• Korean Journal of Food Science and Technology
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• v.36 no.5
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• pp.733-739
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• 2004

Model for optimally dimensioned PE film bag was developed according to fruit size to maintain best quality of 'Fuyu' persimmon in modified atmosphere packaging (MAP) storage based on relationship between quality and oxygen and carbon dioxide in PE film bag. Harvested persimmons were graded into five sizes, and average weights were LL:261, L:217, M:188, S:168, and SS:154 g. Five fruit units of each grade were optimized in five PE film bag sizes of $150{\times}376,\;140{\times}357,\;130{\times}344,\;130{\times}333,\;and\;120{\times}3l8\;mm$. To minimize quality deterioration such as softening and discoloration, optimal oxygen and carbon dioxide concentrations in PE film bag were 0.5-1.0 and 6.0-8.0%, respectively, and optimal thickness of PE film bag according to fruit size were LL:45, L:50, M:55, S:60, and $SS:65\;{\mu}m$. For all fruit sizes, model for PE film bag area $(mm^2)$ was good quadratic simple equation by fruit weight (g): $Y=-4055.707+627.993X_1-0.701{X_1}^2$. Model far optimal oxygen and carbon dioxide (Y) concentration in PE film bag was suited to linear multiple equation by fruit weight $(X_1,\;g)$ and PE film thickness $(X_2,\;{\mu}m)$. Equations for oxygen and carbon dioxide concentrations (%) were $Y=5.798-0.0109X_l-0.0491X_2\;and\;Y=-2.427+0.01927X_l +0.09646X_2$, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.2
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• pp.283-287
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• 1996

건멸치의 품질안정성 연구를 위하여 접합필름(nylon $15\mu\textrm{m}/polyethylene$ $100\mu\textrm{m})으로$ 포장된 시료에 감마선을 조사한 다음 상온과 $저온(5~10^{\circ}C)에$ 1년간 저장하면서 미생물학적 및 관능적 품질을 평가하였다. 건멸치에 오염된 미생물의 방사선감수성은 위생지표 미생물>호염성세균>효모 및 곰팡이의 순으로 나타났으며, 5kGy 범위의 감마선 조사는 저온 및 상온에서도 미생물학적 품질을 1년 이상 유지할수 있었다. 관능적품질에 있어서 시료의 겉모양(갈변)과 맛 기호성은 10kGy의 고선량 조사시 대조군보다 유의적으로 저하되었다(p<0.05). 접합필름 포장시료를 5kGy 조사하여 상온과 저온에 1년간 저장하였을 때 관능적 품질은 저장온도별로 유의적인 차이가 나타났으며(p<0.01), 상온에서는 6개월 이상, 저온에서는 1년 이상 상품성 유지가 가능하였다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.417-422
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• 1999

Algin and chitosan are known as biodegradable natural polymers. PVA is useful for the production of water soluble packaging, paper, textile sizes. PVA/Algin and PVA/chitosan films were prepared by solution blends method in the weight ratio of chitosan, algin for the purpose of useful biodegradable films. Thermal and mechanical properties of blend films such as DSC, impact strength, tensile strength and morphology by SEM were determined. As a result, The ratio of 10.0wt% PVA/chitosan films were similar to PVA at thermal and mechanical properties. PVA/Algin films were found that phase separation was occured as more than 25wt% increasing the blend ratio of algin. PVA/Algin films were observed to be less partially compatibility than 10wt% increasing the blend ratio of algin by DSC, mechanical properties and SEM. Blend films were completely degraded pH 4.0 better than 7.0, 10.0 in the buffer solution. Also, they were rapidly degraded in the enzyme( glucosidase) solution better than pH solution by enzymolysis.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.713-717
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• 1994

Effects of packing materials on the gas compositions in package of fresh peeled garlic (Allium sativum L.) were investigated. The fresh peeled garlics packed in $20,\;40,\;60\;{\mu}m$ LDPE and $30\;{\mu}m$ HDPE pouches were stored at $20^{\circ}C$, 76% RH. The variables including respiration characteristics, gas compositions, general appearance, and film permeabilities to $O_2$, $CO_2$ and $H_2O$ vapor were measured. A model was evaluated for the prediction of $O_2$ and $CO_2$ equilibrium concentrations inside packages and for the optimization of packaging parameters. Experimental and simulated gas composition results were found to be in good agreement. The $30\;{\mu}m$ HDPE pouch with 4% $O_2$ and 7.5%$CO_2$ equilibrium concentrations conferred the best appearance of peeled garlic, giving 6 days of storage life. As a result, MA seemed to have a beneficial effect on appearance of fresh peeled garlic, possibly due to reduced microbial activity.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.659-667
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• 2000

