• Journal of the Korean Society of Food Culture
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• v.18 no.6
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• pp.592-600
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• 2003

Male rats were fed a purified diet containing one of 3 experimental diets, gelatinized rice starch that was not modified physically (RC), gelatinized physically modified rice starch using ultrasonic homogenizer(RU), gelatinized physically modified rice starch using hydroshear homogenizer(RH) during 28 days. RC was used as the rice starch control. Feeding a physically modified rice starch (RU) caused an increase in liver weight and RH increased RNA and protein contents in kidney significantly although there were no differences in food intakes compared to feeding a RC diet. The wet weight of liver, kidney and heart were higher in RU. The wet weights of fecal output of the rats fed RH was greater than in rice control group. The gut transit time was longer in the rats fed RH than in the rice control group significantly. Serum GOT, GPT, total bilirubin concentration were tended to be lower and blood urea nitrogen was significantly lower in RH group. The maturation index of kidney was higher in RU than in RC. These results suggest that physically modified rice starch improved growth performance and physiological functions in organs of growing rats.

• Applied Biological Chemistry
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• v.50 no.3
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• pp.160-166
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• 2007

This study was performed to analyze the molecular structural and physical properties changes of modified rice starch, which particle structure was broken using high impact planetary mill and ultra fine pulverizing techniques. The average diameter and specific surface area of rice starch after pulverization decreased 20% and increased 25%, respectively. Low molecular substances content in rice starch using GPC (gel permeation chromatography) increased from 36.5% to 59.5% after pulverizing of rice starch. Damaged starch contents in rice starch also increased from 16.4% to 99.2% after pulverizing of rice starch. Water holding capacity, solubility and transmittance of rice starch after pulverization increased compared to those of control. Apparent viscosity value of rice starch after pulverization decreased to 7% in control based on $30^{\circ}C$ and 20 RPM conditions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.700-706
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• 2005

The objectives of this research were to analyze physicochemical properties of physically modified rice starch which was prepared by hydro-shear homogenizer and ultrasonic homogenizer. The 5:1 of water to starch ratio, 20,500 rpm of hydro-shear homogenizer, and 5 sec of pulse and 40 kHz of frequency of ultrasonic homogenizer, which were operated for 10 min. The 1/3 of size reduction of raw rice starch and gelatinized rice starch, and reduced of particle size were achieved by above processing conditions. The homogenization of raw rice starch and gelatinized rice starch were higher values of specific area, transmittance, solubility and swelling power than control. While, these had lower value of apparent viscosity than control. In raw rice starch, the gelatinization characteristics of ultrasonic homogenizer treated rice starch had some higher values of gelatinization temperature, peak temperature and enthalpy than those of control. While, those of hydro-shear homogenizer treated rice starch had similar values to those of control.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.428-435
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• 1994

Properties of modified rice starches prepared in drum drying and extrusion were evaluated to use for effective utilization. Blue value was the lowest (p<0.05) for waxy rice starch and L value was decreased after modification of starches. Water solubility index was the highest for modified starches prepared in extrusion, while water absorption index was the highest for modified starches prepared in drum drying. Cold-Water-Solubility was the highest (p<0.05) for modified rice starch prepared in drum drying (RD). Consistency index of RD was drastically increased as shear rate increased and yield stress was the highest for RD. Results of Gel Permeation Chromatography showed that starch components were broken down into lower molecular weight materials and amylose are degraded by modification. Changes in the X-ray diffrectometry pattern indicated the transformation of granule into an amorphous state during modification and illustrated V-type.

• Korean Journal of Food Science and Technology
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• v.44 no.5
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• pp.577-582
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• 2012

The purpose of this study was to investigate the preparation and physicochemical characteristics of n-octenylsuccinylated (OSAn) rice starches with different rice amylose contents. Amylose contents of Jinsumi flour and Milyang 261 flour were 15.42 and 20.31%, respectively. After processing by alkali treatment, amylose contents of Jinsumi rice starch and Milyang 261 rice starch were 34.21% and 39.32%, respectively. After OSAn treatment, the degree of substitution and reaction efficiency of Jinsumi starch were higher than those of Milyang 261. The stability of the modified Jinsumi emulsion was higher than that of the Milyang 261 emulsion. Viscosity of the Jinsumi emulsion was higher than that of the Milyang 261 emulsion. When the emulsions were spray dried, modified Jinsumi rice starch showed excellent coating efficiency compared to that of modified Milyang 261 rice starch. Therefore, Jinsumi was more suitable than Milyang 261 to apply for encapsulation as wall materials.

• Food Engineering Progress
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• v.15 no.4
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• pp.382-387
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• 2011

Physicohemical properties of dual-modified rice starches, cross-linked (with $POCl_{3}$) and hydroxypropylated (with propylene oxide) rice starches, were studied. Rice starch was cross-linked using $POCl_{3}$ (0.005%, 0.02% (v/w)) at 45$^{\circ}C$ for 2 hr and then hydroxypropylated using propylene oxide (2%, 6%, 12% (v/w)) at 45$^{\circ}C$ for 24 hr, respectively. Swelling power, solubility, thermal properties (DSC) and pasting properties (RVA) of cross-linked and hydroxypropylated (CLHP) rice starches were determined. Swelling power of CLHP rice starch increased at relatively lower temperature than native rice starch. Solubility of CLHP rice starch was lower than that of native rice starch. Peak viscosity of CLHP rice starch was lower than that of native starch while holding strength and final viscosity were increased with modification. Breakdown value was lower and setback value was higher than native rice starch. DSC thermal transitions of CLHP rice starch shifted toward lower temperature. Amylopectin-melting enthalpy of CLHP rice starch decreased, whereas it was not affected by the amount of $POCl_{3}$.

