• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.16 no.2_3
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• pp.59-65
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• 2010

Starch was modified with epichlorohydrin(ECH) to improve the miscibility with LDPE and LLDPE. Native starch or epichlorohydrin treated starch was mixed with grycerol and LDPE/LLDPE resin using a kneader and extruded using a single screw extruder to make pallets. The pallets were compression-molded at 145 into composite boards to evaluate their color, oxygen permeation, mechanical and thermal properties, and degradability under UV irradiation. Sheets with epichlorohydrin treated starch generally showed higher L-value than that of native starch blend sheets. The hunter b-values in both native starch blends and epichlorohydrin treated starch blends increased with Increasing starch contents. Tensile strength and percent elongation of sheets decreased with increasing starch contents. Tensile strength and percent elongation of sheets decreased with increasing starch contents. The degradability of blends under UV radiation increased with increasing starch contents in both blend types. The results represents that crosslinking of starch with epichlorohydrin may be a good method to improve miscibility of starch with petroleum-based materials.

• Polymer(Korea)
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• v.34 no.1
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• pp.58-62
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• 2010

The acrylic monomers were graft-polymerized to starch as matrix polymer by emulsion polymerization. Viscosity and particle size of the emulsion were increased with starch contents due to interaction with water and particle swelling toward the water phase by hydroxy group of starch. Chemical stability of the emulsion was also increased with enhancement of starch, but water and alkali resistance were reduced with increasing starch contents because of the increasement of hyrophilicity. Opacity of the starch-acrylic emulsion compound containing calcium carbonate was decreased with contents of starch by its intrinsic color. The film of starch-acrylic polymer showed more clear appearance with increasing starch contents owing to enhancement of amorphous state.

• Elastomers and Composites
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• v.43 no.4
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• pp.221-229
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• 2008

Starch as matrix polymer was used to do graft copolymerization with 2-ethylhexylacrylate, methyl methacrylate and acrylic acid. The polymerization was carried out by radical emulsion polymerization with increasing contents of starch. When 0.174% of $\alpha$-amylase as enzyme for starch was added, it was found that it made the best stable emulsion. The glass transion temperature of the polymerized material was increased with starch contents. The particle size and viscosity of the emulsion increased with starch contents due to the increased hydroxy group. Peel strength also increased with contents of starch because the enhanced hydroxy group caused to increase affinity between substrate surface and polymer materials. However, the initial tackiness decreased with starch contents owing to film hardness by higher glass transion temperature.

• Food Engineering Progress
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• v.21 no.4
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• pp.341-350
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• 2017

The relationship of in vitro starch digestibility and gel strength was investigated at various concentrations (10-30%) of rice cultivars with different amylose contents (27.9, 17.9, and 5.2%). As the rice flour concentration increased, predicted glycemic index decreased, but gel strength increased regardless of amylose contents. Gel strength correlated strongly with amylose content, whereas in vitro starch digestibility was more highly affected by rice flour concentration than by amylose contents. Moreover, the impact of degree of gelatinization on in vitro starch digestibility of high amylose rice was also examined in terms of structural features and rheological properties. The digestion rate of fully gelatinized flour was 1.7 times higher than that of native flour, while the disrupted structure with a different gelatinization degree during starch digestion was visually demonstrated through the X-ray diffraction and molecular distribution analysis. The rice flour changed from an A-type to a V-type pattern and showed difference in crystalline melting. The low molecular weight distribution increased with increasing degree of gelatinization during starch digestion. The apparent viscosity also increased with degree of gelatinization. These results demonstrated that the starch digestibility of rice was more affected by concentration than by amylose content, as well as by the degree of gelatinization due to structural difference.

• Journal of the Korean Society of Food Culture
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• v.22 no.1
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• pp.91-96
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• 2007

Developing carbohydrate fat replacer as materials for low-calorie and low-fat food made of Korean potato, it is expected that the new demand of fat replacer will be created. Potato starch was modified by chemical modification. Observing modified starch(treated in different method) by SEM, EZ(treated by enzyme) showed shape of deformed round oval, AC(treated by acetylation,), HPR(treated by hydropropylation) showed shape similar to that of NL(N-Lite), the commercial fat replacer. In the modified starch such as AC, peak in B and C type similar to those of general starch was found, but EZ showed non-crystalline shape. Compared to other modified starch, HPR, the chemically produced denatured starch showed very peculiar peak and structure in V-form. While the order of contents of amylopectin was in the order HPR > EZ > AC showed extremely high contents. Measuring the degree of gelatinization per the modified method, the degree of gelatinization of HPR as much higher than others. The water binding activity of modified starch was 240% in HPR. Measuring viscosity by producing general starch and modified starch as gel of 10% concentration, the CPS showed very high viscosity of 30.30 ${\times}$ 10$^3$ cp. Showing viscosity of 38.60, 31.60 10$^3$ ${\times}$ cp, the modified starch was in the order of HPR. While the calorie of starch of GPS was measured to be 3.0 Kcal/g, very low calorie those of chemically modified starch, HPR showed 2.5 Kcal/g respectively, suggesting that calorie is decreased by modified treatment. The appropriateness of processing food was experimented by substituting the existing oil and fat containing food with saturated gel of starch and modified starch in constant rate through utilization of modified starch. Therefore, research and development for materials and related products which maintain the existing quality and reduce fat contents will be constantly performed in the future.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.4
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• pp.52-64
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• 2013

