• Title/Summary/Keyword: $CO_2$-cut

Search Result 347, Processing Time 0.029 seconds

Improvement of Shelf-life and Quality in Fresh-cut Tomato Slices

  • Hong, Ji-Heun
    • Food preservation and processing industry
    • /
    • v.3 no.1
    • /
    • pp.42-46
    • /
    • 2004
  • Quality of fresh-cut tomato slices was compared during cold storage under various modified atmosphere packaging conditions. Chilling injury of slices in containers sealed with Film A was higher than with Film B; these films had oxygen transmission rates of 87.4 and 60.0 ml h-1 m-2 nun-1 at $5^{\circ}C$ and $99\%$ RH, respectively. While slices in containers with an initial atmospheric composition of air, $4\%$ CO2 + 1 or $20\%\;O_2, \;8\%\;CO_2+1$ or $20\%\;O_2$, or $12\%\; CO_2+\;20\%\;O_2$ showed fungal growth, slices in containers with $12\%\;CO_2 +\;1\%\;O_2$ did not. Low ethylene in containers enhanced chilling injury. Modified atmosphere packaging provided good quality tomato slices with a shelf-life of 2 weeks or more at $5^{\circ}C$. Experiments were conducted to compare changes in quality of slices of red tomato (Lycopersicon esculentum Mill. 'Sunbeam') fruit from plants grown using black polyethylene or hairy vetch mulches under various foliar disease management systems including: no fungicide applications (NF), a disease forecasting model (Tom-Cast), and weekly fungicide applications (WF), during storage at $5^{\circ}C$ under a modified atmosphere. Slices were analyzed for firmness, soluble solids content (SCC), titratable acidity (TA), pH, electrolyte leakage, fungi, yeasts, and chilling injury. With both NF and Tom-Cast fungicide treatments, slices from tomato fruit grown with hairy vetch (Vicia villosa Roth) mulch were firmer than those from tomato fruit grown with black polyethylene mulch after 12 days storage. Ethylene Production of slices from fruit grown using hairy vetch mulch under Tom-Cast was about 1.5- and 5-fold higher than that of slices from WF and NF fungicide treatments after 12 days, respectively. The percentage of water-soaked areas (chilling injury) for slices from tomato fruit grown.

  • PDF

Quality changes of fresh-cut winter squash treated with different postharvest ripening periods and packaging methods (신선편이 단호박 원료의 후숙기간 및 가공 후 포장방법에 따른 저장 중 품질변화)

  • Kim, Ji-Gang;Choi, Ji-Woen;Cho, Mi-Ae
    • Food Science and Preservation
    • /
    • v.21 no.1
    • /
    • pp.17-24
    • /
    • 2014
  • This study was conducted in order to evaluate the effect of postharvest ripening periods and packaging methods on maintaining the quality of fresh-cut winter squash. Winter squash (var. Bouchang) was ripened at $22^{\circ}C$ for 1 or 2 weeks after harvest. The samples were washed in tap water, sanitized in $100{\mu}L/L$ chlorine water, peeled, and cut into 16 parts. Samples were then vacuum packaged or non-vacuum packaged in $80{\mu}m$ nylon/polyethylene (Ny/PE) films and stored at $5^{\circ}C$ for 21 days. Results indicated that different postharvest ripening periods affected gas concentration, firmness, off-odor development, color, and overall quality of fresh-cut winter squash. Samples treated with 2-week ripening periods maintained quality with higher redness value and soluble solid content (SSC) and lower $CO_2$ concentration and off-odor development compared to samples treated with a 1-week ripening period. Non vacuum packaging was effective in increasing visual quality and reducing off-odor development. A combination treatment of 2-week ripening periods and non-vacuum packaging maintained good quality with the lowest off-odor development and the highest visual quality scores at the end of the storage period.