Quality attributes of fresh-cut green onion(Allium fistulosum L.) as affected by rinsing and packaging were investigated in terms of flesh weight, color, viable cell counts, sensory properties during storage at $10^{\circ}C$. Fresh green onions were trimmed, cut, and rinsed with cold water(approximately $5^{\circ}C$) as well as chlorine solution(100 mg/L) and then packaged in low density polyethylene film pouches of $63\;{\mu}m$ thickness. Rinsing treatments with cold water or chlorine solution did not significantly influence changes in microbial populations but sensory characteristics, resulting in cut green onions of better visual quality as compared to the control without rinsing. Fresh-cut green onions were also rinsed with cold water and packaged in sealed bags of low density polyethylene films with different thickness(22, 36, $63\;{\mu}m$), and stored at $10^{\circ}C$ for 18 days. Thickness of polyethylene film was a significant factor for microorganisms populations and sensory attributes. Mesophilic aerobic bacterial count after 13 days for the control, packed in punched film bags, was $3.07{\times}10^6}$ CFU/g, while those for samples in hermetically sealed bags ranged only $1.74{\sim}2.02{\times}10^5}$ CFU/g. Gas composition within the sealed packages changed from normal air to about $1.3{\sim}5.4%\;O_2$ and $4.0{\sim}8.0%\;CO_2$ after 13 days of storage. Particularly, the visual sensory quality of cut green onion samples was retained better in polyethylene film bags of $63\;{\mu}m$ thickness(gas transmission rate: 600 $O_2\;mL/day{\cdot}m^2{\cdot}atm;\;2,500\;CO_2\;mL/day{\cdot}m^2{\cdot}atm$) than in the others.

• Food Science and Preservation
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• v.11 no.4
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• pp.478-484
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• 2004

Freshness maintenance of polyethylene packaging film containing surface-modified zeolite was investigated depending on the nature of substituted cations and cationic surfactants. Freshness maintenance was designed to work by cation or cationic surfactant adsorbed onto the zeolite surface by ion-exchange method. Cationic surfactants such as DODAB (n-dodecyltrimethylammonium bromide), CTAB (n-cetyltrimethylammonium bromide), and DHAB (n-dihexadecyldime-thylammonium bromide), and cations ($Ce^{3+},\;Al^{3+},\;Mg^{2+},\;Ca^{2+},\;Ag^{3+},\;Na^{1+}\;and\;Cu^{3+}$) were used. Surface-modified zeolite powder was compounded with LDPE to produce $20\;wt\%$ zeolite masterbatch (M/B), and the M/B was again blended with LDPE to get zeolite-containing LDPE films with 3, 5, $10\;wt\%$ of zeolite (width: 40 cm, thickness: $40\;{\mu}m$). Mechanical properties of zeolite-containing LDPE films generally decreased with increasing zeolite content. However, cationic surfactant-modified zeolite film showed the better mechanical properties compared to cation-modified zeolite film. As for the freshness maintenance, the zeolite-containing films modified with cationic surfactants or cations ($Al^{3+},\;Ag^{3+}$) showed the best performance.

• Food Science and Preservation
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• v.31 no.1
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• pp.126-137
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• 2024

In this study, zinc oxide nanoparticles (ZnONPs) were synthesized using three distinct zinc salts: zinc acetate, zinc chloride, and zinc nitrate. These ZnONPs were subsequently utilized in the fabrication of carrageenan-ZnONPs (Car-ZnONPs) composite films. The study assessed influence of the various ZnONPs on the morphological, water vapor barrier, color, optical, and antimicrobial properties of the Car-ZnONPs composite films. The surface morphology and UV-blocking attributes of the composite films were affected by the type of ZnONPs used, but their surface color, transparency, and chemical structure remained unaltered. The composite film's thickness and elongation at break (EB) significantly increased, while the tensile strength significantly decreased. In contrast, film's elastic modulus (EM) and water vapor permeability coefficient (WVP) showed no significant difference. All the composite films with added ZnONPs demonstrated potent antibacterial activity against Escherichia coli O157:H7 and Listeria monocytogenes . Among the carrageenan-based composite films, Car-ZnONPs^ZC showed the highest antibacterial and UV-blocking properties, and its elongation at break was significantly higher than that of the pure carrageenan films. This suggests that ZnONPs composite films have the potential to be used as an active packaging film, preserve the safety of the packaged food and extend shelf life.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.24 no.3
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• pp.97-106
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• 2018

