• KSBB Journal
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• v.17 no.4
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• pp.350-356
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• 2002

Low density polyethylene(LDPE) film was fabricated with the addition of benzoic acid, or/and JP which contained water-soluble silica adsorbed a natural antimicrobial compounds. The used antimicrobial compounds were isolated from culture broths of methylotropic actinomycetes strains MO-16 and MO-17 which was newly isolated from soils. An antimicrobial compound retained antimicrobial activity after heat treatment at 121$^{\circ}C$ for 5 min. JP, which obtained from Japan as a antimicrobial agent, showed antimicrobial activity in the concentration of 100 mg/mL. The silica LDPE film revealed the growth inhibition of total aerobic bacteria in packaged minced pork compared with commercial film and of E. coil on a contained agar plate. In the storage testing of various packaged foods at room temperature for 30 days, the film showed excellent preservation compared with commercial film in case of small tomato and Agaricus bisporus.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.4
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• pp.621-628
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• 2002

Effect of the thickness of packaging film on the ripening of mature-green mume (Prunus mume Sieb. et Zucc) fruit was investigated by measuring physicochemical changes of the fruit during storage. Fruits were packaged using low density polyethylene (LDPE) films with thicknesses of 20, 30, and 40$\mu$m and stored at the room temperature. The physicochemical properties such as contents of various pectic substances, molecular weight distribution of soluble pectic substances, and surface image of the fruit were determined during storage of 8 days. In general, regardless of the thickness of the films applied, a content of water-soluble pectin (WSP) in the fruit was increased during storage, but both contents of HCI- soluble pectin (HSP), and Ca and Mg in total alcohol-insoluble solids were decreased. Sephacryl S-300 gel filtration study revealed that fractions of high molecular weight HSP and WSP decomposed into lower molecular weight pectins during storage. The scanning electronic microscope also identified a significant structural change of the fruit skin over the storage time. It could be concluded from the results that fruits packaged with LDPE 30${\mu}{\textrm}{m}$ film maintained the highest physicochemical quality of green mume fruit during storage.

• Food Engineering Progress
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• v.15 no.3
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• pp.257-261
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• 2011

Biodegradable plastics were developed using biodegradable pellets made of corn stalk and rice husk and their safety as food packages and their biodegradability against light (ultraviolet (UV)), heat, and fungi were evaluated. Four kinds of 50-${\mu}m$ biodegradable plastics were produced by extruding the mixtures of the biodegradable pellets, low-density polyethylene (LDPE), high-density polyethylene (HDPE), and linear low-density polyethylene (LLDPE) with different compositions. Developed biodegradable plastics were safe to be used as food packages. The initial tensile strength and percentage elongation of the plastics were similar to those of LDPE, but the values decreased with increased their exposure time to UV and heat. The fungal biodegradability of the biodegradable plastics was higher than that of LDPE. The biodegradability of the biodegradable plastics shows the potential for them to be used as sustainable food packages.

• Food Science and Preservation
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• v.10 no.1
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• pp.16-22
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• 2003

This study was conducted to find out effective MA (Modified Atmosphere) gas compositions on the oyster mushroom through statistical analysis of the respiration rate and MA storage for the various packaging materials. Under the various gas compositions, the oxygen consumption rate of oyster mushroom was from 28.9 to 161.4mgO$_2$/kg$.$hr and the carbon dioxide evolution rate was from 53.4 to 166.9 mgCO$_2$/kg$.$hr at 20$^{\circ}C$. The estimated MA condition of oyster mushroom were 2.5∼4.5%O$_2$and 11.5∼l3%CO$_2$by the RSREG(Response Surface Regression). The gas compositions of MA packaging are following that 0.03mm LDPE were 1.6∼3.0%O$_2$and 3.9∼5.3%CO$_2$,0.05mm LDPE were 1.2∼1.3%O$_2$and 9.0∼11.1%CO$_2$and Nylon+PE were 0.9∼1.2%O$_2$and 33.5∼39.6%CO$_2$. The weight loss increased at 0.03mm LDPE but has the lowest value at Nylon+PE. The hardness of pileus and stipe was decreased with storage periods. The $\Delta$E-value increased with storage period and seriously changed in early storage period at 12 and 20$^{\circ}C$. In the 0.05mm LDPE, the gas compositions of packaging were similar to estimated gas compositions from the RSREG and the storage quality was superior to the other packaging materials in weight loss, hardness, and color difference at 4, 12 and 20 $^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.80-84
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• 2000

To investigate the effect of packaging condition on functional MA films laminated (30CE, 50CE), corrugated paperboard box (control), 30LDPE, and 50LDPE pouches on the freshness extension of Fuji apples, the weight loss, firmness, total ascorbic acid, titratable acidity, soluble solids content and appearence were evaluated at 5$^{\circ}C$ after 75 days. Weight loss of 30CE and 50CE, and 30LD and 50LD was 0.4 to 0.5%, and 0.2%, but control was 2.7%. Firmness in film packages was higher than that of control, and CE packagings were higher than LD. Total ascorbic acid content of Fuji apple in control after 75 days was 2.12 mg%, that of control was decreased by 42%, those of LD packagings were 31% and 29%, and those of CE were 24% and 22%. Titratable acidity and soluble solids content in control changed more than that of MA film packagings. Overall appearence of 'Fuji' apples in CE packagings was better than that of control.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.1
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• pp.182-188
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• 2008

