• Journal of Korea Technical Association of The Pulp and Paper Industry
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• 제35권3호
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• pp.21-28
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• 2003

It is essential to use base papers having proper surface characteristics in coating operation for improving coated paper quality and coater runnability. To fulfill these purposes surface sizing of coating base stock with anionic oxidized starch is commonly practiced. It is suggested that use of cationic starch for surface sizing rather than conventional oxidized starch will improve coated paper quality since cationic starch penetrates less into paper structure because of its strong electrostatic interaction with anionically charged paper surface. Strong interaction of cationic surface sizing starch with anionic coating color is expected to promote rapid immobilization of the coating color and improve coating holdout and optical property. The immediate objective of this study was to examine the influence of surface sizing starches on the properties of coated papers. Structural characteristics of the coatings formed on the substrate surface sized with cationic and anionic starches were examined. To enhance the efficiency of cationic surface sizing starch on coated paper properties, strongly charged cationic polymers were added to the surface sizing starch and its effect on coated paper properties was evaluated. Results showed that opacity and light scattering coefficient of coated paper were higher when base paper surface sized with cationic starch was used. Addition of less than 1% of cationic poly-DADMAC to the cationic surface sizing starch improved the opacity of coated paper significantly.

• Journal of the Korean Society of Food Science and Nutrition
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• 제28권1호
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• pp.132-139
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• 1999

Physicochemical properties of the crosslinked potato starches of MDC(Molar Degree of Crosslinking) 0.137~3.333 treated with epichlorohydrin were examined. MDC increased proportionally as epichlorohydrin concentration increased. Water binding capacity increased but blue value decreased with increasing MDC. Gelatinization trends obtained from DSC thermograms and transmittance showed that the gelatinization temperature of the crosslinked potato starch was higher than that of native potato starch, but there was no significant difference among the crosslinked potato starches. Solubility and swelling power decreased with increasing MDC. X ray diffraction patterns and scanning electron micrographs showed that the crosslinking of starch did not affect the crystallinity and the granule shape of starch.

• Food Science and Biotechnology
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• 제16권5호
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• pp.663-674
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• 2007

Starches from different botanical sources differ in the ratio of amylose to amylopectin contents, molecular structures of amylose and amylopectin, granule morphology, and minor-component contents. These structural features result in different gelatinization, pasting, retrogradation properties, and enzyme digestibility of starch granules. In this review, compositions and molecular structures of starches and their effects on the physicochemical properties are summarized and discussed.

• Food Science and Biotechnology
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• 제18권4호
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• pp.991-995
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• 2009

As a principle ingredient in omija-eui, the physicochemical properties of mung bean starch (MBS) paste were investigated and compared to those of rice and corn starch. The amylose and the protein content of MBS were higher than those of rice or corn starch while the total sugar content and the swelling power of MBS were lower. In addition, the clarity of MBS paste was higher than either rice or corn starch paste. Regarding pasting properties, the peak viscosity and cool paste viscosity of MBS were higher than those of either rice or corn starch. During the freeze-thaw cycle, MBS exhibited higher degree of syneresis than corn and rice starch, which decreased with high starch concentration and heating temperature. The paste properties and freeze-thaw stability of MBS showed a potential for improving the quality of omija-eui.

• Korean Journal of Food Science and Technology
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• 제16권2호
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• pp.175-178
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• 1984

The effects of the addition of starch, salt and soda ash to the dough for Naengmyon (wheat-sweet potato starch) on the mechanical property of Naengmyon noodle were evaluated by using creep test. The strain measurement was made by taking photograph with VTR system. The creep curve of noodle strand could be fitted to the 4 element Burgers model. The instantaneous elasticity and Newtonian viscosity of the noodle strand decreased by the addition of starch. The instantaneous elasticity decreased by the addition of salt up to 4%. The mechamical parameters of the noodle varied inconsistently by the addition of soda ash.

