• Title/Summary/Keyword: weight decay

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Storage Quality of Minimally Processed Onions as Affected by Seal-Packaging Methods (포장방법에 따른 신선 편의가공 양파의 저장품질 변화)

  • Hong, Seok-In;Son, Seok-Min;Chung, Myong-Soo;Kim, Dong-Man
    • Korean Journal of Food Science and Technology
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    • v.35 no.6
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    • pp.1110-1116
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    • 2003
  • The effects of packaging methods on the storage quality of minimally processed (prepeeled) onions were investigated to determine the optimal packing design. Various packaging treatments used for modifying headspace atmospheres included two passive MAP using LDPE and PP films, two active MAP using a gas mixture of 20% $O_2/10%\;CO_2/balance\;N_2$ and an ethylene scavenging sachet, and moderate vacuum packaging (MVP). The quality attributes of onion samples were evaluated periodically in terms of flesh weight loss, color of cut surface, decay ratio, microbial counts, and sensory properties during storage at $10^{\circ}C$ for 28 days. Packaging methods did not significantly influence surface color, weight loss, and microbiological populations of mesophiles, psychrotrophs, and lactic acid bacteria. They did, however, affect sensory characteristics as well as decay occurrence. Results indicated that seal-packaging with a gas-permeable plastic film under a mild vacuum condition could retain better onion quality in terms of microbial decay and visual sensory aspects as compared with the other packages.

Comparison of the change in quality indices during distribution period by import season in three grape cultivars

  • Kim, Sung-Joo;Noh, Soo-In;Lim, Byung-Sun;Chun, Jong-Pil
    • Korean Journal of Agricultural Science
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    • v.46 no.1
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    • pp.45-56
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    • 2019
  • As a result of analyzing the quality of imported grapes during the 2018 season, the hardness of the grape berry was found to be 10 N or less in total. In the case of Chilean grapes, the soluble solids tended to be lower as imports and distribution periods were delayed. The berry weight was the largest at 14.4 - 14.8 g for the 'Red Globe', 7.1 - 7.4 g for the 'Thompson Seedless' and 6.0 - 7.0 g for the 'Crimson Seedless'. The 'Crimson Seedless' grapes imported from Chile, which had a high berry shatter rate, had a shorter pedicel length, pad width and brush length than that of the other 2 varieties. Regardless of the grape varieties, the weight loss during the distribution at room temperature ($25^{\circ}C$) increased rapidly as the import season was delayed. Additionally, it was found that the later the distribution seasons, a higher stem browning index was observed regardless of the variety. The 'Thompson Seedless' was revealed to be more susceptible to browning than that of the other varieties. The shrinkage of the stem and the pedicel browning progressed within a short time during shelf-life as the distribution time was delayed. The incidence of berry decay of the imported grapes tended to increase with the progression of the distribution period. In the fruits distributed on April, except for the 'Crimson Seedless', the grapes were rapidly corrupted in the second half of the distribution. The 'Red Globe' grapes completely lost marketability due to a berry decay of 26.1% and 69.9% at 9 and 12 days after shelf-life, respectively.

Freshness of Tomatoes Cultivated in Egypt by Packaging Functional MA film (기능성 MA 필름으로 포장한 이집트산 토마토의 신선도)

  • Park, Hyung-Woo;Kim, Sang-Hee;Cha, Hwan-Soo;Kim, Yoon-Ho;Lee, Seon-Ah;Rabie, Samir M.
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.12 no.1
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    • pp.41-44
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    • 2006
  • To investigate the effect of functional MA film packaging on tomatoes produced in Egypt packed 7 kg corrugated paperboard box during 7 days of storage at room temperature, the weight loss, titratable acidity, soluble solid content(SSC, $^oBrix$), vitamin C and the rate of decay were measured. The weight loss in 0.06 mm functional MA film was 1.5%, but was 3% in non-packed tomatoes after 7 days of storage. The titratable acidity and SSC in functional MA film was kept higher than that of non-packed tomatoes and vitamin C and the rate of decay in functional MA film was changed lower than the others.

