• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1137-1142
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• 1998

Modified atmosphere packagings were designed by combining the respiration characteristics of the enoki mushroom at 10oC and the measured film permeabilities to O2 and CO2 gases to attain the beneficial package atmosphere were fabricated and tested during storage. The packages of 100g size with 30 m low density polyethylene and cast polypropylene showed the good agreement between estimated and experimental package atmospheres. However, polyvinylchloride stretch wrap packs showed the gas composition close to the air, which was due to leaking of stretch wrapping. The CPP package attaining O2 below 1% and CO2 concentration of 15~20% gave the best retention of quality and thus the longest shelf life among the tried packages, and it was superior to the others in the Hunter L value, stipe elongation and sensory qualties.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.15 no.3
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• pp.93-98
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• 2009

Migration levels of plasticizers, di-n-butyl phthalate (DBP), benzyl-butyl phthalate (BBP), di-n-octyl phthalate(DNOP), di-iso-decyl phthalate (DIDP) and di-iso-nonyl phthalate (DINP), di-(2-ethylhexyl) adipate (DEHA), from 46 poly(vinyl chloride) (PVC) wrap films and 54 PVC gaskets into food simulants were determined using gas chromatography/mass spectrometry (GC/MS). The method was validated with limit of detection (LOD) of $0.01{\sim}0.02\;{\mu}g/mL$ for DBP, BBP, DNOP and DEHA, and $2\;{\mu}g/mL$ for DIDP and DINP. The linearity were found to be > 0.99 for all the compounds in concentration range of $0.1{\sim}81.4\;{\mu}g/mL$, and overall recoveries were ranged from 90.4 ~ 99.6%. DBP, BBP, DNOP, DEHA, DIDP and DINP were not detected in food simulants, except 1 wrap sample from which 0.28 and $0.99\;{\mu}g/mL$ of DEHA were detected respectively when tested with 20% ethanol and n-heptane as food simulants. These values were below the regulatory limitation in European Union (EU).

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1140-1145
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• 1998

Low density polyethylene (LDPE) films incorporated with 1% antimicrobial agents of Rheum palmatum extract, Coptis chinensis extract, and Ag-substituted inorganic zirconium matrix, were applied to modified atmosphere packaging of 200 g fresh strawberries. Plain LDPE film package, PVC wrap and perforative pinhole package of the film impregnated with 1% Rheum palmatum extract were also constructed for comparative purpose. All the packages were stored for 13 days at $5^{\circ}C$ and measured in package atmosphere, microbial count and quality attributes of the strawberry fruits. The antimicrobial LDPE films retarded the growth in total aerobic bacteria, lactic acid bacteria and yeast on the fruits, and resulted in significantly lower decay. The degrees of reduced microbial growth and fruit decay in the antimicrobial film packages were more pronounced, when applied by hermetical sealing to produce the modified atmospheres of low $O_2$ (<4.0%) and $CO_2$ concentrations with $6.3{\sim}9.0%$. The hermetically sealed packages of antimicrobial LDPE films also showed better retention of fruit firmness and did not give any negative effect on the physical and chemical qualities of strawberries.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.3
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• pp.418-429
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• 2012

In this study we surveyed the packaging preferences of consumers for Korean rice cakes as current commercial products in Korea. The questionnaire was developed from a preliminary investigation of typical rice cake packaging patterns and sent to 2332 residents in Korea by random sampling mail. The questionnaire contained questions on the preferences of interior design in packaging, opening methods, individually separated types, printing position, packaging methods, and packaging materials such as paper and plastic. There were responses from 304 residents. The collected data was analyzed by an SPSS package program. Most of the packaging used for Korean rice cakes was plastic (58.9%) which was used for packaging materials and stretch wrap (42.9%) as packing methods. The results showed the preference was the perforated line type used by hand for opening a packaging and interior packaging design with 2~3 partitions. Most respondents expressed an interest in using individual packaging and having printing directly on the packaging. Also, the respondents preferred the packaging design that let them see the contents of a package. Based on the results of the questionnaire, this paper suggested that most consumers would prefer to choose a packaging system with a partition design in a plastic container, individually separated products, and a transparent container for Korean rice cakes. The results of packaging preferences could provide important information for suitable packaging development for Korean rice cakes. Further research should be conducted to improve the shelf life of Korean rice cakes with functional packaging systems such as modified atmosphere packaging or anti-microbial packaging.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.969-976
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• 2002

The migrating level of di-(2-ethylhexyl) adipate (DEHA) in PVC wrap to various foodstuffs dishes was determined using acetone/n-hexane as an extracting solvent. The recovery ratio of DEHA from various foodstuffs ranged from 81.3 to 91.2%. During storage at $10\;or\;20^{\circ}C$ for up to 3 days, highest migration of 22.9 mg/kg occurred with pork belly, an indication that increases in fat content, storage temperature, and storage time result in increasing DEHA migration. DEHA concentrations of various delivered dishes ranged between 6.9 and 29.8 mg/kg, and highest migration was observed in Chambbong, which had the highest fat content among samples. After microwave-reheating, which resulted in a tight contact between film and food samples, DEHA was not detected in rice and potato, whereas up to 158.8 mg/kg was detected in pizza. When the wrap film was not contacted with the surface of food, the migration was lowered. Migration levels of DEHA from PVC wrap film into samples under various exposure conditions often exceeded the limit value of $3\;mg/dm^2\;and/or\;18\;mg/kg$ set by the European Union.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.715-720
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• 2007

The levels of butyltin compounds in poly(vinyl chloride) (PVC) food packaging using gas chromatography/mass spectrometry (GC/MS) were monitored. The analytical method, involving the ethylation with sodium tetraethylborate, was found to be selective and sensitive for mono-n-butyltin (MBT), di-n-butyltin (DBT), and tri-n-butyltin (TBT), validated by a $0.005\;{\mu}g/mL$ limit of detection (LOD), an $R^2>0.999$ for linearity, and >90% of recovery, respectively. Finally, none of the commercial food wraps and gaskets showed detectable levels of butyltin compounds.

