• Korean Journal of Food Science and Technology
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• v.25 no.3
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• pp.264-269
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• 1993

Molecular structural properties of legume starches were investigated. In intrinsic viscosity and degree of Polymerization of amylose and amylopectins, cow pea and mung bean were high, but kidney bean was low. Low molecular weight fractions for kidney bean starch were much eluted by gel chromatography. In the elution profiles of their amylose by Sepharose 2B-CL, molecular weight of kidney bean amylose was smaller than that of other amylose Molecular weights of cow pea and mung bean amyloses were large, but that of kidney bean amylose was small and red bean amylose was medium. The elution profiles by Sephadex G-50 after debranching amylopectins with pullulanase showed similar patterns.

• Applied Biological Chemistry
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• v.33 no.2
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• pp.105-108
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• 1990

The numbers of aleurone layers and thickness of pericarp of waxy rice in dorsal side were higher than those in vental side, However, varietal characteristics of the bran structures were observed. The water uptake rates of brown rice at $60^{\circ}C$ were similar between $j{\times}indica$ varieties(Hangangchalbyeo, H and Baegunchalbyeo, B) and higer than that of japonica variety (Shinsunchalbyeo, S). Inherent viscosities for H, B and S waxy rice starches were 1.92, 1.84 and 1.73 $dlg^{-1}$, respectively. The minimum moistures for gelatinization of waxy rice starches determined by DSC were $36.4{\sim}38.6%$ which represented 4moles of water per mole of hexose unit.

• Food Science and Biotechnology
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• v.16 no.4
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• pp.646-649
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• 2007

The effect of the addition of 2 kinds of chemically modified starches (the anti-caking agents; tapioca starch and com starch) on caking of ramen soup was observed using a low-resolution proton-pulsed nuclear magnetic resonance (NMR) technique. After storing ramen soup samples with diverse compositions of modified starch at 20-40% relative humidity for 4 weeks, changes in the spin-spin relaxation time constant ($T_2$) were measured as a function of temperature. $T_2-Temperature$ curves for ramen soup containing modified starches showed that the caking initiation temperature (glass transition temperature) was increased by $5^{\circ}C$ following the addition of only 0.5% modified cornstarch. The results indicate that the modified com starch used in this study would be an effective anti-caking agent for ramen soup, thus prolonging the shelf life of the product.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.6
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• pp.738-747
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• 1992

The important legumes in Korea are mungbean, red bean, kidney bean and cowpea. Mungbean has traditionally been used for mook (jelly-like starch gel) preparation. Cowpea has recently been utillized for substitution of mungbean. The major use of sediment of red bean is for the sweet paste. The studies related to legume starches and flours (air-dried sediment) in Korea are concentrated on the understanding of the properties of mook. The structure of starch, gelatinization and gelling properties of legume starches and flours are reviewed with emphasis of Korean literatures.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.189-195
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• 2002

Corn starch was modified by oxidation with sodium hypochlorite (NaOCl) as an attempt to expand the application of starches in food industry. Corn starch was oxidized with 0.25, 0.5, 0.75, 1.0 and 1.5% active Cl/g starch at pH 7.0 and $25^{\circ}C$ for 10 minutes. The size, shape and amylose content of oxidized starches were similar to those of native corn starch. As the extent of oxidation increased, solubility, swelling power and the amount of soluble amylose increased, X-ray diffraction patterns changed, and relative crystallinity decreased. In Brabender amylogram, oxidation did not chance the gelatinization temperature, but oxidized starches had a lower peak in viscosity and their cooled pastes gave less setback, compared with native corn starch.

• Korean Journal of Food Science and Technology
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• v.19 no.5
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• pp.435-440
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• 1987

Gelatinization properties of heat-mositure treated potato and sweet potato starches were investigated. Water-binding capacity of starch was increased by heat-mositure treatment, which was more pronounced in sweet potato starch. Blue value was not affected by the treatment. Amylograph viscosities were decreased by heat-mositure treatment, which was more pronounced in potato starch. Critical concentration of NaOH for gelatinization of starch increased as moisture level increased. Gel volume of starch upon KSCN gelatinization was higher in potato starch. Gelatinized starches showed Binghamapseudoplastic behavior. Consistency index and yield stress were drastically decreased upon heat-moisture treatment.