The compounds of recycled polyethylene(PE) and fly-ashes were prepared. Polymers used were sorted PE from mixed plastics of household waste and Low Density Polyethylene(LDPE) and Linear Low Density Polyethylene(LLDPE) recycled from the scrap of packaging film plants. Fly-ashes were from the power plant and from the household waste incinerator. The tensile strength of recycled LDPE and LLDPE compounds decreased and the flexural modulus increased with greater amount of the power plant fly-ash. Anthracite fly-ash gave rise to slightly higher tensile and flexural strength of the LLDPE mixtures than bituminous coal fly-ash presumably due to higher content of unburned carbon. The incinerator fly-ash introduced to household waste PE enhanced both tensile strength and flexural modulus of the compounds. When LDPE and household waste PE were used together, the synergistic effect of incinerator fly-ash to household waste PE was offset by reduced crystallization of LDPE due to the filler particle. The compounds of household waste PE and incinerator fly-ash might be applied to structural materials for such as sewage pipe, which reduces the waste treatment cost and conserve the environment and resources.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.3
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• pp.125-132
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• 2017

The effect of food simulants on properties and light barrier function of LDPE-nano $TiO_2$ composite film has been investigated. LDPE-nano $TiO_2$ composite films were prepared with 5.0wt% $TiO_2$ content by melt-extrusion. To simulate food contact environment, according to KFDA standards and specifications for food utensils, containers and packages, food simulants were selected with deionized water, 50% ethanol, 4% acetic acid and n-heptane and composite films were immersed in each food simulant at $70^{\circ}C$, 30 min except n-heptane ($25^{\circ}C$, 60 min). A variety of material properties, including crystallinity, chemical bonds, surface morphology, mechanical, oxygen barrier and optical properties, of LDPE-nano $TiO_2$ composite film were examined with and without the food simulants treatment. As a result, under regulated migration condition, LDPE-nano $TiO_2$ composite showed extremely stable in all properties tested in the study in contact with food simulants indicating that $TiO_2$ nanoparticles are physicochemically stable and quite compatible with LDPE. Results enable us to anticipate migration of $TiO_2$ will probably not occur. To evaluate influence of migration of $TiO_2$ on food stuffs, their color, pH and acidity were observed as well.

• Food Science and Preservation
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• v.5 no.4
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• pp.335-338
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• 1998

Weight loss of fear packed with corrugated paperboard box(FC) laminated with functional MA film after 60 days storage at 5$^{\circ}C$ was 1.0%, and that of LDPE, CE film was 0.6-0.7%, while that of control(Corrugated Paperboard box) was 2.8%. Total ascorbic acid content of pear ill MA films and FC package was higher than that of control. Titratable acid of control changed 37%, but that of the others packages changed below 27%. Soluble solid content of control changed 27%, while the others changed below 2%. Reference in overall appearence of pear were not found among packaging methods. Corrugated paperboard box(FC) laminated with Functional MA film can be used as packaging material for pear packaging.

• Korean Journal of Human Ecology
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• v.9 no.4
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• pp.505-512
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• 2000

The fresh ginseng was packed individually with a soft film bag, ONY/LDPE/L-LDPE (20$\times$30 cm, 93 ${\mu}m$) and stored at $25^{\circ}C$ for twenty days. The Quality-related appearance parameters and the sensory characteristics of the fresh ginseng were evaluated. The quality of the fresh ginseng was lowered mainly due to hardness decrease with increasing storage time, while the occurrence of mould was rarely observed. The normal ginseng had strong fresh ginseng odor and strong bitter taste and its hardness was well maintained during twenty days. The softened ginseng had pungent and sour odor, sweet and sour taste and sticky texture.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.17 no.1
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• pp.13-17
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• 2011

There is a need in food industry to store minimally processed garlic for long time to have it be used just at the time of demand for final product processing. Optimal modified atmosphere packaging is expected to slow down the quality change extending its storage life. In order to find optimal packaging conditions, plastic films of different gas permeability properties (low density polyethylene (LDPE) $30{\mu}m$, polyolefin $50{\mu}m$ (PD 900), polyolefin $20{\mu}m$ (PD 941)) were used for packaging 400 g of minimally processed garlic. Perforated LDPE packages were prepared as control. The packaged products were stored at $1{\pm}1^{\circ}C$ for 52 days. Package treatments were compared in weight loss, decay, surface color, hardness and soluble solid content. While control package had normal atmosphere of air, LDPE, PD 900 and PD 941 packages attained internal concentration of $O_2$ 4.6% / $CO_2$ 12%, $O_2$ 0.9% / $CO_2$ 21% and $O_2$ 0.5% / $CO_2$ 13% after 45 days, respectively. Control packaging had rapid weight loss with high mold decay and great surface color change in 45 days. In PD 900 film packages of lowest gas permeability, the fresh-cut garlic could be stored without mold decay for 52 days. Except control packaging, there were no significant differences in surface color, hardness and soluble solid content among package treatments.