• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.6
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• pp.1063-1067
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• 2004

To elucidate the effect of protein films containing an antioxidant on lipid oxidation of fish paste products during storage, zein and soy protein isolate (SPI) films containing green tea extract were prepared and their physical properties were examined. Tensile strength and elongation of the protein films decreased by the addition of green tea extract compared to the control. Due to the addition of green tea extract, SPI film had an increase in yellowness, but zein film had a decreased yellowness. Wrapping of fried fish paste products by the zein and SPI films containing the antioxidant retarded lipid oxidation at 2 day storage by 3.6 mg MDA/kg sample and 3.6 mg MDA/kg sample, respectively, for instant fish paste compared to the control. For processed fish paste, they decreased the degree of lipid oxidation by 1.6 mg MDA/kg sample and 0.6 mg MDA/kg sample, respectively.

• Preventive Nutrition and Food Science
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• v.10 no.1
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• pp.88-91
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• 2005

To improve the physical properties of protein films, various plasticizers and cross-linking agents were used in the preparation of the films. For zein film, 3% polypropylene glycol with 3% glycerol was the best plasticizer, while 2.5% glycerol was the most suitable for soy protein isolate (SPI) film in terms of tensile strength (TS), % elongation, and water vapor permeability (WVP). Formaldehyde, glutaraldehyde, glyoxal, and cinnamaldehyde as cross-linking agents of protein films were used to further improve the physical properties of the films. All aldehydes used as cross-linking agent in this study improved TS of zein and SPI films. In particular, cinnamaldehyde was the best cross-linking agent due to its safety in foods. These results suggest that appropriate use of plasticizer and cross-linking agent like cinnamaldehyde should improve the physical properties of protein films for use in food packaging.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.1 s.113
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• pp.45-53
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• 2006

This study was carried out to produce high functional and biodegradable coating agents for pulp mold by evaluating various kinds of biodegradable polymers. Five kinds of biodegradable polymers were used. In addition, the mixture of the carboxymethylated starch and biodegradable polymers(${\kappa}$-carrageenan, chitosan) were used for mixed coating agents. Physical properties of coated paperboards were evaluated. Conclusions obtained were as follows. 4% ${\kappa}$-carrageenan and 5% chitosan showed higher water and oil resistance. 10% sodium alginate, 4% corn zein and 15% polycaprolactone showed high water resistance while no improvement was found on oil resistance. The optimum mixture ratios for the mixed coating agents were 90:10(carboxymethylated starch : ${\kappa}$-carrageenan) and 50:50(carboxymethylated starch : chitosan). Since these mixed coating agents have excellent biodegradability with higher water and oil resistance, these can be used for the environmental-friendly coating agents.

• Journal of Plant Biotechnology
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• v.36 no.1
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• pp.87-95
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• 2009

The recombinant DNAs, pGBF, pGTF, and pZ4F, using soybean ferritin gene have constructed with the promoters derived from seed proteins, glutelin, globulin, and zein. The recombinant ferritin genes were transformed into rice plant by Agrobacterium-mediated transformation. Iron contents and agronomic traits have been evaluated in the transgenic progenies. The embryogenic calli survived from second selection medium were regenerated at the rates of 19.2% with pGBF, 15.0% with pGTF, and 18.4% with pZ4F in Donganbyeo and 6.7% with pGBF, 11.7% with pGTF, and 3.4% with pZ4F in Hwashinbyeo. The introduction of ferritin gene in putative transgenic rice plants was confirmed by PCR and Southern blot analysis and also the expression of ferritin gene was identified by Northern blot and Western blot analysis. The iron accumulation in transgenic rice grains of the transgenic rice plant, T1-2, with zein promoter and ferritin gene contained 171.4 ppm showing 6.4 times higher than 26.7 ppm of Hwashinbyeo seed as wild type rice, but the transgenic plants with globulin and glutelin showed a bit higher iron contents with a range from 2.1 to 3.0 times compare to wild type grain. The growth responses of transgenic plants showed the large variances in plant height and number of tillers. However, there were some transgenic plants having similar phenotype to wild type plants. In the T1 generation of transgenic plants, plant height, culm length, panicle length, and number of tillers were similar to those of wild type plants, but ripened grain ratio ranged from 53.3% to 82.2% with relatively high variation. The transgenic rice plants would be useful for developing rice varieties with high iron content in rice grains.

• 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.

