• Journal of the Korea Organic Resources Recycling Association
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• v.21 no.4
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• pp.62-71
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• 2013

This study was carried out to develope a pre-treatment technology for anaerobic digestion. Breaking down large particles into smaller particles enhances the performance of anaerobic digestion by increasing the hydrolysis of particles. A degree of hydrolysis is the most important factor determining the overall efficiency of methane production. Three types of pre-treatment devices (blade-type crusher, ozonization system, cavitation system) were set up and operated to crush solids in pig slurry in order to enhance biodegradability. The effect of pre-treatment on decreasing granular size within pig slurry by three experimental devices were compared. The highest performance of granulization of pig slurry was attained in a combination of blade-type crusher and ozonization system. In batch experiment, there was an improvement of the methane potential by combined pretreatment with crusher and cavitation. In case of pre-treated slurry, biogas and methane production were 325.9 L and 59.7% respectively, while, in untreated slurry, the production were lower; 298.8 L and 55.7%, respectively. These results indicate that higher anaerobic digestion efficiency of pig slurry can be obtained through the pre-treatment.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.29 no.5
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• pp.192-202
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• 2019

Physicochemical properties and sintering characteristics of pottery stone (Taebaek, Haenam, Aphae, Haengnam) were evaluated as a raw material for porcelain products. Due to acid leaching procedure, the concentration of iron oxide ($Fe_2O_3$) was decreased to < 1.0 wt%, which affects the whiteness of sintered samples. Mean particle size of acid leached samples is $5.7{\sim}10{\mu}m$ with narrow particle size distribution (PSD), which is lower than that of the pristine ($8{\sim}18{\mu}m$) with broad PSD. According to phase analysis by X-ray diffraction, most of pottery stones (PS) have Quartz phase as a main phase with Pyrophyllite as a second phase, however, Haenam PS shows halloysite phase. The absorption rate was in order of Taebaek (A, B, C)~Aphae (A, B) < Taebaek (Special A) < Haengnam < Haenam, and the samples sintered in reductive atmosphere showed lower absorption rate. This result might be due to the concentration of feldspar contained in PS, working as a flux in sintering process. Comparing the color of the sintered samples, the whiteness of refined PS (Taebaek special A, Haenam, Hangnam) is higher than acid leached PS (Taebaek A/B/C, Aphae A/B). The whiteness (L*) for refined PS is 95~97 %, which is higher than acid leached (82~96 %). This might be due to lower iron oxide concentration of the refined PS (0.11~0.58 %) than those of the acid leached PS (0.41~1.91 %) even though most of iron oxide was removed by acid leaching.

• Food Science and Preservation
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• v.15 no.6
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• pp.824-831
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• 2008

This study was conducted to determine the influence of heating and carbonic maceration (CM) pre-treatments prior to alcohol fermentation on wine quality from the main Korean grape variety, Campbell Early. Wine fermented with CM treatment had lower total acidity than control and heated wines. Wine fermented with heat treatment contained higher concentrations of anthocyanin and tannin than control wines, while CM-treated wine had the lowest concentrations. The red coloration of the wine was highly correlated with the polyphenol content, as a high content of anthocyanin and tannin resulted in increased red color intensity. The significant differences found in wine quality as a consequence of the use of pre-treatment techniques (heating and CM treatments) suggest their potential application in wine making.

• Applied Biological Chemistry
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• v.49 no.3
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• pp.202-208
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• 2006

Since abnormal fermentation and short storage duration of oriental melon are the main problems causing loss in commercial value, it is necessary to develop a food processing method using uncommercial melon. In this study, we suggested the effective pretreatment and storage conditions of melon as the material for alcoholic beverage production. Abnormally fermented melon had smaller carbohydrate and larger moisture content than normal one, indicating that carbohydrate in normal melon was probably converted to fermented products during fermentation. The sugar content of oriental melon was increased after fruiting and the highest value $(12.4^{\circ}Brix)$ was found at 5 weeks of storage. The maximum storage duration of normal and fermented oriental melons were 25 and 7 days at $4^{\circ}C$, and 8 and 4 days at room temperature, respectively. The oriental melon for fermentation-use could be conserved after slicing for 30 days at $4^{\circ}C$ with the addition of 1.5% citric acid and for one year at $-20^{\circ}C$ with the plastic film sealing, respectively.