Preparation and Properties of Hollow Fiber Membrane for CO2/H2 Separation (이산화탄소/수소 분리용 중공사형 기체분리막의 제조 및 특성)

  • Hyung Chul Koh;Mi-jin Jeon;Sang-Chul Jung;Yong-Woo Jeon
    • Membrane Journal
    • /
    • v.33 no.4
    • /
    • pp.222-232
    • /
    • 2023
  • In this study, a hollow fiber support membrane was prepared by a non-solvent induced phase separation (NIPS) method using a polysulfone (PSf). The prepared hollow fiber support membrane was coated with PDMS and Pebax to prepare a hollow fiber composite membrane. The prepared composite membrane was measured for permeance and selectivity for pure CO2, H2, O2 and N2. Gas separation performance of the module having the highest selectivity (CO2/H2) among the prepared composite membrane modules was measured according to the change in stage cut using simulated gas. The composition of the simulated gas used at this time was 70% CO2 and 30% H2. In the 1 stage experiment, it was possible to obtain values of about 60% of H2 concentration and 12% of H2 recovery. In order to overcome the low H2 concentration and recovery, 2 stage serial test was performed, and through this, it was possible to achieve 70% H2 concentration and 70% recovery. Through this, it was possible to derive a separation process configuration for CO2/H2 separation.

A Study on the Magnetic Anisotrpy and Magnetoresistive Characteristics of NiFe/Cu/Co Trilayers (NiFe/Cu/Co 삼층막의 자기이방성과 자기저항 특성에 관한 연구)

  • 김형준;이병일;주승기
    • Journal of the Korean Magnetics Society
    • /
    • v.6 no.5
    • /
    • pp.323-328
    • /
    • 1996
  • NiFe($60\;{\AA}$)/Cu($60\;{\AA}$)/Co($30\;{\AA}$) trilayers were formed on the $4^{\circ}$ tilt-cut Si(111) substrate by rf magnetron sputtering method. With a Cu($50\;{\AA}$) underlayer, NiFe($60\;{\AA}$)/Cu($60\;{\AA}$)/Co($30\;{\AA}$) trilayers developed in-plane magnebc anisotropy and in-plane perpendicular alignment of easy axes in two magnetic components of NiFe($60\;{\AA}$)/Cu($60\;{\AA}$)/Co($30\;{\AA}$) trilayers has been found. The easy axis of Co layer consisbng of NiFe($60\;{\AA}$)/Cu($60\;{\AA}$)/Co($30\;{\AA}$) trilayers turned out to be along $4^{\circ}$ tilt Si <112> direcbon and that of NiFe layer along Si <110> direction. [NiFe($60\;{\AA}$)/Cu($60\;{\AA}$)/Co($30\;{\AA}$)]/Cu($50\;{\AA}$)/Si(111, $4^{\circ}$ tiIt-cut) trilayers showed about 2.2 % MR ratio at room temperature and large plateau in MR curves, which are more improved MR characteristics than those in [NiFe($60\;{\AA}$)/Cu($60\;{\AA}$)/Co($30\;{\AA}$)]/Cu($50\;{\AA}$)/glass trilayers with no appreciable magnetic anisotropy.

  • PDF

Quality Changes of Fresh-Cut Potatoes during Storage Depending on the Packaging Treatments (신선한 감자절편의 포장방법에 따른 저장 중 품질변화)