• Applied Biological Chemistry
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• v.38 no.3
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• pp.224-231
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• 1995

To increase the expression of a foreign protein in transgenic plant, the benefits of 5'-untranslated leader sequences of tobacco mosaic virus (TMV) RNA or soybean glycinin gene, Gy2, fused to a protein coding sequence were exploited. pGA643-derived plasmid contains 355 promoter of cauliflower mosaic virus, protein coding sequence of maize 10 kDa zein (10kZ) and Gy2 terminator. The leader from Gy2 or TMV RNA was inserted between the promoter and the coding sequence in each construct. The recombinant DNAs were introduced into tobacco plants by Agrobacterium mediated leaf disc transformation method. Although the transgene without the leader had more transcripts than the others, mRNAs containing the leader were translated more efficiently. It might be due to difference in the length of 5'-untranslated sequence and context surrounding the AUG codon, but could be sequence specific rather. These results suggest that the leader sequences of Gy2 and TMV play important roles as an enhancer in translational control of foreign gene in transgenic tobacco plant.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1033-1038
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• 2003

Four lines (MON810, GA21, NK603, and TC1507)of genetically modified maize(GMM) were recently approved after a safety-assessment by the Korea Food and Drug Administration (KFDA). In this study, five pairs of specific oligonucleotide primers, based on the gene sequences inserted into maize and zein gene as internal standards, were designed and a method using PCR was developed for monitoring GMM and GMM derived foods circulating in the market. MON810 and GA21 were detected in raw materials of feed and food in the Korean market.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.24 no.2
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• pp.41-48
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• 2018

A printable time temperature integrator (TTI) consisting of oxygen indicator and cover films with various oxygen permeability was developed. The printing ink contained methylene blue (oxygen indicator) which changed in color during storage. $TiO_2$ and glycerol for UV-activation of TTI and zein and ethanol for printing performance were also contained in the printing ink. The cover film on the ink was employed to control the color change rate and temperature dependency (Arrhenius activation energy, $E_a$) by using the different films (PE, PET, OPP, and LLDPE). The film properties were varied by annealing. TTI was produced by silk screen printing. As a result, the color change rates were different for the cover films, being the highest in TTI with LLDPE, followed by OPP, PE, and PET. The rate decreased with increase in the cover film thickness. The $E_a$ was the highest in TTI with LLDPE, followed by OPP, PE, and PET. The $E_a$ did not change with the cover film thickness. The annealed PVC and PET film were lower in oxygen permeability than the unannealed ones, indicating the lower color change rate.

• Korean Journal of Food Science and Technology
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• v.36 no.5
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• pp.842-846
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• 2004

To elucidate quality changes of pine nuts and walnuts coated with green tea extract-containing protein film during storage, pine nuts and walnuts were coated with soy protein isolate (SPI) and zein film containing green tea extract, and stored at $35^{\circ}C$ for 4 weeks. During storage, peroxide, acid, and 2-thiobarbituric acid (TBA) values increased with increasing storage time regardless of treatments. Degrees of lipid oxidation were lowest in protein coating containing green tea extract, followed by protein coating and control. After 4 weeks, for pine nuts, 40, 32, and 21% of peroxide, acid, and TBA values respectively decreased by treatment of zein film coating containing green tea extract compared with control. For walnuts, 29, 24, and 21% of peroxide, acid, and TBA values respectively decreased. With SPI film coating, 41, 36, and 8% of peroxide, acid, and TBA values of pine nuts respectively decreased. For walnuts, 26, 28, and 5% of peroxide, acid, and TBA values respectively decreased by treatment of SPI film coating containing green tea extract.

• Food Science and Preservation
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• v.14 no.4
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• pp.364-368
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• 2007

The purpose of this study was to improve the stability and the processing property of vitamin C. Vitamin C was coated according to particle size(80-100 mesh, 100-140 mesh) and mixing ratio(1:1.6, 1:2.5, 1:3(w/w)) with coating solution(8% Zein-DP, 6% HPMC-FCC), and then the quality characteristics of fluidized bed micro coated vitamin C were investigated. The coating efficiency and the thickness of coating film were higher in $80{\sim}100$ mesh particle than in $100{\sim}140$ mesh particles, and coating efficiency was decreased as the coating material was increased. The distribution range of particle was more narrow in mixing ratio of 1:3(w/w) than in the other. DPPH radical scavenging activity was not affected by the particle size and the mixing ratio. There was no difference between the coating materials in terms of the quality characteristics. The optimum coating condition for fluidized bed micro-coating of vitamin C powder was selected as the particle size of $80{\sim}100$ mesh and the mixing ratio with coating solution of 1:3(w/w).