• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.2
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• pp.244-250
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• 1994

Starch phosphates were prepared by dry heating method using sodium triphosphate as a substitution reagent and their physicochemical properties were investigated with the chucheongbyeo and samkangbyeo. The solubility and swelling power of rice starches were increased by phosphorylation reaction. The solubility of the chucheongbyeo was greater than that of samkangbyeo , but the swelling power was appeared in vice versa. The transparency of raw starch was increased at the 6$0^{\circ}C$, but phosphorylated rice starch was begun to increase from 5$0^{\circ}C$. Light transmittance was higher inthe phosphorylate drice starch. The lightness of phosphyorylated rice starch decreased more than that of raw starch. Whereas the yellowness of phosphorylated rice starch increased. The temperature of initial gelatinization of the phosphorylated chucheong and samkang rice starch was shown to 5$0^{\circ}C$ and 53$^{\circ}C$, respectively. lowering 14-15$^{\circ}C$ in temperatureby the phosphorylation . The viscosity as well as by the phosphorylation reaction was raised 7.4-8.4 times, respectively. The hardness, adhesiveness, cohesiveness and texture which is rheological properties of starch gel increased by the phosphoryulation reaction. The chucheong rice starch gel was slightly higher in its rheolgocial values thanthat of the samkang rice starch gel. The rice starch particles were shown to polygonal structure, but they were deformed in the phosphorylated starch.

• The Korean Journal of Food And Nutrition
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• v.28 no.4
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• pp.586-593
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• 2015

The baking properties of gluten-free rice bread with different percentages of corn starch and waxy corn starch were investigated. The specific gravity and color (L, a, b) of the dough as well as the appearance, color (L, a, b) and texture of the rice bread were analyzed. Replacement of rice flour with 1, 2.5, 5, 7.5 and 10% corn starch did not have a significant effect on the specific gravity and color of the dough. The volume and specific volume of the rice bread showed an increasing trend as the amount of added corn starch increased. The chewiness, gumminess and hardness of the rice bread showed a decreasing trend as the amount of added corn starch increased. Replacement of rice flour with 1, 5 and 10% waxy corn starch did not have a significant effect on the specific gravity and color of the dough. The color of the rice bread showed an increasing trend as the amount of added waxy corn starch increased. These results suggest that replacement of rice flour with 7.5% corn starch or 1% waxy corn starch is effective for gluten-free rice bread.

• Korean Journal of Human Ecology
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• v.14 no.6
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• pp.1037-1046
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• 2005

Using three consecutive years' harvested rices and their starches isolated from rice flours by alkaline method, it was found that no significant aging effect on rice flour and starch was observed based on following results. Proximate data of flours or starches showed in similarity, except high level of crude fat in rice flour and rice starch harvested in 2002. In SEM, the surface of aged rice flour had slightly layered shape due to possible abrasion during storage, and that of aged starch showed more smooth and less rigid polygonal shape. X-ray diffraction patterns of flours and starches were all A type, and crystallinity of rice starch harvested in 2000 had the smallest. From tristimulus colorimetry (Hunterlab Color), total color difference ($\Delta$E) calculated from L, a, and b gave less color difference with the darkest in 2002 harvested one among flours and the lightest in 2001 one among starches. WBCs of both 2002 rice flour and starch were the lowest among samples studied. At 80$^{\circ}C$, swelling power and solubility of rice starches harvested in 2000, 2001 and 2002 were 14.35, 9.75; 14.04, 9.6; and 12.49, 8.82, respectively. The highest peak viscosities measured by RVA were shown both in 2001 rice flour and in its starch. Starch and milled rice flour harvested in 2000 had higher hydrolytic $\alpha$-amylase, compared to other flour and starch samples.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.757-761
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• 1995

The relationship between the molecular structure of rice starch and the texture of cooked rice was investigated using hot-water soluble rice starch. The structure of hot-water soluble starch bound amylose which was composed of small molecular weight and amylopectin which was composed of chain length of $\overline{DP}\;10{\sim}20$, and the average composition of amylose : amylopectin was 7 : 3. The molecular weight of amylose was the smaller and super long chain of amylopectin was the fewer, the extractable ratio of hot-water soluble rice starch was the higher. And hot-water solubility of rice starch be responsible for molecular structure of starch. On the texture of cooked rice, the extractable ratio of hot-water soluble rice starch was the higher, the hardness was the lower and the adhesiveness was the higher. The results suggest that the molecular structure of rice starch could be responsible for the texture of cooked rice.

• 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.

• Korean journal of food and cookery science
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• v.24 no.3
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• pp.273-281
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• 2008

To determine the nutritional quality and physical properties of ginseng-chicken meat porridge, 10 kinds of ginsengchicken meat porridge samples containing waxy and/or non-waxy rice were analyzed for in vitro protein digestibility and their degree of starch hydrolysis. Viscosity and spreadness were determined for the gelatinized pastes of the porridge samples. Microphotographs of the starch granules and pastes were studied to confirm structural changes in the rice starch during cooking. The starch paste from non-waxy rice porridge had higher viscosity than the starch paste from the waxy rice porridge; however, in the case of the ginseng-chicken meat porridge, the difference in viscosity was negligible. Microphotograph comparisions between the waxy rice porridge and non-waxy rice porridge indicated apparent differences in the shapes of their starch granules and gels. The granule surface of the non-waxy rice was very rough while that of the waxy rice was very smooth; this difference would lead to organoleptical discrepancy. The added ginseng increased the protein digestibility of the chicken meat; however, the protein digestibility of the ginseng-chicken meat porridge was lower than that of the chicken meat or rice porridge due to inhibited protein digestion by the gelatinized starch. Finally, the rice porridge had increased starch hydrolysis with additions of chicken meat and vegetables.

• 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.

• 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 Culture
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• v.22 no.5
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• pp.645-651
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• 2007

Male weanling Sprague Dawley rats were used to evaluate the effect of dietary rice starch with different particle size on growth performance, intestinal function and proliferation. There were two dietary treatment: rice starch (RS), ultra finely pulverized rice starch with less than $15{\mu}m$ size (PRS). They were eight rats per treatment. In vitro digestibility, body weight change and organs weight were evaluated. Serum GPT, GOT and blood urea nitrogen were analyzed. Transit time, short chain fatty acid contents of cecum, and cell proliferation of duodenum and jejunum were measured. In vitro digestibility of PRS was higher than that of RS. Rats fed ultra finely pulverized rice starch for 3 weeks grew faster than rats fed rice starch. PRS group has higher weights of liver, kidney, spleen and epididymal fat pad, perhaps as a result of increased digestibility. GPT and GOT were not different between two groups. Blood urea nitrogen was higher in RS-fed rats than that of PRS-fed rats. Feeding ultra finely pulverized rice starch resulted in a proliferation of duodenum significantly. These results suggest that ultra finely pulverized rice starch increases the growth performance in weanling animals with reduced number of cells in the cell cycle of small intestine.

• Applied Biological Chemistry
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• v.34 no.1
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• pp.75-76
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• 1991

Bran structure and gelatinization property of upland and lowland japonica waxy brown rice were compared. Dimension, weight and number of aleurone layer were similar between upland(Nonglimna 1) and lowland(Shinsunchalbyeo) rices, but the aleurone layer and pericarp of upland rice were thicker. Water uptake rate of upland rice at $60^{\circ}C$ was lower than that of lowland one. There was no difference in intrinsic viscosity between two rice starches. Upland rice starch had lower onset temperature, narrower gelatinization temperature and lower water content lot gelatinization compared with lowland rice starch.