• Food Science and Preservation
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• v.13 no.4
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• pp.427-431
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• 2006

The research was conducted to measure the effect of pressure cooling of 'Fuji' apple during of 24 weeks. Weight loss in pressure cooling was lower than control at 24th week, and firmness in pressure cooling was higher than control. Titratable acidity in control and pressure cooling was 0.0823% 0.1103% in 24 weeks, respectively. Soluble solid content (SSC) in pressure cooling were higher than control. Decayed rate in control and pressure cooling was 46.4% 34.5% in 24 weeks, respectively. Total ascorbic acid contents were decreased in control and pressure cooling during 24 weeks. Therefore, it could be suggested that pressure cooling is more effective than control in storage of 'Fuji' apple.

• Horticultural Science & Technology
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• v.31 no.3
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• pp.308-316
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• 2013

Fresh ginseng has a limited storage life due to the quality change caused by microbial spoilage as well as physiological deterioration. The present study investigated the effects of 1-methylcyclopropene (1-MCP) treatment, an inhibitor of ethylene action, on the microbial growth and quality maintenance of fresh ginseng during storage. Harvested fresh ginsengs were treated with $1{\mu}L{\cdot}L^{-1}$ 1-MCP for 20 hours at $4^{\circ}C$ and then stored at room temperature (RT) for 18 days or low temperature ($4^{\circ}C$) for 160 days. After 18 days of storage at RT, the percentage weight loss in 1-MCP treated fresh ginseng (8.3%) is lower than that of control (10.1%). During long-term storage at $4^{\circ}C$, weight losses were increased slightly until 120 days without difference between non-treated and 1-MCP ginsengs. In contrast, after 120 days of storage at $4^{\circ}C$, higher increase in weight loss was observed in non-treated ginsengs than in 1-MCP treated ginsengs. Respiration rate and ethylene production of fresh ginseng were reduced by 1-MCP treatments at RT. The 1-MCP treatment also resulted in lower microbial population compared to those of non-treated ginsengs at RT. However, in ginsengs stored at $4^{\circ}C$ for short-term (45 days), no differences were noted in weight loss and microbial population between 1-MCP treated and non-treated ginsengs. Major ginsenosides was not changed by 1-MCP treatment during the 7 days of storage at RT. Results suggest that 1-MCP treatment can be used to maintain the freshness of ginseng at room temperature for short term storage and at low temperature for long term storage. 1-MCP treatment could be applied on fresh ginseng to avoid deleterious effect of exogenous ethylene during storage and shipping.

• Korean Journal of Agricultural Science
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• v.20 no.2
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• pp.167-180
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• 1993

Most of small size diesel engines are widely used with the same size and weight flywheel in the levels of 6.0kW and 7.5kW. This study was conducted to obtain basic data which affect the engine performance of the power tiller. The flywheel weight was considered as a major factor in this research. Basically, fuel consumption ratio, motoring loss, torque, vibration and mechanical efficiency of the engine were measured and analyzed on four levels of flywheel weight, 32.2, 29.4, 26.2 and $24.2kg_f$, respectively. Results were obtained as follows: 1. The weights of flywheel were $23.7kg_f$ from design program of JSME and $24.5kg_f$ from ASME and SAE design criteria. Therefore, the flywheel weight of $32.2kg_f$ might be reduced about $8kg_f$ in 7.5kW engine. 2. The rated outputs of 6.0kW and 7.5kW engine were actually 7.43kW and 7.85kW, respectively. When flywheel weight was reduced from $32.2kg_f$ to $24.2kg_f$, outputs were increased from 7.43kW to 7.70kW in 6.0kW engine and from 7.85kW to 8.25kW in 7.5kW engine. 3. When the flywheel weight was reduced from $32.2kg_f$ to $24.2kg_f$, fuel consumption ratio was decreased from 300.8 to 296.8g/kW-hr in 6.0kW engine and also from 313.6 to 312.8g/kW-hr in 7.5 kW engine, respectively. 4. When the flywheel weight was reduced from $32.2kg_f$ to $24.2kg_f$, mechanical efficiency of engine was increased from 76.1% to 76.8% in 6.0kW engine and also from 76.7% to 77.0% in 7.5kW engine, respectively. 5. When the flywheel weight was reduced from $32.2kg_f$ to $24.2kg_f$, vibration was decreased at X-axis and Z-axis in 6.0kW engine, however, slightly increased at Y-axis in 6.0kW engine and at all axes in 7.5kW engine. 6. When the flywheel weight was reduced from $32.2kg_f$ to $24.4kg_f$ motoring loss was decreased from 2.33kW to 1.75kW in 6.0kW engine and also from 2.46kW to 1.84kW in 7.5kW engine.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.131.1-131
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• 2003