• Food Science and Preservation
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• v.15 no.5
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• pp.622-629
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• 2008

This study investigated changes in quality characteristics of wrap- and vacuum-packaged peeled lotus roots treated with strong acidic electrolyzed acid water (SAEW pH 2.58, ORP 1,128 mV, HClO 105.0 ppm) or low alkaline electrolyzed water (LAEW pH 8.56, ORP 660 mV, HClO 73.8 ppm) as immersion liquids prior to packaging and storage at 5C. Immersion of peeled lotus roots in SAEW and LAEW reduced initial microbial load by about 1 log compared to treatment with tap water (TW). Hardness differences on storage were observed. However, reduction in PPO activity by electrolyzed water was not reproducible. Changes in Hunter's color value and the color difference value ($\Delta$) of peeled lotus roots immersed in 0.5% (w/v) sodium metabisulfite (SMS) and electrolyzed water were smaller than those of roots treated with TW prior to storage. Sensory characteristics measured during storage were best-preserved in lotus roots previously immersed in 0.5% (w/v) SMS or electrolyzed water, compared to TW. Immersionin electrolyzed water and vacuum packaging preserves the quality of peeled lotus roots in terms of microbial, visual, and sensory aspects, at levels comparable to those offered by storage after treatment with 0.5% (w/v) SMS.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.2
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• pp.143-149
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• 2022

PCS needs to freely switch AC and DC to connect the battery, external AC loads and renewable energy in both directions for energy efficiency. Whenever converting happens, power loss inevitably occurs. Minimization of the power loss to save electricity and convert it for usage is a very critical function in PCS. PCS plays an important role in the ESS(Energy Storage System) but the importance of stabilizing semiconductors on PCB(Printed Circuit Board) should be empathized with a risk of failure such as a fire explosion. In this study, the temperature variation inside PCS was reviewed by cooling fan on top of PCS, and the vibration characteristics of PCS were analyzed during truck transportation for reliability of the product. In most cases, a cooling fan is mounted to control the inner temperature at the upper part of the PCS and components generating the heat placed on the internal aluminum cooling plate to apply the primary cooling and the secondary cooling system with inlet fans for the external air. Results of CFD showed slightly lack of circulating capacity but simulated temperatures were durable for components. The resonance points of PCS were various due to the complexity of components. Although they were less than 40 Hz which mostly occurs breakage, it was analyzed that the vibration displacement in the resonance frequency band was very insufficient. As a result of random-vibration simulation, the lower part was analyzed as the stress-concentrated point but no breakage was shown. The steel sheet could be stable for now, but for long-term domestic transportation, structural coupling may occur due to accumulation of fatigue strength. After the test completed, output voltage of the product had lost so that extra packaging such as bubble wrap should be considered.

• Food Science and Preservation
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• v.2 no.2
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• pp.285-291
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• 1995

This study was performed to investigate the optimum moisture content and the best packaging method of dried persimmons for long term storage at room temperature. The package material to be used were 0.05mm polyethylene film, Wrap film, 0.08mm LDPE film exchanged nitrogen gas, and non package for untreated control. Before the storage, the initial moisture contents of dried persimmons were treated with 40%, 35% and 30%, respectively; 40% as traditional dryness, 35% as extending dry period one more week, and 30% as for two more weeks. The best package method was 0.08mm LDPE film exchanged nitrogen gas, and the optimum moisture control was 35%

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1308-1314
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• 1999

The effects of modified atmosphere(MA) packaging and coating on the quality of mushroom (Agaricus bisporus) were investigated. Whole mushrooms(100 g) were packed with polyvinyl chloride(PVC) film wrap, PD941 and PD961 film bags and were stored in a chamber at $12^{\circ}C$ and 80% RH for 6 days. Gas composition of packages, respiration rate, weight loss, color and maturity index of MA packaged mushrooms were examined. The wrap packaged mushrooms showed different level of internal $CO_2$ concentrations among water washed, chitosan coated and $CaCl_2$ coated subgroups significantly at 5% level. The maximum $CO_2$ concentration of PD941 and PD961 packages for all coated showed $4.1{\sim}4.7%$ and $10.4{\sim}11.7%$, respectively, for the first day. PD961 package showed the lowest $O_2$ concentration compared to other groups. There were no significant respiration rate differences between wrap packed and PD941 packaged. Respiration rate of water washed. chitosan coated and $CaCl_2$ coated in PD961 packaged was 192 mg, 226 mg and 245 mg, respectively. Maturity index of PD961 packaged were not significantly different among the water washed, chitosan and $CaCl_2$ coated packages. Chitosan coating showed a negative effect on color change of mushrooms. The weight loss of 961 packaged was lower $(7.0{\sim}8.0%)$ that those of wrap packaged and PD941 packaged.