  • Lim, Jeong-Ho;Choi, Jeong-Hee;Hong, Seok-In;Jeong, Moon-Cheol;Kim, Dong-Man
    • Korean Journal of Food Science and Technology
    • /
    • v.37 no.6
    • /
    • pp.933-938
    • /
    • 2005
  • To investigate pertinent packaging treatment of fresh-cut potatoes (Solanum tuberosum L.), potato cubes were subjected to passive, gas exchange, and vacuum packaging conditions. Low density polyethylene film (LDPE), polypropylene film (PP), anti-fogging film (AP), and perforated film (PF) were used as passive packaging treatments. Mixed gases of 5% $CO_2/5%\;O_2$ (MA1) and 10% $CO_2/5%\;O_2$ (MA2) were applied as gas exchange packaging. Packs filled with cubes were kept at $5^{\circ}C$, and changes in weight loss, surface color, vitamin C content and sensory quality of cubes were analyzed during storage. Respiration rate of cubes was 2.11 times higher than that of intact raw potatoes at $5^{\circ}C$. Gas concentrations in passive packaging was maintained at 1-2% $O_2$ and 4-14% $CO_2$ after 7 days. Gas levels changed depending on films used. Cubes packed in PP and MA2 showed lowest weight loss and browning during storage. Firmness of cubes was not affected by packaging treatment. Vitamin C content was highest in cubes packed with AF. Cubes packed in MA2 showed highest quality upto 10days storage, followed by those packed in PP and AF.

A study on calculating emission $CO_2$ and Analysis Logistics Cost in inland transportation (운송수단별 내륙운송의 $CO_2$ 배출량 산출 및 비용분석)

  • Kim, Hwan-Seong;Jo, Min-Ji
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
    • /
    • 2009.10a
    • /
    • pp.11-13
    • /
    • 2009
  • As the quantity of goods transported, port industry and inland transport industry have developing still, but almost 80% of inland transport industry consists of ground transport. According to issue "global warming", many regulations and agreements with countries in the world are becoming necessary and it is being fulfilled now. It is sure that Korea will have duty to reduce CO2 emission from 2013. And inland transport have to cut CO2 emission down. Therefore, this paper will address that calculate CO2 emission under route of transportation container at Korea by using O/D analysis. And then, it will predict routes of transportation containers which can reduce CO2 emission.

  • PDF

Numerical analysis to determine fire suppression time for multiple water mist nozzles in a large fire test compartment

  • Ha, Gaghyeon;Shin, Weon Gyu;Lee, Jaiho
    • Nuclear Engineering and Technology
    • /
    • v.53 no.4
    • /
    • pp.1157-1166
    • /
    • 2021
  • In this study, a numerical sensitivity analysis was performed to determine the fire suppression time for a large number of water mist nozzles in a large fire compartment. Fire simulations were performed using FDS (Fire dynamics simulator) 6.5.2 under the same condition as the test scenario 5 of the International Maritime Organization (IMO) 1165 test protocol. The sensitivities of input parameters including cell size, extinguishing coefficient (EC), droplets per second (DPS), and peak heat release rate (HRR) of fuel were investigated in terms of the normalized HRR and temperature distribution in the compartment. A new method of determining the fire suppression time using FDS simulation was developed, based on the concept of the cut-off time by cut-off value (COV) of the heat release rate per unit volume (HRRPUV) and the cooling time by the HRR cooling time criteria value (CTCV). In addition, a method was developed to determine the average EC value for the simulation input, using the cooling time and cut-off time.

Effects of Harvest Seasons on Quality and Microbial Population of Fresh-cut Iceberg Lettuce (수확시기가 신선편이 결구상추의 품질 및 미생물수에 미치는 영향)

  • In, Byung-Chun;Kim, Ji-Gang;Nimikeatkai, Hataitip;Lee, Jung-Soo
    • Journal of Bio-Environment Control
    • /
    • v.19 no.4
    • /
    • pp.343-350
    • /
    • 2010
  • This study was conducted to investigate the effect of harvest seasons on quality and microbial population at different steps of production chain of fresh-cut iceberg lettuce. Iceberg lettuces harvested in May, June, July, October, and December were processed following industrial practices, and stored at $5^{\circ}C$ for 9 days. For microbial measurement, samples were taken from each of the following steps: harvest, transport, pretreatment, cutting, 1st-washing, 2nd-washing, and day 3, 6, and 9 of storage. Iceberg lettuce cultivated in protect house and harvested in May and October showed higher $CO_2$ levels in the packages and electrolyte leakages than lettuce harvested in June, July and December. Microbial population of raw materials harvested in July was highest (6.76 log), and microbial growth rate during storage was highest in samples harvested in May. Lettuce harvested in June had better quality and microbial safety compared to other lettuces. Although lettuce harvested in October and December had less microbial population in either raw materials or processed products, those samples had inferior quality due to off-odor development and severe browning. Therefore, it is required to maintain quality and ensure microbial safety to distribute fresh-cut lettuce with high quality and safety throughout the year.