• Food Engineering Progress
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• v.15 no.4
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• pp.332-337
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• 2011

Physicochemical properties of hydroxypropylated and cross-linked (HPCL) rice starch were investigated. Dual modification of rice starch was carried out by hydroxypropylation using propylene oxide (2, 6, and 12%) and then crosslinking using phosphorus oxychloride (0.005% and 0.02%). Swelling power of dual-modified rice starch increased at lower temperature (60$^{\circ}C$) than that of native rice starch (70$^{\circ}C$). HPCL rice starch showed slightly lower solubility (1.6-6.1%) than native rice starch (2.2-13.8%). Solubility and swelling power tended to gradually increase with increasing phosphorus oxychloride contents. RVA pasting temperature (66.2-70.8$^{\circ}C$) and peak viscosity (160.6- 171.1 RVU) of HPCL rice starch were lower than that of those of native starch (71.3$^{\circ}C$, 190.4 RVU) and decreased with increasing propylene oxide concentration. DSC thermal transitions of HPCL rice starches shifted to lower temperature and show less amylopectin melting enthalpy (11.8-9.8 J/g) than that of native rice starch (11.9 J/g). Overall, physicohemical properties of HPCL rice starches were highly dependent on hydroxypropylation rather than crosslinking.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1264-1269
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• 2014

This study investigated the effects of rice starch addition, including native, acetylated, and hydroxypropy-lated rice starch, on the quality characteristics of instant fried noodles. Compared to 100% wheat flour (control), flours containing acetylated or hydroxypropylated rice starch showed reduced initial pasting temperatures as well as peak and breakdown viscosities as determined using a Rapid Visco-Analyzer (RVA). The addition of acetylated and hydroxylated rice starch as well as native rice starch increased cooked weight, volume, and water absorption of the fried noodles compared to control noodles. The addition of native rice starch tended to increase softness of noodles, whereas addition of acetylated or hydroxypropylated rice starch significantly lowered hardness, gumminess, and chewiness values. The results of the sensory evaluation indicate that noodles containing rice starch showed improved sensory characteristics such as color, appearance, flavor, taste, and texture. Especially, acetylated rice starch could be used to improve eating quality of instant fried noodles.

• The Korean Journal of Food And Nutrition
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• v.23 no.1
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• pp.88-93
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• 2010

The principal objective of this study was to evaluate the physicochemical characteristics of brown rice Dasik prepared with different 5 levels(0, 25, 50, 75, 100%) of modified potato starch powder. We assessed the general compositions, Hunter's color values, the mechanical characteristics, and conducted a sensory evaluation analysis of brown rice Dasik at room temperature($20^{\circ}C$). The more modified potato starch powder composition was increased, the content of ash, protein and fat were significantly decreased(p<0.05). We noted that the luminance of samples were increased the more modified potato starch powder composition was increased, but in Hunter's a and b values were decreased. With regard to the mechanical properties of the Dasik samples, we noted significant differences in hardness, gumminess, chewiness but no differences in springiness, cohesiveness and adhesiveness were detected. The more modified potato starch powder composition was increased, the more the score of hardness, gumminess and chewiness were higher. The results of sensory evaluation showed that there were significant differences on the color, sweetness, mouth-feel, chewiness, overall quality of the Dasik samples(p<0.05). The score of brown rice Dasik with 50%(w/w) modified potato starch(BM2) in color, mouth-feel, chewiness, overall quality were significantly increased than those of other samples.

• Korean Journal of Food Science and Technology
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• v.40 no.3
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• pp.290-296
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• 2008

This study examined the physicochemical properties of chemically and enzymatically cross-modified waxy rice starches. The waxy rice starch was cross-linked using phosphorous oxychloride, and then partially hydrolyzed with four commercial ${\alpha}$-amylases (Fungamyl, Termamyl, Liquozyme, Kleistase). Swelling power and the moisture sorption isotherm did not change with cross-modification. Two cross-modified waxy rice starches (hydrolyzed with Termamyl and Liquozyme) showed higher solubilities than native starch and the two other cross-modified starches (hydrolyzed with Fungamyl and Kleistase). In terms of RVA characteristics, the two cross-modified waxy rice starches hydrolyzed with Termamyl and Liquozyme, respectively, had lower peak viscosity, holding strength, and final viscosity than the native starch. However, the two starches hydrolyzed with Fungamyl and Kleistase, respectively, revealed higher peak viscosity, holding strength, and final viscosity than the native starch. No differences were displayed in the X-ray diffraction patterns and DSC thermal characteristics of the cross-modified waxy rice starch as compared to both the native and cross-linked starches, indicating that cross-linking and enzymatic hydrolysis occurred in the amorphous region and did not alter the crystalline region.