충청북도 청원군 농가에서 재배한 검은비늘버섯((CBPM-6호)의 저장온도(1, 3, 6$^{\circ}C$) 및 포장 재료 (Wrap, PE, PP, AF)에 따른 선도유지 효과를 알아보기 위하여 중량감모율, 색도, 경도 및 신선도를 측정하였다. 그 결과, 저장온도와 포장재에 따른 선도유지효과에 대한 유의성 검정을 실시한 결과 고도의 유의차가 인정되었다(P<0.01). 중량감모율은 저장 18일 후 1$^{\circ}C$에서, AF필름은 1.08%, 랩포장에서는 3.17%를 나타내었고 6$^{\circ}C$에서는 AF 필름은 1.43%, 랩포장에서는 21.94%를 나타내었다. 포장재별 저장기간 중 색도는 저장기간이 연장될수록 명도와 황색도는 약간 증가하는 반면 랩 포장에서는 감소하는 경향을 나타내었다. 버섯 저장 전 색깔은 랩포장에서는 3일, PE, PP, AF포장에서는 18일까지 유지되는 것으로 나타났다. 경도는 저장온도가 높을수록 감소하는 경향을 나타내었으며 1$^{\circ}C$에서 AF 밀봉 저장시 경도의 변화가 가장 적은 것으로 나타났다. 저장중 신선도는 1$^{\circ}C$ 저장시 신선도 8을 기준으로 랩포장은 3일, PE 밀봉은 6일, PP 밀봉은 9일, AF 밀봉으로 15일간 상품성을 유지할 수 있었다.

• Journal of Korea Foresty Energy
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• v.20 no.2
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• pp.41-45
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• 2001

Japanese Larch(Larix kaempferi) was treated with aqueous solutions(30%, 40%, 50%) of polyethylene glycols(PEG, #1000, #1500, #4000, #6000) for the dimensional stabilization. The antiswelling efficiency(ASE) was measured for the evaluation of the dimensional stabilization. The weight percent gains(WPGs) of the woods treated with 40% solutions were higher than those of the others, and the highest WPG was achieved by treatment with 40% solution of PEG #1500. The ASE decreased with increasing molecular weight of PEG. ASE of woods treated with PEG #1000 and PEG #1500 were higher than those of the others.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.2
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• pp.152-157
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• 2014

The objective of this study is to examine the drying shinkage and autogenuous shrinkage strains of heavyweight magnetite concrete. As a main parameters, cement was partially replaced by fly ash (FA) from 5% to 35%. The measured shrinkage strains were compared with predictions obtained from CEB-FIP equations and Yang et al.'s model. Test results showed that the magnitite of the autogenous and total shrinkage strains of heavyweight concrete slightly increased as the amount of fly ash increases up to 15%, beyond which the strains tended to decrease. The CEB-FIP equations considerably underestimated the shrinkage behavior of heavyweight concrete, indicating that this trend was more notable with the age. On the other hand, Yang et al.'s model predicted accurately the shrinkage of heavyweight concrete.

• Food Science and Preservation
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• v.13 no.6
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• pp.675-680
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• 2006

Uniform milling is regarded as a very essential technology to produce high quality milled rice in Rice Recessing Complex. But non-uniformly milled rice can be produced very easily because of unadequate operation methods of milling system and bad brown rice conditions. This study was conducted to find out the bad effect of non-uniform milling degrees and store temperatures on quality characteristics such as taste of cooked rice, fatty acidity, whiteness and so on of milled rice during storage. According to the increase of non-uniform milling degrees, the fatty acid acidity and b value were increased very rapidly, and taste of cooked rice and whiteness were decreased very rapidly during storage. And the general quality characteristics of milled rice were better at low temperature storage of $5^{\circ}C$ than at high temperature storage at $25^{\circ}C$.

• Food Science and Preservation
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• v.20 no.5
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• pp.602-607
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• 2013

Correct packaging enables processors to pack fresh produce and extend its shelf life. This study was carried out to investigate the effect of different packaging materials on the weight loss, pH, $O_2$, $CO_2$ and sensory characteristics of soybean sprouts during their storage at $5^{\circ}C$ for seven days. Soybean sprouts ($320{\pm}20g$) were packaged with oriented polypropylene (OPP) and cast polypropylene (CPP) films, respectively. The $O_2$ transmission rate of the packaging materials was set to have a control of $10,000cc/m^2$.day.atm, and an OP15 and CP15 with $15,000cc/m^2$.day.atm through a pre-screening test. The average weight loss of the soybean sprouts during their storage was less than 10%, and that of the soybean sprouts with a CPP film was higher than that of the OPP film. The pH of the soybean sprouts increased during their storage regardless of their packaging materials; but compared to the pH of the soybean sprouts packaged with OPP, those packaged with CPP were higher. The $CO_2$ content of the packaging increased with a decrease in the $O_2$ content. The ratio of $CO_2$ to $O_2$ in the soybean sprouts with the OPP film was 3.5 times higher than in the soybean sprouts with the CPP film. The results of the overall sensory test showed that the marketability of the soybean sprouts packaged with OPP film and stored at $5^{\circ}C$ seemed to have been maintained effectively for six days (at a $15,000cc/m^2$.day.atm $O_2$ transmission rate). When the correlation coefficients of the control, OP15 and CP15 were analyzed, the highest correlation was shown between a control and OP15 (0.986; p<0.01).

