인체 섬유육종 및 결장암세포의 성장을 억제시켜 동결 건조된 양파 A+M 추출물보다 높은 증식 억제효과를 보였고(p<0.05), A+M 추출물과 비교했을 때 낮은 증식 억제효과를 나타내었으나 두 가지 건조방법에 따른 각각의 양파 MeOH 추출물도 암세포 증식 억제효과를 보였다(p<0.05). 동결건조 및 저온 진공 건조방법에 따른 양파 분획물들도 높은 암세포 증식 억제효과를 나타내었으며 그 중에서 동결 건조된 양파의 water 분획물과 hexane 분획물은 저온 진공 건조된 양파의 경우 보다 다소 높은 저해효과를 나타내었다(p<0.05). 따라서 A+M 추출물과 MeOH 추출물의 경우에는 저온 진공건조에 의해 건조된 양파 추출물에 의한 암세포 증식 억제 효과가 컸으며 분획물들의 경우에는 동결 건조된 양파 추출물의 억제 효과가 다소 높았다. 지질과산화물 생성 억제효과 실험에서는 두 가지 건조 방법에 의해 건조된 양파 분말의 A+M 및 MeOH 추출물들과 그 분획물들은 첨가농도 2.5 mg/ml에서 blank군과 control군과 비교하였을 때 측정 시간 120분 동안 계속적으로 높은 세포 내 지질 과산화물 생성 억제 능력을 나타내었다(p<0.05). 세포내 활성산소종 억제효과는 동결건조에 의해 건조된 양파보다 저온 진공 건조방법에 의해 건조된 양파 분말의 추출물과 분획물들에 의한 저해효과가 더 높았다.

• 동력기계공학회지
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• 제14권4호
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• pp.23-28
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• 2010

Of the roughly four million known substances, about 60,000 are processed and sold ; many of these must be dried. Many materials are processed in the liquid state - ideal for mixing and reacting - but most products are needed or wanted as dry, or relatively dry, solids. Usually operation is just below atmospheric pressure, as with direct dryers, but some are built for vacuum operation with pressures as low as 26.66kPa abs.. In spite of the global-class aquiculture agriculture and fisheries technology of our country, the processing technologies are lags behind the other nations relatively. These problems are considered to be caused directly by the lack of drying technologies. This paper is concerned to the experimental results of drying heat transfer characteristics for the green energy type vacuum dryer for the high quality agriculture and fisheries production.

• Journal of Advanced Marine Engineering and Technology
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• 제24권4호
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• pp.427-434
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• 2000

In tradition, there have been two kinds of drying methods, which are sun drying and artificial drying. The sun drying method which has been adopted traditionally has been replaced by the hot-air drying method which is one of the most general methods of artificial drying, with its simple drying system, low initial cost of drying plant, and easy operating method. But the hot-air drying method has some defects; (1) much energy loss happens due to the discharge of hot air during the drying process, (2) control of drying rate is not easy on account of changing relative humidity of inlet air for uniform hot air temperature, (3) high temperature of foods in drying process brings about the production of low-grade drying products. Vacuum drying takes advantage of energy saving and mass production because it reduces the drying time by increasing the drying rate under low temperature condition. The aim of this paper is to develop the low temperature vacum dryer, with low initial investments and operating costs, easy operating method and trouble-free operation.

• Journal of Advanced Marine Engineering and Technology
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• 제25권3호
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• pp.588-594
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• 2001

The aim of this paper is to develop the low temperature vacuum dryer, with low initial investments and operating costs, easy operating method and trouble-free operation Usally operations just below atmospheric pressure, as with direct dryers, but some are built for vacuum operation with pressure as low 50 mmHg abs. The lowers the boiling point to $39^{\circ}C$ The experimental data of quantitative analysis for using practically were obtained by the constant drying rate period and reducing drying rate period according to the temperature of hot water which is the experimental parameters of present experiment. As the results, it took about 20 hours for material to reach about 18% of the final moisture content is order to store products for a long time about 450% of the early moisture content at the beginning of drying and maximum drying rate comes to about 0.30 kg/m2hr at about 350% of the moisture content.

• International Journal of Industrial Entomology and Biomaterials
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• 제42권1호
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• pp.14-20
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• 2021

Mulberry was dried with low temperature vacuum dryer using microwave. The nutritional compositions of microwave-dried mulberry including proximate composition, sugar content, mineral content, total phenolic, flavonoids, and anthocyanin, beta-carotene, vitamin C, and amino acid composition were measured. Sugar contents of mulberry were 42.6 mg/100g (Cheongilppong) and 43.27 mg/100g dw (Gwasang No. 2). The main components of mulberry sugars were fructose and glucose. Mineral analysis showed that K, P, Ca, and Mg were abundant regardless of mulberry cultivars.

• 설비공학논문집
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• 제28권5호
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• pp.208-215
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• 2016

This study was conducted to improve the performance of low-temperature vacuum dryer by applying desiccant to cold trap. Performance evaluation was carried out using several desiccants. The amounts of absorption and diffusivity were measured based on analytic model. Results of desiccant performance evaluation revealed that silica-gel had the most excellent performance for conditions of low-temperature vacuum drying process. Silica-gel was applied to cold trap for evaluating the drying performance. The experiment results showed that the drying time was extended as the thickness of sample was increased due to increased heat and mass transfer resistance of drying sample. In addition, as heating plate temperature was increased, drying time was decreased due to increased evaporation pressure of drying sample. Furthermore, drying time with desiccant was decreased approximately 20% than that without desiccant.

