• Microbiology and Biotechnology Letters
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• v.23 no.6
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• pp.702-709
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• 1995

Degradation Of $\kappa $-carrageenan-based film by microorganisms screened from carrageenan source and activated sludge of a carrageenan producing factory was investigated by measuring changes of pH, viscosity, total sugar and total organic carbon (TOC) of the medium containing $\kappa $-carrageenan as a carbon source. Initially fifteen strains of microorganism were isolated from carrageenan source and activated sludge and then three organisms among them were selected based on the ability of growing in the medium including 0.3% $\kappa $-carrageenan as a sole carbon source. They were identified as Escherichia coli, Saccharomyces cerevisiae and Aspergillus niger. As indices of biodegradability Of $\kappa $-carrageenan based film, the changes of pH, viscosity, total sugar, and TOC of the carrageenan film-based medium were tested by the cultivation of single or mixed strains of the identified organisms. Mixed culture showed the highest biodegradability, which resulted in the changes of pH from 6.5 to 3.0, viscosity from 164 cps to 15.6 cps, total sugar content from 2.35 g/l to 0.53 g/l and TOC from 5721 ppm to 232 ppm after 30 days of cultivation. The biodegradability determined as the reduction rate of TOC by pure cultures of Asp. niger, E. coli, Sacch. cerevisiae and mixed culture of the three organisms were 94%, 86%, 80% and 96%, respectively.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.26 no.3
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• pp.125-131
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• 2020

Carrageenan-based functional films were prepared by adding two different types of sulfur nanoparticles (SNP) synthesized from sodium thiosulfate (SNPSTS) and elemental sulfur (SNPES). The films were characterized using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction spectroscopy (XRD), and thermal gravimetric analysis (TGA). Also, film properties such as UV-visible light transmittance, water contact angle (WCA), water vapor permeability (WVP), mechanical properties, and antibacterial activity were evaluated. SNPs were uniformly dispersed in the carrageenan matrix to form flexible films. The addition of SNP significantly increased the film properties such as water vapor barrier and surface hydrophobicity but did not affect the mechanical properties. The carrageenan/SNP composite film showed some antibacterial activity against foodborne pathogenic bacteria, L. monocytogenes and E. coli.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.855-861
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• 1998

Composite films based on ${\kappa}-carrageenan$ and chitosan were prepared, and tensile strength (TS), elongation (E), and water vapor permeability (WVP) of the films were measured. The molecular weight of ${\kappa}-carrageenan$ and chitosan was measured by a light-scattering instrument and was $5.1{\times}10^5,{\;}and{\;}1.71{\times}10^5$, respectively. TS of ${\kappa}-carrageenan$ and chitosan free film was 30.2 MPa and 21.0 MPa, respectively. TS of composite film was not related to the amount of the ascorbic acid. E of composite film was lower than those of the free films of ${\kappa}-carrageenan$ and chitosan. WVP of composite film was lower than that of chitosan film and was similar to WVP of ${\kappa}-carrageenan$ film.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.390-393
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• 1997

${\kappa}-Carrageenan-based$ film prepared by mixing 2% ${\kappa}-carrageenan$, 0.1% KCl, 0.75% polyethylene glycol, and 0.75% glycerol was examined to be used as a potential packaging material for mackerel mince for preventing moisture loss and lipid oxidation. Mackerel mince patties were vacuum-packaged with the film and stored at $20^{\circ}C,\;10^{\circ}C,\;0^{\circ}C,\;and\;-15^{\circ}C$; nonpackaged patties were also stored at $0^{\circ}C$. Weight reduction, peroxide value (PV), and thiobarbituric acid (TBA) value were measured during storage. The packaged or nonpackaged samples stored at $20^{\circ}C,\;10^{\circ}C,\;and\;0^{\circ}C$ showed a 60% weight reduction between 2 and 15 days of storage, while the weight reduction of the samples stored at $-15^{\circ}C$ was about 3% after 25 days. The nonpackaged samples stored at $0^{\circ}C$ showed a steady increase in lipid oxidation with the PV reaching 23 mequivalent peroxide (PO)/㎏ on day 20 and with the TBA value at 0.4 mole malonaldehyde (MA)/g on day 5. The PV and TBA values of the samples vacuum-packaged with the carrageenan-based film were below 2 mequivalent PO/㎏ and below 0.1 mole MA/g, respectively, regardless of storage temperature throughout the storage of 28 days.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.379-384
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• 1998