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.132-132
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• 2003

포도 중 캠벨얼리 품종은 색이 검붉고 당도가 높아 우리나라 대표적인 품종 중에 하나로 알려져있다. 그러나 수확 후 저장 유통 중 품질이 저하되기 쉽다. 따라서 예냉 조건 및 수송, 저장, 유통조건에 따른 품질조사를 비교실험하여 가장 안전한 저장 유통 방법을 개발하고자 하였다. 실험재료는 2003년 8월20일경에 포도 주산지인 영천 농가에서 수화 한 후 바로 예냉처리를 하였다. 이때 사용한 예냉기는 원예연구소에서 개발한 시제작품을 사용하였다. 대조구로 무예냉을 두었으며 예냉 후 수송온도도 관행적인 상온과 저온(2$^{\circ}C$)로 구분 처리하였으며 저온온도별로도 함께 실험하였다. 포장단위도 2kg 와 5kg로 각각 처리하여 수행하였다. 예냉이 품질에 미치는 영향을 조사하기 위하여 예냉처리에 따른 호흡패턴 변화와 이화학적 특성변화를 조사하였다. 또한 저장 중 중량감소율, 부패율 및 탈립율을 조사하였다. 포도 ‘켐벨얼리’의 수확 시 품온 29.5$^{\circ}C$를 적정 저장 온도인 2$^{\circ}C$로 저하시키는데 일반 저온 저장고에서 10시간 정도 걸리는 데 반하여 차압예냉기 이용시 3시간으로 단축시킬 수 있었으며 예냉 포도의 처리구별 호흡량은 초기 6.65$m\ell$/kg/hr 였으나 상온무예냉 및 예냉 처리구의 경우에는 저장해가면서 급격히 증가되었고 저온에서는 무예냉의 경우에는 계속 증가되는 반면 예냉 처리구의 경우에는 포장 규격과는 상관없이 다른 처리구 보다 호흡억제 효과가 있었다. Ethylene 발생량 역시 호흡과 비슷한 경향을 보여 주어 예냉 시 과실의 품질 저하 요인 발생량을 억제시킬 수 있었다. 경도는 저장 기간이 경과됨에 감소되나 저온 예냉 처리구의 경우가 초기 1.26N을 높게 유지하였고 자연중량 감모율은 상온저장 2주째 무예냉처리구 8.40%로 감소된데 비하여 예냉 저온 수송 구의 경우에는 0.25%로 매우 낮았다. 포도 ‘켐벨얼리’의 저온 저장중 부패율은 저장 2주째 상온 무예냉 처리구의 경우 19.8%이었으나 저온 예냉 처리구의 경우는 부패과가 발생하지 않았고 탈립율 역시 상온무예냉처리구의 경우 53.5%인데 반하여 저온 예냉 처리구는 저장 4주경과 시까지 탈림과가 없었다. 당도 및 pH변화 역시 차압 예냉 후 저온 수송 처리구가 초기당도(12.0Bx)$^{\circ}$값과 초기 pH(3.8)를 저장 25일 경과시까지 유지하였다. 수확 시 높은 품온을 갖고 있는 과일을 산지에서 예냉 처리를 한 후 저온 냉장차를 이용하여 유통한다면 관행 유통 구조보다 고품질의 포도를 유통시킬 수 있는 것으로 사료되며 앞으로는 완숙된 고 당도(12.0~15.0Bx)$^{\circ}$ 포도를 수확 한 즉시 예냉 처리하고 저온 유통한다면 보다 신선한 과일을 소비자에게 전달 할 수 있을 것이다.

• Korean Journal of Food Science and Technology
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• v.27 no.3
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• pp.342-347
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• 1995

Experiments were conducted to investigate the effects of storage temperature and blanching treatment on the storage stability in order to extend the shelf life of Citrus junos. Chilling injury of Citrus junos was not observed at the temperature range of $0^{\circ}C{\sim}5^{\circ}C$. Respiration rate of Citrus junos classified into climacteric characteristics as storage time goes by increase of respiration rate. The $Q_{10}$ value of Citrus junos during storage appeared to have a narrow range of $2.3{\sim}2.4$ The decaying rate increased drastically at $20^{\circ}C$ ranging from 71.4% to 86.5%. It was not much influenced by the pretreatments but by the storage temperature. There was no difference in weight loss between the control and blanching treatment. The weight loss of Citrus junos at $20^{\circ}C$ appeared to be high during the 12 weeks period, and consequently the overall quality of Citrus junos was rapidly decreased. The ratio of brix to acid showed a slow increase for Citrus junos stored at $3^{\circ}C.\;At\;20^{\circ}C$, however, it increased rapidly and then decreased. This phenomenon was mainly due to the relatively high increase of brix, compared to the increase in acid content. Development of browning color in Citrus junos was mainly associated with Citrus junos peel, rather than with Citrus junos pulp.