• Journal of Nutrition and Health
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• v.29 no.2
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• pp.199-205
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• 1996

The effects of several carbohydrate sources on plasma, liver and fecal lipid contents of rats fed diet containing sucrose, corn starch, brown rice, milled rice or wheat flour with 0.3% cholesterol for four weeks were investigated. Plasma triglyceride and total cholestrol increased significntly in sucrose group, and decreased significantly in milled rice group compared to other three groups. There were no significant differences in plasma lipid contents among corn starch, brown rice and wheat flour groups. The contents of liver triglyceride and cholesterol in brown rice group decreased significantly compared to there four groups. Fecal excretion of total cholesterol in rice and wheat flour groups was significantly higher than in sucrose and corn starch groups. The contents of fecal bile acid increased significantly in milled rice and brown rice groups compared to other three groups. Fecal bile acid content of wheat flour group was similar to those of sucrose and corn starch group. From these results, it is suggested that rice has a possibility of hypolipidemic effect in cholesterol fed rat.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.44-49
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• 2005

Physicochemical properties of hydroxypropylated rice starches were investigated. Swelling power of hydroxypropylated rice starch increased at relatively lower temperature than native rice starch. Solubility of hydroxypropylated rice starch was lower (1.9-13.4%) than that of native rice starch (2.2-13.8%), and increased with increasing amount of propylene oxide. Pasting temperature ($66.2-70.8^{\circ}C$) and peak viscosity (2,843-3,395cp) of hydroxypropylated rice starch were lower than those of native starch ($71.6^{\circ}C,\;3,976\;cp$) and decreased with increasing amount of propylene oxide, regardless of reaction time. DSC thermal transitions of hydroxypropylated rice starches shifted toward lower temperature. Amylopectin-melting enthalpy of hydroxypropylated rice starch decreased (11.8-9.8J/g) with increasing amount of propylene oxide and was lower than that of native starch (11.9 J/g). These results indicate hydroxypropylation lowered swelling power and gelatinization temperatures of rice starch, because internal bonds of rice starch molecules were sterically weaken by substituted hydroxypropyl groups.

• Korean Journal of Human Ecology
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• v.19 no.1
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• pp.191-201
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• 2010

This study attempted to examine the application of retrograded starch (RS3) isolated from rice flour into Madeleine which is easy to make, supply enough energy and micro nutrients with adequate drinks, and prevent an adult disease. This could be a popular food to anyone regardless of age and gender who avoid rice and become high value-added, processed rice foods. For this, control Madeleine was made from wheat flour and an experimental one was made from 5 or 10% rice RS3 addition as well as wheat flour. Four different types of rice were produced from Premium Ho-Pyong Rice, that is, dry milled rice flour(RFD), soaked for 8 hours and milled, followed by air-dried rice flour(RFW), rice starch(RST), and retrograded rice starch or enzyme-resistant starch(RS3). The results found were as follows: Proximate compositions were decreased with soaking to make RFW, RST and RS3, compared to RFD. RS3 had the highest L, +a and ${\Delta}E$ with the lowest +b, changing it to a dark color, explaining the need for heat control during processing. At $80^{\circ}C$, the swelling power was shown in the order of RST>RFW>RFD>RS3 and the solubility of RS3 was the highest. There were significant differences in viscosities of peak, trough, cold, breakdown and total setback of all rice samples using RVA (p<0.001). Due to the pH of RS3, the Madeleine batter became acidic (p<.01) and expanded, resulting in more air cells and open texture. With an increasing RS3 level in Madeleine, several textural attributes among 'fresh' and 'stored at room temperature' Madeleine samples were significantly different by using Texture Analyzer. While the addition of RS3 in Madeleine did not significantly affect the sensory evaluation, indicating RS3 isolated from rice as a beneficial ingredient for processed rice products.

• Korean Journal of Food Science and Technology
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• v.47 no.6
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• pp.793-796
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• 2015

The in-vitro starch digestibility of white and brown rice flours was continuously characterized from a rheological point of view. Specifically, the in-vitro viscosities of the rice digesta samples were monitored under simulated oral, gastric, and intestinal conditions. A trend of decreasing viscosities in all the digesta samples was observed during the in-vitro digestion. After cooking, the brown rice sample exhibited lower viscosity than that of the white rice flour due to the presence of more non-starch components. A similar tendency was observed during the simulated oral and gastric digestions. However, the viscosity crossover between the white and brown rice samples was observed during intestinal digestion. In addition, the amount of glucose released from the brown rice flour was significantly lower than that from the white rice flour. Thus, the slower rate of starch hydrolysis in the brown rice flour could be related to its in-vitro rheological behaviors.

• Preventive Nutrition and Food Science
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• v.16 no.2
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• pp.157-164
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• 2011

The influence of sodium salts and chlorides at various concentrations (0.05, 0.10, 0.50, and 1.00%) on the reheating behavior of retrograded rice starch and cooked rice was investigated. The degree of gelatinization of the all retrograded rice starch gels and the cooked rice containing sodium salts and chlorides increased after reheating compared to the starches without salt. Gelatinization also showed an increasing trend as the concentration of sodium salts and chlorides increased. The increase of gelatinization after reheating the samples containing sodium salts and chlorides was greater than 38.0%. The reheated retrograded rice starch and cooked rice containing $Na_3PO_4$ showed the lowest set back value and retrogradation rate constant. Among all the samples, the cooked sample containing $Na_3PO_4$ showed the highest increment of gelatinization after reheating. Also, this same sample showed the lowest retrogradation degree.

