• Food Science and Preservation
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• v.4 no.1
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• pp.27-32
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• 1997

Natural convection in agricultural-products storage system was analysed theoretically, The storage system was modelled by Internally heated fluid saturated porous layer. Darcy's law was used to explain characteristics of fluid motion. Stability equations were obtained under the linear stability theory and transfer characteristics were modelled by the shape assumption. Based on the modelling of transfer characteristics, heat trasnfer correlations were derived theoretically.

• Food Industry And Nutrition
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• v.8 no.3
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• pp.23-27
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• 2003

• Food Science and Preservation
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• v.9 no.1
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• pp.46-50
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• 2002

This study was carried out for dietary safety based on the level of pesticide residues in 17 kinds of the agricultural products (apple, cabbage, cabbage kor, carrot, cucumber, pepper, onion, potato, radish, spring onion, pumpkin, lettuce, garlic, drapwort, spinach, leek crown daisy) consumed in Kyunggi-do and Inchon-city that provided for the army. From January 1998 to December 2001, ten organochlorine pesticides in 1075 samples were analyzed by using GC-ECD. According to the results, one kind of pesticides was detected in 135(12.5%) samples, and two kinds were in 7 (5.18%). While dicofol and tetradifon was not fecund. Detection rate of pesticides were 9.02% for $\alpha$, $\beta$-endosulfan, 2.8% far chlorothalonil, 0.46% for γ-BHC, 0.40% for chlorobenzilate, 0.33% for folpet, 0.28% far DDT, 0.15% for captafol, and 0.11% for captan. Dectection ranges of pesticides were from 0.001 to 0.092 ppm for $\alpha$, $\beta$-endosulfan, from 0.003 to 0.023 ppm for chlorothalonil, from 0.003 to 0.006 ppm far γ -BHC, from 0.001 to 0.003 ppm for DDT, from 0.009 to 0.095 ppm for folpet, 0.05 ppm for captan, 0.01 ppm for captafol, and 0.008 ppm far chlorobenzilatel respectively. Consequentlyl all detected pesticide levels in samples were below maximum residue limits(MRLs) in Korea and Codex.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.20 no.1
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• pp.1-6
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• 2014

Properly designed plastic packages of fresh produce can preserve the quality by maintaining the optimal modified atmosphere (MA) at optimal low temperature conditions, but cannot do so at temperature abuse conditions in retail stage due to occurrence of injurious package atmosphere coming from imbalance between respiration and package gas permeation. Master packaging system consisting of a double-layered secondary package wrapping several individual (primary) packages has been proposed and applied recently to the commodities of sweet persimmon, king oyster mushroom, chestnut and strawberry. The master (secondary) pack is designed to be stored and distributed under chilled temperature, and then dismantled when moved to the retail display from the presale chilled storage. The master packaging system taking into consideration temperature dependence of produce respiration and package gas transfer was looked into with examination of its design variables to maintain the beneficial MA. Mathematical model was provided to help the design of master packaging system creating the desired MA. Its benefits of quality preservation and its limitations in practices of fresh produce marketing were discussed. Further research direction to extend the applicability of the produce master packaging system was presented.

• 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.

• Applied Chemistry for Engineering
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• v.23 no.6
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• pp.608-613
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• 2012

Dielectric barrier discharge plasma reactor was applied to the removal of ethylene from a simulated storage facility ($1.0m^3$) of fruits and vegetables. The system operated in a closed-loop mode by feeding the contaminated gas to the plasma reactor and recirculating the treated gas back to the storage facility. The experiments were carried out with parameters such as discharge power, circulation flow rate, initial ethylene concentration and treatment time. The rate of ethylene decomposition was mainly controlled by the discharge power and the treatment time. With the other conditions kept constant, the ethylene decomposition rate in the presence of the manganese oxide ozone control catalyst installed downstream from the plasma reactor was lower than that in the absence of it. The suggests that unreacted ozone from the plasma reactor accumulated in the storage facility where it additionally decomposed ethylene. On the basis of an initial ethylene concentration of 50 ppm, the energy requirement for completing the decomposition was about 60 kJ.

• Food Science and Preservation
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• v.14 no.1
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• pp.35-41
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• 2007

As the consumption of environmentally friendly agricultural products increases, food safety is at the forefront of public health concerns. We analyzed the biological hazards of 26 species of leaf vegetables and 4 species of fruit according to types of cultivation (conventional or organic filming) and distribution system (giant retailers or organic food stores) using various culture media, automatic bacterial identification systems, and microscopy, Total bacterial count of unwashed agricultural product ranged from $5.2{\times}10^{3}\;to\;1.5{\times}10^{5}\;CFU/mL$ (from 0.1 g of agricultural products), and the average count dropped 25-fold (range, 8-60-fold) after water washing. Microbial levels of washed organic agricultural products were $6.0{\times}10^{2}-1.9{\times}10^{4}\;CFU/mL$, and were not significantly different f개m the microbial loads on conventionally farmed produce. There was no significant difference in bacterial count from agricultural produce purchased from giant retailers or organic food stores. Total microbial count of Chinese cabbage, welsh onion, red chicory and kale were comparatively high, and Enterobacter cloacae was isolated most frequently. Parasites were detected in agricultural products purchased from conventional farm products in the stores of giant retailers, and in organic food stores, and parasite prevalence was especially high in Chinese cabbages and welsh onion. The study indicated that cultivation methods and distribution systems did not cause significant differences in biological contamination levels of agricultural produce. Some vegetables and fruits were highly contaminated effective sanitizing methods to reduce these biological hazards are needed.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.07a
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• pp.273-279
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• 2003

버섯은 수확 후 이산화탄소 발생량이 2$0^{\circ}C$에서 200-500mg$CO_2$/kgㆍhr로 호흡속도가 아주 높은 편으로 저장이나 유통 중에 호흡속도를 낮추는 것이 버섯의 품질유지에 효과적이다. 따라서 저장고 또는 포장내의 기체조성을 변화시켜 신선 농산물의 호흡속도를 조절하여 저장하는 CA(Controlled Atmosphere)저장법이나, MAP(Modified Atmosphere Packaging)저장법을 버섯 저장에 이용하는 연구들이 보고되고 있으며 환경기체조성이 저장중인 버섯의 생리적인 현상에 미치는 영향에 관한 연구도 보고되고 있다. (중략)

• Journal of Food Hygiene and Safety
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• v.28 no.4
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• pp.306-311
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• 2013

This study was conducted to investigate spoilage bacteria on organic and conventional fresh produce in Korea. Three samples (perilla leaf, cabbage, and romaine lettuce) of organic and conventional fresh produce were stored at $4^{\circ}C$ for 14 days and examined for spoilage bacteria on TSA. Isolated bacteria from organic and conventional fresh produces were identified using 16S rRNA sequencing method. Population of total aerobic bacteria on conventional perilla leaf, cabbage, and romaine lettuce were 7.59, 7.01, and $5.84{\log}_{10}CFU/g$, and populations of total aerobic bacteria were 6.72, 6.15, and $5.85{\log}_{10}CFU/g$, for organic perilla leaf, cabbage, and romaine lettuce, respectively. Major spoilage bacteria of organic and conventional fresh produces were similar however their levels were little different. For example, a major spoilage bacterium resulting the highest level on conventional perilla leaf was Stenotrophomonas maltophilia whereas that was Microbacterium sp. for organic produce. From these results, microflora or spoilage microorganism could be different depending on their cultivation types as conventional or organic produces and this information might be used for developing effective preservation method for different types of fresh produce.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2002.04a
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• pp.125-126
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• 2002