• Journal of the Korean Society of Food Culture
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• 제22권2호
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• pp.254-260
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• 2007

This study was examined closely physiological activation and intended to present the possibility of developing food low-fat food. Developing carbohydrate fat replacer as materials for low-fat food made of Korean potato starch, it is expected that the new demand of fat replacer will be created. Potato starch was modified by chemical modification. The calorie of starch of GPS was measured to be 3.0 kcal/g, 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 gel of starch and modified starch in constant rate through utilization of modified starch. When producing mayonnaise by substituting edible oil with gel of modified starch in 10-50%, calorie was reduced by 44${\sim}$45% when substituted by 50%, suggesting the potential of low-fat food. Measuring viscosity of mayonnaise by Brookfield viscometer, the mayonnaise with HPR showed high viscosity and the chemical modified starch group of EZ also showed high viscosity. Generally, the material property of mayonnaise tended to reduce in all measured items when oil and fat are substituted by starch substituting materials and the substituting materials increase. When it comes to the emulsification stability of mayonnaise with starch substituting materials, emulsification stability of all mayonnaise with starch substituting materials is lower than that of compared group. While the group with NL as commercial fat replacer showed emulsification stability which was slightly higher than group with modified starch and the substitution group of HPR showed higher emulsification stability. Sensory evaluation for low-fat mayonnaise by substituting oil the products substituted by modified starch was more preferred than general starch substituting products such as GPS. While NL as commercially fat replacer showed the hight preference, products with H40, EZ were also highly preferred.

• Korean Journal of Food Science and Technology
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• 제24권1호
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• pp.54-58
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• 1992

The reological properties of commercial corn starch solutions at various concentrations($4{\sim}9%$) and temperatures($30{\sim}60^{\circ}C$) were investigated. The rheological behavior of corn starch solutions was illustrated by Herschel-Bulkley equation and exhibited pseudoplastic behavior with yield stress. The degree of pseudoplasticity of starch solution increased as the starch concentration increased but was independent on temperature. Apparent viscosity and yield stress of starch solutions were exponentially dependent on concentration and temperature. The critical concentrations for sol-gel transition and for the onset of close-packing of the starch granules were $6.22{\sim}6.52%\;and\;2.68{\sim}2.78%$ respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제16권3호
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• pp.247-254
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• 1983

In previous paper (Lee and Kim, 1983) the effect of moisture level and frequency on dielectric properties of sardine starch paste was mentioned. The effect of temperature and starch content of the paste upon dielectric permittivity and activation energy was discussed in this report. Addition of starch affected on dielectric property. Increases of starch in the mixtures resulted in higher complex permittivity and lower critical moisture content (hc) as shown in the mixtures with $20\%$ and $50\%$ starch which were ${\varepsilon}^{\ast}=2.97+j0.36,\;hc=8.0\%;\;{\varepsilon}^{\ast}=3.54+j0.44,\;hc=7.8\%$, respectively while being ${\varepsilon}^{\ast}=2.73+j0.29,\;hc=8.4\%$ for the plain ground sardine meat. When temperature was raised the complex permittivity tended to increase at above the critical moisture content in all cases. The activation energies for plain ground meat and $30\%$ starch added mixture at below the critical moisture of $8.4\%$ were 15.44 kcal/mol and 13.86 kcal/mol while those at the moisture of $12.2\%$ were 10.27 kcal/mol and 9.31 kcal/mol, respectively.

• Korean journal of food and cookery science
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• 제31권6호
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• pp.696-702
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• 2015

Rice dumpling shells were prepared with different levels of hydrocolloids, such as hydroxypropyl methyl cellulose (HPMC), and potato starch. After steaming, the physical, sensory, and cooking properties of the shells were measured. Increasing the amount of potato starch decreased the pasting temperature and increased the peak viscosity. With the addition of hydrocolloids, water absorption and cooking loss for the rice dumpling shells decreased significantly. For the textural properties, the rice dumpling shells with hydrocolloids showed lower hardness and higher springiness than the control, and especially, 10% potato starch and 3% HPMC addition (P10H3) improved the texture of the rice dumpling shells the most. The sensory results seemed to be affected more by the addition of potato starch than HPMC, and over 15% addition of potato starch significantly decreased the quality of the rice dumpling shells. By addition of adequate amount of hydrocolloids (3% HPMC and 10% potato starch), the sensory quality of rice dumpling shells can be effectively improved.

• Food Engineering Progress
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• 제21권4호
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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.