This study aimed at examining the suitability of $Tenax^{(R)}$ for the migration testing of food packaging materials, which is currently approved in the EU as a dry food simulant. The results are used as a basis to examine the feasibility of introducing $Tenax^{(R)}$ to Korean regulation. The OMVs of test specimen into various solvents (diethyl ether, ethanol, pentane, and acetone) after exposure to $100^{\circ}C$ for 1 hr were compared. Diethyl ether showed the highest OMV ($1.33mg/dm^2$) among the solvents tested. When the tests were conducted with different amounts of $Tenax^{(R)}$ of 2, 4, or 8 g per specimen, the OMVs were 0.75, 1.33 and $1.40mg/dm^2$, respectively. The OMV obtained with a closed system after wrapping with aluminum foil showed a significantly higher OMV ($1.61mg/dm^2$) than that without aluminum wrapping ($1.318mg/dm^2w$) and an open system without lid ($1.06mg/dm^2$). The specific migration rates of surrogates spiked in the polyethylene test film and paper samples into $Tenax^{(R)}$ were compared with those into liquid food simulants including 95% ethanol and n-heptane, and actual foods such as starch, skim milk, and sugar. In general, the specific migration levels of surrogates into $Tenax^{(R)}$ were similar compared with n-heptane, however those were significantly higher than into actual foods. These results suggest that $Tenax^{(R)}$ may be used as a food simulant for the long-term preservation of dried foods and paper products. However, more studies need to be conducted to investigate the factors influencing the migration into $Tenax^{(R)}$, such as the types of foods and packaging materials tested, migration conditions, and surrogates properties etc.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1381-1387
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• 1998

Laminated films were prepared by casting corn-zein and fatty acid mixed solutions onto ${\kappa}-carrageenan$ films, and the effect of various fatty acids with different concentrations on the film properties such as water vapor permeabilities (WVP), tensile strength (TS) and elongation was investigated. WVP of the film decreased as concentration of fatty acids increased, and the lowest WVP value $(0.497\;ng\;m/m^2\;s\;Pa)$ was achieved with laminated films containing 30% lauric acid/corn-zein. The TS of laminated edible film seemed to decrease as the concentration of fatty acids increased, and TS of the laminated film was the highest (36.21 MPa) when the film contained 10% oleic acid. Weight loss of the minced mackerels packaged with corn-zein/carrageenan film which did not contain fatty acid was 11.7%, but weight losses of the samples packaged with oleic acid and lauric acid were 6.97% and 0.81%, respectively, after 30 days storage at $-20^{\circ}C$. The laminated films had an effect on preventing oxidation of the minced mackerels during storage because of high oxygen barrier property of the film. All of the minced mackerels packaged with the laminated films greatly reduced the peroxide value (POV) compared with unpackaged minced mackerels during storage. Also, thiobarbituric acid (TBA) values of the minced mackerels packaged with the laminated films were lower than that of unpackaged minced mackerels during storage.

• Food Science and Preservation
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• v.17 no.6
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• pp.908-913
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• 2010

Modified atmosphere packaging (MAP) was evaluated for the storage of pumpkin rice cake as a means of preserving quality and extending shelf-life. Retail-sized amounts of rice cake were packaged in trays under different modified atmosphere conditions (air, vacuum, 60% $CO_2$/40% $N_2$ and 100% $CO_2$) using gas-barrier plastic film; control was in air-permeable stretch wrap. The packages were stored at $20^{\circ}C$ with periodical measurement of package atmosphere and cake quality attributes. The modified atmosphere packages of 60% $CO_2$/40% $N_2$ and 100% $CO_2$ inhibited the growth of molds/yeasts completely and significantly retarded the growth of aerobic bacteria. All the packages except that of 100% $CO_2$ showed the reduction of internal $O_2$ concentration and increase of the $CO_2$ with storage time due to the microbial activity. There has been slight decrease of $CO_2$ concentration for 60% $CO_2$/40% $N_2$ and 100% $CO_2$ packages just after start of the storage possibly due to dissolution of headspace $CO_2$ into the cake. Any MAP conditions did not affect the retrogradation of the rice cake. Surface color of the cake within affordable microbial quality limit was not affected significantly by packaging conditions.