• Korean journal of food and cookery science
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• v.8 no.3
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• pp.291-296
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• 1992

The physicochernical properties of Korean buckwheat starches were investigated. The results were as follows; 1. Water binding capacity of kangwon hull buckwheat starch was 106.55% and that of Kangwon rice buckwheat was 99.35%. 2. The pattern of change in swelling power of hull buckwheat starch for increasing temperature started to increase at 60$^{\circ}C$ and increased rapidly from 80$^{\circ}C$, and that of rice buckwheat increased slowly from 60$^{\circ}C$ to 90$^{\circ}C$. 3. The ranges of gelatinization temp. of hull buckwheat and rice buckwheat starches were 70~75$^{\circ}C$ and 75~85$^{\circ}C$, respectively. 4. The blue value of hull buckwheat starch and rice buckwheat starch were 6.25 and 0.62, respectively. 5. The alkali number of hull buckwheat starch and rice buckwheat starch were 1.28 and 3.68 respectively. 6. The amylose content of hull buckwheat and rice buckwheat starch were 32.26% and 38.09%. 7. Periodate oxidation of hull buckwheat starch resulted that amylose had me average molecular weight of 103, 004, degree of polymerizatlon of 572 and amylopectin had me degree of branching of 7.64, glucose unit per segment of 13.09, and periodate oxidation of rice buck wheat starch resulted mat amylose had me average molecular weight of 125, 654, degree of polymerization of 698 and amylopectin had degree of branching of 6.59, glucose unit per segment of 15.16.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.289-297
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• 2006

In this study we examined the changes in weight and dimension, protein and amylose contents, and pasting properties of brown rice flour, as well as the gelatinization properties of starch, from two non-waxy japonica cultivars and one waxy japonica cultivar planted in an experimental field in 2002 under the same fertilizer conditions. The weight of both rough and brown rice increased consistently up to 42 days after flowering (DAF) for the non-waxy rice and to 35 DAF for the waxy rice. The changes in dimension of the brown rice kernel indicated that the length was maximized first, followed by breadth and then thickness. The protein content of the non-waxy rice remained fairly constant, but that of the waxy rice decreased by about 1% after 14 DAF. The amylose content of the non-waxy brown rice flour increased, but that of the waxy brown rice flour decreased during kernel development. As the kernel developed, the peak viscosity of the non-waxy rice flour increased up to 35 DAF, after which it decreased, whereas that of the waxy brown rice flour increased consistently. The gelatinization temperature of starch also increased in the waxy rice during kernel development up to 21 DAF. The gelatinization enthalpy of starch, however, increased in all rice cultivars throughout the kernel development.

• 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.

• Korean journal of food and cookery science
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• v.23 no.3 s.99
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• pp.314-320
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• 2007

The objective of this study was to investigate the effect of grain size on the physicochemical properties of rice porridge. Here, the grain size of the rice was classified as whole grain, half grain, and flour by traditional Korean cooking methods. The viscosity of the rice flour porridge was highest for the among the three different grain size porridges. In the amylographs, the increase in viscosity for the whole grain porridge was higher than that of the rice flour porridge during cooling. The soluble solid and reducing sugar contents of the rice porridges increased according to the rice grain size, while the blue value decreased. The SDI (starch digestion index) increased according to the rice grain size. The RDS (rapidly digestible starch) was highest while the SDS (slowly digestible starch) the lowest in the rice flour porridge. The morphologies of the rice porridges were examined by SEM and showed a smoother surface and more exudated gelatinized granules in the rice flour than in the whole grain rice porridge. In conclusion, rice porridges made from the smallest possible grain size such as flour may be helpful for people with weaker digestive systems such as infants, the elderly, and hospital patients.

• Journal of Dairy Science and Biotechnology
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• v.26 no.2
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• pp.45-49
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• 2008

We studied the feasibility of monitoring and controlling the manufacturing process of an infant formula with rice starch by testing in-process samples using rheology. We used DSC to first determine the gelatinization temperature of the rice starch, a key ingredient of this product. With this characteristic temperature and the process design known, rheological measurements were conducted on the in-process samples for detecting the presence and extent of gelatinization and retrogradation of rice starch; in-process samples were collected from the carbohydrate tank, after the homogenizer, and the finished product tank. The correlation between the rheological measurements on these samples and manufacturing performance proved that rheology is a very sensitive tool for monitoring the structural development of this infant formula during main process, and their influence on sterilization efficiency. We observed that the lower degree of gelatinization during main process, a shorter residence time in the finished product tank, and using caustic flush rather than clean-in-place additively lead to higher sterilization efficiency. These findings can be utilized for a rational design and analysis of the manufacturing process for infant formulas containing rice starch.