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Development of Functional Additives and Packaging Paper for Prolonging Freshness of Cut Flowers (절화류의 선도 유지를 위한 기능성 첨가제 및 포장 원지 개발)

  • 김철환;조성환
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.34 no.2
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    • pp.32-41
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    • 2002
  • To prolong freshness and to reduce a decay rate of cut flowers during storage and distribution, a new packaging paper was developed with grapefruit seed extracts(GFSE) as a natural microorganism control agent. The GFSE was fractionated in order to identify antibiotic fractions by HPLC equipped with C18-reverse phase column chromatography. Among the active fractions, three ones were identified as 1-chloro-2-methyl-benzene (ο-toluene), N, N-dimethyl-benzenemethaneamine, and 1-〔2-(2-ethylethoxy)ethoxy〕-4-(1,1,3,3- tetra methyl)-benzene, while the other three remained unidentified. The GFSE-added paper displayed an effective inhibitory activity against putrefactive bacteria and fungi which were involved in the decay of flowers. Despite excellent antimicrobial acts of the GFSE-treated packaging paper, it was not possible to prevent the cut flowers from being dehydrated during storage, which led to the reduction of their fresh weight. However, additional treatment for giving water- repellency property to the GFSE-treated paper decreased a reduction rate of the fresh weight up to around 50% compared to the only GFSE-treated one.

The effect of water turnover time on decomposition of wild rice (Zizania latifolia) and nutrient dynamics in an artificial wetland system

  • Lee, Bo Eun;Kim, Jae Geun
    • Journal of Ecology and Environment
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    • v.37 no.1
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    • pp.13-19
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    • 2014
  • The effect of different turnover time of water on the decomposition of emergent macrophyte litter (Zizania latifolia Griseb.) was investigated using a microcosm experiment. Microcosm treatment represented different turnover time of water; 1, 2, 4 and 8 weeks. The litterbags from each treatment were retrieved every 2 weeks until the 8th week and the water simultaneously sampled with the litterbag. The dry weight and the content of major cations in the litter, and the content of available N, P, and major cations in the water were analyzed. Dry weight loss after 8 weeks indicated the lower decay rates under the condition of short turnover time of water. Major cations from the litter and the water showed that the leached amounts of K and Mg from the litter were highest in the 2nd week and dramatically decreased from the 4th week. The dynamics of available nitrogen and phosphorus in the water showed that as the water turnover time was getting longer, the amounts of available nitrogen and phosphorus remained higher. These results suggest that wetlands with longer turnover time of water could maintain the increased nitrogen and phosphorus and no outflow of the nutrients could cause eutrophication problem.

Effects on Storage Life of Satsuma Mandarin as Affected by Wax-coating. Paper Packaging and Film Packaging (왁스코팅, 종이포장 및 필름포장이 온주밀감의 저장성에 미치는 영향)

  • 고정삼;김지용
    • Food Science and Preservation
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    • v.5 no.2
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    • pp.138-143
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    • 1998
  • The stowage effects of Satsuma mandarin(Citrus unshiu Marc. var. miyagawa) were investigated by selecting various pretreatmnents; non-tested, wax-coating, paper packaging, 0.02mm cryovac film packaging. Weight loss of film packaging was the lowest among that of others, but decay radio was increased highly at late stages of storage. Soluble solids, moisture content of peel and total sugar were maintained almost constant, but acid content, vitamin C and firmness were reduced gradually during storage at room temperature. For 100 days storage, losses from weight and decay of ton-treated, paper packaging, wax-coating and film packaging were 15.9%, 18.5%, 17.4% and 12.9%, respectively. Acid content was decreased loom 1.28% to 0.81∼0.91% after 100 days storage. Ethylene evolution was increased in a degree after 65 days storage, and the amount was increased repidly afer 115 days. it seemed to be derived from decayed fruits and physiological activities. CO2 content of inner part of fruits was increased between 40∼100 days after storage. Optimum storage period of early variety of Satuma mandarin was regarded for 100days on the basis of appeareance and taste.

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Changes in Physiologcal Properties of Garlic (Allium sativum L.) by Storage and Marketing Condition after Storage (저장 및 저장후 유통조건에 따른 마늘(Allium sativum L.)의 생리적 특성 변화)

  • 최선태;장규섭
    • Food Science and Preservation
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    • v.5 no.2
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    • pp.105-110
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    • 1998
  • To find out suitable storage and marketing condition, northern type 'seosan' garlic was stored for 3 months at controlled atmosphere(CA), modified atmosphere(MA), low(0~1$^{\circ}C$) and room temperature(20$\pm$5$^{\circ}C$), and then marketed at low(2~3$^{\circ}C$) and room temperature (20$\pm$5$^{\circ}C$)after storage. The physiological properties of garlic were investigated among treatments. The garlic respiration increased after 2 months at room temperature storage, which seem to be dormancy break time. During storage of garlic by CA, MA condition, sprouting and weight loss were prevented effectively by suppress of respiration, and hardness was maintained higher then those of the others. Decay rate occurred 8.1% at room temperature storage, 2% at MA storage but didn't occurred at CA and low temperature storages. When marketed at room and low temperature after storage, increment of respiration and sprouting were delayed, and changes of weight and hardness were low in garlics stored at CA and MA. Decay rate occurred high in garlics stored at MA and room temperature.