This study was carried out to investigate the characteristics of starch paste which was used for the conservation of paper properties. Three kinds of commercial corn starch and five kinds of fermented wheat starch were examined on the contents of amylose and amylopectin, shapes of particles, and viscosity and pH of paste. And adhesive strength on the drying, accelerated aging, and wetting treatments were measured. The contents of amylopectin of oxidized corn starch were higher those of cationic corn starch, unmodified corn starch, and fermented wheat flour. In case of fermented wheat flour, increasing of a fermentation period was resulted in increasing of amylopectin contents. The particle shapes of commercial corn starch showed with a uniform polygon, but fermented wheat flour showed with a mixture of small and large oval types. The viscosity of oxidized corn starch were very lower those of cationic corn starch and unmodified corn starch. And increasing of a fermentation period of wheat flour was resulted in increasing of viscosity. The pH of commercial corn starch were 3.6-7.5 and fermented wheat flour were 3.6-5.2. Through the examination on the nature and adhesive strength of starch paste, the oxidized corn starch 60 cps which is the name of products and wheat flour which had fermented for 5 years were considered that most suitable for conservation of paper properties.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.4
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• pp.444-450
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• 2013

The purpose of this study is to evaluate chemical properties, textural characteristics and sensory properties which produces the mokwapyun from the tapioca starch. The mokwapyun-added tapioca starches hold higher moisture contents than mung bean starches. And, the ratios of tapioca starch indicate differences in the study (p<.001). The pH increases with the increasing amounts of tapioca starch and acidity measurement decreases as amount of tapioca starch increases. The 0% addition of tapioca starch is the highest for lightness and 20% addition of tapioca starch is the lowest. Both the redness and yellowness are being increased with increases in the addition of tapioca starch. According to the results of texture, 0% addition of tapioca starch is the highest for hardness, springiness and chewiness of mokwapyun which increases with additional percentages of tapioca starch. Nevertheless, it decreases the cohesiveness and brittleness due to increases in the percentage of tapioca starch. According to the result of DSC analysis, the more tapioca starch added to the mokwapyun, the higher the To, Tp, Tc temperatures become. The result of this study shows that the right contents of tapioca starch with 15% additions make positive acceptability, prepared sensory and machinery characteristics.

• Korean journal of food and cookery science
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• v.28 no.6
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• pp.871-881
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• 2012

To compare the physicochemical and gel properties of mung bean starches prepared by different purification methods, starches from Korean Eohul variety and Chinese mung bean (MB) with or without hull using alkaline solution or water as solvent were purified. The optimum conditions for making muk were investigated. Apparent amylose and total dietary fiber contents, water binding capacity, solubility and pasting properties by RVA were analyzed. The characteristics of starch gels (10% dry basis) were measured for 0 and 4 day stored at $4^{\circ}C$. The protein and ash contents were significantly different (p<0.05) and lowered in starch from dehulled MB using alkaline solution. The starches from dehulled MB using alkaline solution showed the lowest color differences. Apparent amylose contents of Eohul and Chinese starches showed 37.06-39.03% and 31.57-32.74%, respectively. Chinese starch was higher in water binding capacity but lower in solubility at $85^{\circ}C$ than others. Peak, trough, cold, and breakdown viscosities of Eohul starch were higher than those of Chinese one. Mung bean starch gel made immediately exhibited clear and glossy appearance but became whiter like milk. The crystallinities of starch and starch gel showed A and B types, respectively. The hardness, gumminess, and resilience of starch gel made immediately and hardness, cohesiveness, gumminess, and resilience of 4 day stored gels were different significantly (p<0.05). Especially, Eohul starch gels purified from hulled MB showed higher resilience (bending property) and hardness. Therefore, it was suggested that high quality muk would be made using MB starch purified from hulled Korean mung bean using water as solvent.decreased in contain more than 20% of SGP added groups. The optimal concentration of SGP was found in the range of less than 10%.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.72-72
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• 2003

A 10-week feeding trial was conducted to investigate the effects of dietary glucose, dextrin and starch on growth and body composition of juvenile starry flounder. Triplicate groups of fish (average weight, 9.7 g) were fed iso-nitrogenous (53% CP) and iso-caloric (3.8 kcal/g diet) diets containing 20% glucose, 20% dextrin and 5-25% alpha-potato starch with 5-14% lipid levels. Survival was not affected by dietary carbohydrate. Weight gain, feed efficiency and protein efficiency ratio of fish fed the diet containing 20% glucose were the lowest among all groups. The best weight gain was observed in fish fed the diets containing 20% dextrin. Growth and feed efficiency were not affected by dietary -potato starch level. Lipid contents of whole body and liver were not affected by dietary glucose, dextrin and starch at the same level. However, the lipid contents tended to decrease with increasing dietary starch level and those of fish fed the diets containing 5% alpha-potato starch were significantly higher than those receiving 10-25% alpha-potato starch. Liver glycogen content and hepatosomatic index tended to increase with increasing dietary starch level. These results indicate that juvenile starry flounder are able to efficiently utilize dextrin and -potato starch compare to glucose in diets and that alpha-potato starch could be incorporated up to 25% in the diet for optimum growth by juvenile starry flounder.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.4
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• pp.44-53
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• 2014

This research were aimed at developing starches which have high preservability and high bonding strength from corn starch, modified cationic and oxidized corn starches, as compared to the fermented wheat starch. On the lining that attaching the base paper on the back of the work with paste, the coating weight was determined by the solid contents of the paste rather than the viscosity of paste. Adhesive strength and stiffness were also determined by the solid contents of the paste. Corn starch had lower solid contents, higher viscosity, and higher adhesive strength than other starches. In the iodine stain to the surface of peeled base paper off, paste deeply penetrated into the traditional Hanji than modern Hanji. And oxidized starch paste deeply penetrated into the paper layer than the cationic starch.