Effects of Shipping Temperature and Harvesting Stage on Quality and Vase Life of Cut Flowers in Dendranthema grandiflorum 'Baekma' for Export (수출용 국화 '백마'의 수송온도 및 수확시기에 따른 절화 품질과 수명)

  • Yoo, Yong Kweon;Roh, Yong Seung
    • Horticultural Science & Technology
    • /
    • v.33 no.1
    • /
    • pp.61-69
    • /
    • 2015
  • This study was carried out to investigate the effects of shipping temperature and harvesting stage on the quality and vase life of cut flower in standard chrysanthemum 'Baekma' for export. Cut flowers harvested at flowering stage 4 were stored for 24 hours at $5^{\circ}C$, and then quality and vase life were evaluated after simulated shipping for 48 hours at 5, 20, and $35^{\circ}C$. In addition, cut flowers harvested in flowering stage 1 to stage 6 were evaluated after simulated shipping for 72 hours at $5^{\circ}C$. As shipping temperature increased, $CO_2$ concentration inside the box rapidly increased, and $O_2$ concentration greatly decreased. The vase life of cut flowers was extended by 3 days and chlorophyll content of leaves, fresh weight, solution uptake, and flower diameter were better maintained in $5^{\circ}C$ shipping than in 20 or $35^{\circ}C$ shipping. The vase life of cut flowers harvested at flowering stage 1 or 2 was extended by 5.2 or 5.5 days compared to those harvested at flowering stage 6, more 6. The fresh weight was lower and flower diameter was smaller by 1.3 or 2.5 cm in cut flowers of flowering stages 1 through 3 than flowering stages 4 through 6. In addition, the cut flowers of flowering stages 4 through 6 showed higher solution uptake than those of flowering stages 1 through 3. These results suggest that shipping at $5^{\circ}C$ of cut flowers harvested at flowering stage 4 is preferential for promoting vase life and quality of cut flower in standard chrysanthemum 'Baekma' for export to Japan.

A Study on Heating Energy Monitoring of a Rural Detached House Applying Passive House Design Components (패시브 하우스 디자인 요소를 적용한 농촌지역 단독주거건물의 난방에너지 모니터링 연구)

  • Cho, Kyung-Min;Lee, Tae-Goo;Han, Young-Hae
    • KIEAE Journal
    • /
    • v.13 no.2
    • /
    • pp.39-46
    • /
    • 2013
  • Recently, the field of construction is putting a variety of effort into reducing CO2, since global warming is being accelerated due to climate changes and the increase of greenhouse gas. For reduction of CO2 in the field of construction, it is required to make plans to cut down heating energy of buildings and especially, it is urgently needed to cut down energy of residential buildings in rural area where occupies the majority of consumption of petroleum-based energy sources. Therefore, this research compared and analyzed the actual energy consumption, by evaluating energy performance of a detached house applying passive house design components for reduction of energy. As the result, energy consumption showed remarkable differences, according to the operation of a heat recovery ventilation unit which is one of passive house design components, and building energy consumption displayed remarkable differences, too, depending on the difference of airtightness performance during building energy simulation conducted in process of design. Based on these results, the importance of airtightness performance of passive house was verified. The result of the actual measurement of energy consumption demonstrated that LNG was most economical amongst several heat resources yielded, on the basis of LPG source energy consumption measured within a certain period of time, and it was followed by kerosene. LPG was analyzed to have a low economic efficiency, when used for heating.