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A study on the decay of friction force during CMP (화학 기계적 연마에서 마찰력 감소에 관한 연구)

  • 권대희;김형재;정해도
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.05a
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    • pp.972-975
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    • 2002
  • An understanding of tribological behavior in CMP(Chemical Mechanical Polishing) is one of the most important things to reveal the mechanism of material removal. In CMP, the contact type is thought to be semi-direct, elastohydrodynamic contact type from the Stribeck diagram, which is a combination of solid-solid direct contact and hydrodynamic lubrication with thin liquid film. This study is focused on the decay of friction force during CMP from two points of view, one of which is change of the real contact area and the other is the decrease of the elastic modulus of the pad caused by the increase of the temperature during CMP Experiments are implemented with elastic modulus measuring system and tool dynamometer. Results show that the decay of friction force during CMP results from the decrease of the real contact pressure working on an abrasive, which is induced by the decrease of elastic modulus of pad caused by the increase of temperature. And, the phenomenon is thought to be happen specially in the case that the weight concentration of abrasive in slurry is small enough.

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A Research Trend on Space Charge Analysis in Polymer Irradiated by Electron Beam (온도 상승시에 전자빔 조사된 폴리머내의 전하 분포의 축퇴 현상 연구 동향)

  • Ko, Sung-Min;Kim, Nam-Yong;Kim, Dae-Yeol;Choi, Yong-Sung;Moon, Jong-Dae;Lee, Kyung-Sup
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.1992-1993
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    • 2007
  • Decay processes of accumulated charge in e-beam irradiated polymers during elevating temperature are observed using pulsed electro-acoustic measurement system. Since the polymeric materials have many superior properties such as light-weight, good mechanical strength, high flexibility and low cost, they are inevitable materials for spacecrafts. In space environment, however, the polymers sometimes have serious damage by irradiation of high energy charged particles. When the polymers of the spacecraft are irradiated by high energy charged particles, some of injected charges accumulate and remain for long time in the bulk of the polymers. Since the bulk charges sometimes cause the degradation or breakdown of the materials, the investigation of the charging and the decay processes in polymeric materials under change of temperature is important to decide an adequate material for the spacecrafts. By measuring the charge behavior in e-beam irradiated polymer, such as polyimide or polystyrene, it is found that the various accumulation and decay patterns are observed in each material. The results seem to be useful and be helpful to progress in the reliability of the polymers for the spacecraft.

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Influence of Copper Azole Retention Level to Wood Decay (목재 내 Copper Azole 보유량이 목재부후에 미치는 영향)

  • Lee, Hyun-Mi;Son, Dong-Won;Lee, Han-Sol;Hwang, Won-Joung
    • Journal of the Korean Wood Science and Technology
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    • v.43 no.1
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    • pp.112-121
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    • 2015
  • In this study, Copper Azole (CuAz), a domestically available wood preservative for pressure treatment, was employed to perform an experimental research on its infiltration and decay properties in Japanese Red Pine. Test specimens were pressure-injected with CuAz-2 preservative to measure its preservative effectiveness, and then its impact on weight and mass losses. Furthermore, wood specimens were treated with CuAz-2 preservatives of various concentration levels before they were decayed with brown-rot-fungi in order to observe decay properties on light microscope (LM) and field emission scanning electron microscope (FE-SEM). As a result, untreated specimen by Fomitopsis palustris showed the mass loss of more than 40%, and the value of preservative effectiveness of CuAz-2 by indoor decay was $1,73-3.32kg/m^3$. The concentration levels of CuAz-2 preservative were shown to cause significant variations in terms of decay progresses in the cross section, radial section, and tangential section. By contrast, untreated specimens had underwent serious decays in early wood, late wood, longitudinal resin canals, and ray, which led to vertical destruction of wood texture. As for the radial section, ray tracheid, ray parenchyma cell, and window like pits were decayed and destroyed. In the case of tangential section, uniseriate rays and vertical resin canals were seriously decayed. In conclusion, this study indicates that the adequacy of the current CuAz injection amount should be reviewed in the domestic environment because there are significantly different decays at different decay conditions.