• Food Science of Animal Resources
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• v.29 no.6
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• pp.695-701
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• 2009

This study was performed to evaluate the effectiveness of biological critical control points using the genetic profile of Escherichia coli isolates from pork cutting plants. Samples were collected from carcasses, equipment (knife, table, glove, transport belt, boning and skinning machine), the environment (wall and floor), and meat cuts during the cutting process from two plants. Pulsed-field gel electrophoresis (PFGE) was used to characterize the E. coli isolates. An identical genotype was detected from the carcasses, equipment, environment, and final meat cuts, and showed that the incoming carcasses, which were contaminated during transportation from slaughterhouses, were a major source of E. coli that was spread throughout processing. Also, consistent cross-contamination due to improper cleaning and disinfection procedures was another possibility. As a result, incoming carcasses and cleaning procedures should be considered critical control points in pork cutting plants, since a heating step is not used to inactivate microorganisms. Furthermore, the high rate (59.6%) of E. coli isolation indicates E. coli can be a good indicator in livestock processing plants even though it has genetic diversity.

• Food Science and Preservation
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• v.23 no.2
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• pp.204-210
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• 2016

This study aimed to find an effective preservation method of lotus leaves for the preparation of lotus-leaf Yakju throughout the year. The characteristics of Yakju containing lotus leaves pretreated by blanching, steaming, roasting, and drying were investigated in this study. The chemical properties of Yakju (pH, amino acidity, alcohol content, and volatile acid content) were significantly different for all treatments, except for the total acid content. The polyphenol content ranging from 315.89 to 462.63 ppm (p<0.05) was significantly different depending on pretreatment method L color value for Yakju was not significantly different all treatments, while a value was significantly different in Yakju containing frozen stored leaves after pretreatment. The b value was lowest for the blanching treatment, and was significantly different for all treatments. Among the organic acids present in Yakju, the oxalic, citric, and malic acid contents were significantly different for all treatments. In sensory evaluation, lotus-leaf Yakjus containing fresh leaves and dried leaves were preferred to the others in color and flavor among Yakjus prepared with lotus leaves before cold storage. However, among the Yakjus prepared with lotus leaves after cold storage, that containing blanched leaves was preferred to the others in terms of flavor, taste, and overall acceptability.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.1
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• pp.85-89
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• 2010

The uranium ingot casting process is one of the steps which consolidate uranium deposits produced by electrorefiner as an ingot form in a pryprocessing technique. This paper introduces new design concept of the ingot casting equipment and the performance test results of the lab-scale ingot casting equipment fabricated based on the design concept. Casting equipment produces the uranium ingot by pouring an uranium melt into a mold by tilting a melting crucible. Also it is equipped with a cup which is able to continuously feed uranium deposits into a melting crucible. The productivity could be significantly enhanced by introducing the continuous operation concept.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2002.05a
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• pp.27-36
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• 2002

1995년 이후부터 현재까지 전기로 제강더스트의 재활용 또는 처리에 대하여 국내 및 전 세계의 공개특허 및 연구논문을 분석하여 전기로 더스트의 재활용연구 동향을 파악하고자 하였다. 국내의 경우, 35건의 특허가 공개 또는 등록되었는데, 활용방법에 따라 분류하면 다음과 같다. 고형안정화처리가 6건, 케미칼 제조 7건, 아스콘 채움재가 4건, 토건재료로 활용이 3건, 습식처리 회수가 4건, 용융환원 3건, 폐수처리활용이 2건, 시멘트원료 1건, 건식회수법 5건으로 나눌 수 있다. 또한 년도별로는 95년 2건, 96년 1건, 97년 4건, 98년 4건, 99년 5건, 2000년 18건, 2001년 1건이 출원되었다. 2000년에 전체 출원 건수의 절반이 집중되었다. 미국특허는 이 기간중 39건이 등록된 것으로 검색되었다. 년도별로는 95년 3건, 96년 6건, 97년 5건, 98년 7건, 99년 9건, 00년 2건, 01년 3건, 2002년 4건(2개는 한국출원)이 검색되었다. 처리방법 별로는 마찰재 원료로 활용 3건, 고화처리 3건, 건식장치 1건, 습식처리 13건, 유동환원, 직접환원, 환원배소, 플라즈마환원등의 건식 처리법이 10건, 습식+건식콘크리트 4건, 폐수처리 활용 1건, 건자채 생산 1건등이 등록되었다. 국가전자도서관에서 EAF Dust를 키워드로 1993년 이후의 EAF Dust 관련 연구문헌을 검색한 결과 48건이 검색되었고, 01년에 5건, 00년에 3건, 99년에 4건, 98년 2건, 97년이 가장 활발하여 15건의 보고가 확인되었다. 96년에는 8건, 95년에는 3건의 보고가 검색되었다. 01년의 연구논문들은 direct recycling, reduction kinetics, distillation reduction등에 관심을 보이고 있었다. 가장 활발하게 많은 연구논문이 발표되었던 97년 이후에는 논문 발표수가 현저히 감소되어 97년 이후에 이 분야에 대한 관심이 감소하고 있음을 보여주고 있다.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.144-145
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• 2003