• The Korean Journal of Food And Nutrition
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• v.32 no.4
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• pp.304-311
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• 2019

Ohmic heating is a heating method based on the principle when an electrical current passes through food. Since this method is internal, electrical current damage occurred during heating treatment. The results of ohmic heated starch's external structure, X-ray diffraction, DSC analysis and RVA were differed from those of conventional heating at the same temperature. Several starches changed more rigid by structure re-aggregation. This change in starch was caused by change of physical, chemical, rheological property. The rheology of ohmic heated potato and corn starch of different heated methods were compared with chemically modified starch. After gelatinization, sample starch suspension (2%, 3%) measured flow curves by rheometer. Cross-linked chemically modified starch's shear stress was decreased with degree of substitution reversibly. Ohmic heated more dramatic, at $60^{\circ}C$. Potato starch's shear stress was less than commercial high cross-linked modified starch. Flow curves of potato starches measured at $4^{\circ}C$, $10^{\circ}C$, $20^{\circ}C$. Showed that Ohmic heated potato starch's shear stress ranging between $4^{\circ}C$ and $20^{\circ}C$ was narrower than modified starch. According to this study, ohmic heated potato starch can be used by decreasing viscosity agent like cross-linked modified starch.

• Korean Journal of Food Science and Technology
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• v.36 no.4
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• pp.547-552
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• 2004

Attempt was made to establish identification methods for irradiated starch. Commercial starches (corn starch/CS, sweet potato starch/SS, and potato starch/PS) were irradiated at 0-6.0 kGy and used to measure viscosity with Brookfield DV-III programmable rheometer. Starch suspensions were prepared at 8.0 (7.2%, d.b.), 8.5 (7.3%, d.b.), and 9.0% (7.3%, d.b.) for CS, SS, and PS, respectively at 100 rpm in spindle speed. Results showed viscosities of samples significantly decreased (p<0.05) as irradiation dose increased, with $R^2$ 0.9754, 0.9618, and 0.9888 for CS, SS, and PS, respectively. Irradiation dose at 1.5 kGy induced decrease in viscosity as compared to non-irradiated control by 34, 57, and 51% in CS, SS, and PS, respectively, suggesting viscometry could lie applied to identify irradiated starches. Solubility and alkali number of irradiated starches significantly increased with irradiation doses, while swelling power decreased (p<0.05). Results suggested solubility, alkali number, and swelling power for irradiated starches complement identification results of viscometry.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.385-391
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• 2006

Physicochemical properties of hydroxypropylated waxy rice starches were investigated to reduce steeping-time of yukwa (Korean oil-puffed rice snack) processing. Swelling power of hydroxypropylated waxy rice starch increased at relatively higher temperature $(60^{\circ}C)$ than native waxy rice starch $(70^{\circ}C)$. Solubility of hydroxypropylated waxy rice starches increased with increasing propylene oxide content. Pasting temperature $(66.3-66.9^{\circ}C)$ and peak viscosity (216-232 RVU) of hydroxypropylated waxy rice starch were higher than those of native starch (179 RVU) and increased with increasing propylene oxide content. DSC thermal transitions of hydroxypropylated waxy rice starches shifted toward higher temperature. Amylopectin melting enthalpy of hydroxypropylated waxy rice starch (8.4-9.2 J/g) was similar to native starch (9.0 J/g). X-ray diffraction patterns of native and hydroxypropylated waxy rice starches showed typical A-type pattern with no significant differences between them, suggesting hydroxypropylation only affected amorphous region. Results suggest hydroxypropylated waxy rice starch is not applicable for yukwa due to low puffing efficiency and dark color.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.6
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• pp.591-596
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• 2000

The effect of starches such as potato, corn and wheat starch on the rheological properties of ocean jumbo squid kamaboko was investigated. Changes in the water holding capacity and color values of those kamaboko gels was also studied using the maximum gel strength endowing starch, Wheat starch could ive the better water holding capacity and breaking stress than potato or corn starch within $10{\%}$ additional level but corn starch resulted the highest those value at $20{\%}$ added. Wheat starch had higher level of breaking strain and jelly strength at $10{\%}$ then in descending order were corn starch, potato starch. But those starches were decreased after $15{\%}$ level. Texture map showed the simple rheological properties of each starches heat gel with jumbo squid kamaboko, Corn starch map showed more tough and brittle than the other. Potato starch map showed more elastic gel than corn starch. Wheat starch map could make elastic-mushy gel. There was no significant color differences of each starches but the whiteness of each starch showed increase when the starch rate was increased.