• Journal of Advanced Marine Engineering and Technology
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• 제26권2호
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• pp.226-232
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• 2002

In tradition, there have been two kinds of drying methods, which are sun drying and artificial drying. The sun drying method which has been adopted traditionally has been replaced by the hot-air drying method which is one of the most general methods of artificial drying, with its simple drying system, low initial cost of drying plant, and easy operating method. But the hot-air drying method has some defects ; (1)much energy loss happens due to the discharge of hot air during the drying process, (2)control of drying rate is not easy on account of changing relative humidity of inlet air for uniform hot air temperature, (3)high temperature of floods in drying process brings about the production of low-grade drying products. Also, the hot-air drying method is inducing environmental and sanitary problems which are resulting from the emission of high temperature and high humidity air, including stick on the drying progress. Vacuum drying technique, whose drying time and 7uantity of exhausting energy is about 1/3 ~1/4 of hot air drying, is very excellent in the drying efficiency. As the results, it took about 20 hours for material to reach about 18% of the final moisture content in order to store products for a long time, from about 470% of the early moisture content at the beginning of drying, and maximum drying rate comes to about $0.35 kg/m^2hr$ at about 350% of the moisture content.

• 한국응용과학기술학회지
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• 제34권2호
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• pp.305-314
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• 2017

본 연구는 마이크로파 저온진공건조 기술을 이용하여 고효율 인삼개발을 하고자 하였다. 홍삼 제조 공정에서 증삼 후 $60-70^{\circ}C$에서 24시간 동안 건조하고 다시 $40^{\circ}C$에서 72시간동안 건조한 열풍 건조 홍삼과 증삼 후 마이크로파 저온진공건조기에서 900 watt, 2.45 MHz, 50 mmHg 조건으로 5시간동안 건조하고 다시 750 mmHg로 2시간동안 건조한 홍삼으로 조직 관찰, 관능평가, 진세노사이드 및 조사포닌 함량 변화 등을 비교하였다. 그 결과, 마이크로파 저온진공 홍삼은 색도가 밝은 색으로, 표면적은 다공성 조직으로 변화하였으며, 향미를 높이고 쓴 맛을 크게 감소시킴과 동시에 단 맛을 증가시켜 종합적인 선호도를 높였다. 또한, 단시간에 진세노사이드 $Rg_1$과 $Rb_1$ 함량을 열풍 건조 홍삼에 비해 1시간대에서 약 6배, 8배가 증가되었으나, $Rg_3$ 함량에서는 큰 차이가 나타나지 않았다. 마지막으로 조사포닌 함량은 10-20분대부터 크게 증가하여 이후 지속적으로 높은 함량이 나타났다. 이와 같은 결과를 종합해보면, 마이크로파 저온진공홍삼은 열풍 건조 홍삼에 비해 다공성 조직 변화를 통해 단시간에 진세노사이드 및 조사포닌에 대한 추출 수율을 높이고 향미와 식감을 개선시켜 홍삼에 대한 선호도를 높일 수 있음을 확인되었다.

• Journal of Advanced Marine Engineering and Technology
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• 제34권4호
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• pp.477-484
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• 2010

현재 국내 수산건조제품의 대부분은 천일(태양)건조에 의하는 실정으로 보관과 유통상의 위생안전성과 품질면에서 심각한 문제점을 안고 있다. 본 논문은 생산 현장에서 운용이 쉽고, 경제적이면서도 최고 건조품질을 유지할 수 있는 현장 지향적 저온진공 건조시스템의 설계 개발을 목표로 건조시간 경과에 따른 무게 감소율과 온도변동에 관한 실험적 결과를 요약하여 보고한 것이다.

• Journal of Ginseng Research
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• 제14권3호
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• pp.353-356
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• 1990

The isolation of volatile compounds by vacuum-distillation with freeze-drying was tested 1 with fresh ginseng roots. The roots were frozen at-8$0^{\circ}C$; they were dried at-4$0^{\circ}C$ tinder vacuum(40 tory), for 24 hours; and the ice condensed at the silrface of condenser in the freeze-dryer was thauved at room temperature. The ether extract of the resulting aqueous solution was analyzed by gas chromatography (GC) equipped with a flame ionization detector (FID) or a nitrogen-phosphorils detecto(NPD) and by gas : chromatography/mass spectrometry(GC/MS). More than forty peaks were observed in the CG(FID) profile. and more than ten peaks were observed in the GC(NPD) profile. Among them, thirteen components 1including one aldehyde, four hydrocarbons, two esters, folly alcohols, and two vyrazines were identified: six components the molesuiar ions of which were m/z, 204 were estimated to be a series of azulene compounds; and the other components unidentified were estimated to have molecular weights of lower than 254. Therefore, the freeze-drying technicue is thought to be usefu1 for the isolation of volatile compounds of such low molecufilar weights from vegetables, fruits and biological fluids as well as fresh ginseng roots under the tested conditions.