Biodegradable carrageenan films and carrageenan-coated papers were developed and their characteristics of lipid permeation was investigated for possible substitution of PE-coated papers used in packaging of oily or greasy foods. Both carrageenan coated papers and free carrageenan films were highly resistant to lipid penetration. Among the carrageenans tested, ${\kappa}-carrageenan$ film showed the most resistant followed by ${\lambda}-$ and i-carrageenan films. The resistance to lipid increased as the thickness of ${\kappa}-carrageenan$ layer increased. Carrageenan coated papers with $4\;and\;5\;kg/ream\;(278m^2)$ showed the lipid resistance comparable to that of the PE-coated paper. Free films also showed the same trends of the lipid resistance as the carrageenan coated papers, but the degree of lipid resistance was approximately ten times higher than that of carrageenan coated paper. Degree of lipid penetration of carrageenan films and carrageenan-coated papers increased exponentially against time. ${\kappa}-carrageenan$ coated papers over 4 kg/ream showed to have an adequate lipid barrier property for being utilized for packaging greasy food products.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.545-551
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• 1996

Water-vapor transmission rate and water-vapor permeability of carrageenan-based edible film with three different thicknesses of 0.05, 0.08 and 0.11 mm were measured to investigate the potential applicability of the films to powder foods at five different temperatures (20, 25, 30. 35 and $4^{\circ}C$) and three different relative humidities (50. 70 and 90% RH). Water-vapor transmission rate of the carrageenan-based film was gound to be 2.3 times higher than that of polyethylene (PE) film and water-vapor permeability of the film was 45-230 times higher than that of PE film. Water-ydpor permeability of the film seemed to increase linearly with the film thicknees like other hydrophilic edible films. Water-vapor transmission rate were found to be dependent on the temperature. Activation energies of the water-vapor transmission rate of the film were found to be between 7.898 and 12.8702 kj/mol depending on the film thickness. The water-vapor transmission rate of the film showed the typical kinetic compensation effect between activation energies and preexponential factors. which was proved by the linear increase in the value of logarithms of preecponential factor.

• Food Science of Animal Resources
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• v.33 no.1
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• pp.53-57
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• 2013

This study was performed to examine the possibility of water extracts for several medicinal plants, such as Amomum tsao-ko, Alpinia oxyphylla, and Citrus unshiu, as an active packaging ingredient for prevention of lipid oxidation. Chicken breast meats were packed with medicinal plant extracts incorporated carrageenan based films and their physico-chemical and microbial properties during storage at $5^{\circ}C$ were investigated. In chicken meat samples packed with A. tsao-ko (TF) or A. oxyphylla (OF) extract incorporated carrageenan based films, pH value, thiobarbituric acid reactive substances (TBARS), and the population of total microbes were significantly lower than those of the negative control (film of no extract was incorporated, CF) after 5 d of storage (p<0.05). Especially, TBARS value of TF ($0.12{\pm}0.01$ mg malonaldehyde/kg meat) was significantly lower than chicken meat samples packed with positive control (ascorbic acid incorporated film, AF, $0.16{\pm}0.01$ mg malonaldehyde/kg meat) at 3 d of storage, and it means TF has enough antioxidative activity to prevent the lipid oxidation of chicken meat. However, there was no consistent effect on VBN values of chicken meats packed with medicinal plant extracts incorporated films during storage. Based on the obtained results, it is considered that A. tsao-ko extract has potential for being used as a natural antioxidant ingredient in active packaging areas.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.1 no.1
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• pp.38-50
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• 1995

Tensile strength (TS) of ${\kappa}-carrageenan$ films without salt was 22-32 MPa and was the highest among ${\kappa},\;{\lambda}\;and\;{\iota}-carrageenan$ films. ${\kappa}-carrageenan$ films had high mechanical barrier properties as they are compared with TS of polyethylene films which are 13-28 MPa. TS of ${\iota}-carrageenan$ films without salt was 5-9 MPa and was the lowest among the films. Mechanical properties (TS and elongation) were affected by the concentration of plasticizers. Especially, elongation of ${\kappa}-carrageenan\;and\;{\iota}-carrageenan$ drastically increased as the concentration of plasticizer increased. Mechanical properties (TS and elongation) were greatly affected by various concentration and kind of salts. TS of Film-A (0.375 g plasticizer/g carrageenan) of ${\kappa}-carrageenan$ films which contains 0.1% (w/w) potassium chloride increased to 45 MPa which was the highest among the TS of biopolymer films which have been developed.

• 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 Food Science and Technology
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• v.30 no.2
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• pp.363-371
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• 1998

Locust bean gum (LBG)-based edible film was prepared, and opacity, water vapor permeability (WVP), tensile strength (TS) and elongation (E) of the film were measured. Opacity values of the film was a little higher than that of other transparent films. WVP decreased as LBG concentration decreased. Plasticizers and drying temperature didn't seem to influence WVP. WVP of the film increased greatly at 85% RH as compared to that of 0% RH. WVP of the film seemed to increase linearly with thickness of the film. But WVP of the film was lower those of other edible films. TS increased with increase of LBG concentration, and decreased with increase of glycerol concentration. E decreased with increase of LBG concentration, and increased with increase of sorbitol concentratin. LBG-based composite films were prepared by adding agarose, k-carrageenan or xanthan gum. TS and E of the composite film with addition of k-carrageenan increased.