감자는 전세계 대부분의 국가에서 재배되고 있는 세계 4대 주곡 작물인 동시에 스낵류 시장에서도 중요한 부분을 차지하고 있다. 우리나라의 감자 가공산업은 1990년대 초부터 활기를 띠기 시작여하 현재 2,000억불의 매출을 달성하고 있다. 이중 우리나라 농민이 직접 생산한 감자를 원료로 사용하는 천연칩 감자 가공산업은 매출액을 기준으로 144억 (1997년)에서 700억 (2001년)으로 과거 10년 동안 괄목할 만한 성장을 하였다. 우리나라의 연간 감자 칩 원료용 가공용 감자 소요량은 총 51,600톤 (2002 년)으로 그중 40,600톤은 국내생산량으로 충당하고 나머지는 냉동감자를 수입하여 처리하고 있다. 가공원료용 감자는 괴경의 크기나 모양과 같은 외부품질과 환원당이나 고형분 함량과 같은 내부품질이 좋아야 한다. 하지만 가공용 감자의 내·외부품질이 좋게 판정되어도 내부갈색반점이나 중심공동과 같은 괴경 생리장해가 발생하면 원료용 감자로서의 상품 가치가 상실된다. 국내 칩 가공원료용 감자는 봄재배에서는 약 5 ∼ 7 ％, 여름재배에서는 10 ∼ 15 ％의 괴경 생리장해가 발생되고 있다. 현재 위와 같은 생리장해는 가공공장에서 감자를 잘라서 골라내거나 감자 칩을 만든 후 제거하는 방법을 쓰고 있다. 이에 감자를 수확 후 감자칩으로 가공하기 전에 생리장해가 발생한 감자를 제거하여 생산 공정에서의 불필요한 가공을 줄일 수 있는 방법이 개발되어야 할 필요성이 증대되고 있다. 최근, 농산물의 비파괴적 품질 평가와 선별에 있어서 가장 실용적이고 성공적인 기술 중의 하나는 농산물의 광학적 성질을 이용한 전기-광학 기술이다. 그중 X-선과 같이 파장이 짧은 방사 에너지는 대부분의 농산물을 투과하여 내부의 질량 밀도의 변화와 상관관계를 갖는 품질 인자를 비파괴적으로 평가하는데 적합하나 아직 국내에선 X-선을 이용한 가공용 감자의 내부 결함특성에 대한 연구는 이뤄지지 않고 있다. 이에 본 연구에서는 가공용 감자의 내부결함 특성중 하나인 내부동공의 X-선에 의한 특성을 본 연구소에 있는 X-선 발생장비로 측정해 보고 비파괴적인 방법으로 실시간 가능성을 시험하였다. 감자는 수원 농산물 도매시장에서 2003년산 가공용 감자 (품종:선농)를 구매하여 사용하였다. 감자내 내부동공은 35 ∼ 40 kV와 5.25 mA값으로 발생된 X-선에 의해 잘 검출되는 것으로 나타나, 현장에서 충분히 활용가능 할 것으로 판단되었다. 금후, 실시간으로 내부동공을 검출할 수 있는 시스템을 개발할 계획이다.

• Food Science and Preservation
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• v.17 no.5
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• pp.608-615
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• 2010

We investigated the effect of grape-must temperature ($50^{\circ}C$, $60^{\circ}C$, and $70^{\circ}C$) on wine quality. We used Muscat Bailey A (MBA) grapes; these are often used in wine making in Korea. The numbers of viable bacteria, yeasts and molds in grape-must decreased with an increase in temperature. Polyphenol oxidase activities in grape-must were reduced at high temperatures. Redness; and, total anthocyanin, polyphenol, and tannin contents of MBA grape wine were higher after heating at $70^{\circ}C$ than after use of lower temperatures. Antioxidant activity was also enhanced after exposure to high temperatures, which may be attributable to the presence of increased levels of polyphenolic compounds in the grape-must. Thus, the heat treatment to prepare grape-must before wine fermentation greatly affects wine quality.