• Food Engineering Progress
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• v.15 no.3
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• pp.195-202
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• 2011

Physiological characteristics of brown rice and black rice were investigated to provide the fundamental information of physiological property of rice and to show the potential of rice as a functional ingredient. Bioactive compounds were extracted from brown and black rices with aqueous solvents like 80% ethanol. Total phenolics, flavonoids and antioxidative capacity of brown and black rices' extracts were determined. Brown rice showed much higher amount of total phenolics and flavonoid contents as well as antioxidative capacity than those of milled rice indicating that most of bioactive compounds are located in the bran layer. Black rice showed higher total phenolics and flavonoid contents and antioxidative capacity than those of brown rices. The highest antioxidative capacity was obtained from Heugjinju followed by Heugseol, Sinnongheug-chal, Hopum and Samkwang. This result indicated that antioxidative capacity is affected by total phenolics and flavonoid contents. Both brown and black rices contained higher amount of ferulic acid than that of p-coumaric acid.

• Applied Biological Chemistry
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• v.44 no.1
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• pp.30-34
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• 2001

Physicochemical properties of milled rice, brown rice, pearled barley, wheat, sorghum, foxtail millet, soybean, and adzuki bean were evaluated for the production of extrusion formed multi-grain. Grain flours showed large differences in chemical composition including starch, protein, fat, ash, and total dietary fiber contents. Grain flours were brighter in the following order of milled rice>pearled barley>soybean>brown rice>wheat>sorghum>adzuki bean>foxtail millet, and most of the grain flours showed red-yellowish color. Mean particle sizes of grain flours were different among various grains, and whole grain flours tended to have coarser particle size than milled grain flours. The amounts of damaged starch in cereal flours were varied from 5.4 to 10.9%, and limited amount of damaged starch was present in legume flours. Water absorption index of grain flours was, in decreasing order, adzuki>bean>milled rice>brown rice>sorghum>wheat>foxtail millet>pearled barley>soybean. Water solubility index was higher in legume flours containing high protein content.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.spc1
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• pp.29-32
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• 2005

This experiment aimed to estimate the effect of imperfect rice on rice palatability. Rice cultivar, Ilpumbyeo, was cultivated by direct-seeding on flooded paddy surface with 11 kg/10a nitrogen application. Palatability of harvested rice was measured by NIR spectroscope. Brown rice was divided according to their appearance namely, perfect, discolored, green-kerneled, and immature opaque with a composition ratio of $75.7\%,\;11.0\%,\;8.0\%,\;and\;5.3\%$ respectively. When the perfect brown rice was milled, the grain were composed of head, cracked, and white core & belly, at $64.7\%,\;25.3\%\;and\;10.0\%$ respectively. The milled rice of discolored brown rice had similar composition with the perfect rice. The milled green-kerneled vice, on the other hand, had $36\%$ head rice and $64\%$ white core & belly rice. The immature opaque brown rice, when milled, had $25.3\%$ white core & belly and $74.7\%$ damage & opaque rice. With the respect to grain quality, the viscosity of white core at belly rice and damaged & opaque rice was lower than that of head rice. In contrast, their protein content was a little higher than that of head rice. The palatability value of pure imperfect rice was much lower than head rice. The palatability value of damaged & opaque rice was the lowest among the imperfect rices. When mixed with head rice, the damaged & opaque rice impacted on the deterioration of vice palatability. Mixing $1\%$ each of white core at belly rice and damaged h opaque rice decreased the palatability value by $5\%$ as compared with the head rice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.5
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• pp.600-607
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• 1996

Colored rices have been used for specific purposes by rice consumers due to the color and nutritive values empirically recognized. In this study, varietal variations of pigmentation and nutritive values were investigated in brown, red, purple and black rices. Pigments were localized in seed coat to pericarp region in all varieties tested. Pigments were slightly residued on the surface of milled rice. Anthocyanin content per g brown rice was 1.63~17.62 $\mu\textrm{g}$ in brown and reddish-brown rices, 3.56~11.10 $\mu\textrm{g}$ in red rices, 28.11~401.22 $\mu\textrm{g}$ in purple rices, and 3, 665.98 $\mu\textrm{g}$ in a black rice. A vatiety DZ 78 showed the highest protein content out of colored rices analyzed for protein. Normal and colored rices were found to have the similiar composition of amino acids, and so was in between brown rice without embryo and milled rice. Colored rices, L $K_1$B-4-12-1-1 and DK 1, showed higher content of vitamin $B_1$ compared with Hwacheongbyeo, a check variety of no specific color, and L $K_1$B-2-1-1 and L $K_1$B-4-12-1-1 showed much higher content of vitamin B2 in brown rice without embryo. Cation contents such as $K^{+}$, $Mg^{2+}$, $Ca^{2+}$ and F $e^{2+}$ were significantly increased in most of the colored rices tested implying that the increase might be associated with color pigmentation.ation.

• Korean Journal of Food Science and Technology
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• v.51 no.3
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• pp.214-220
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• 2019

Four rice varieties (Boseogchal for waxy, Baegjinju for medium-waxy, and Seolgaeng and Haiami for non-waxy) were milled to 2% degree of milling (DOM), and physicochemical and sensory properties of 2% milled rice (2% MR) were compared to those of brown rice (BR). No significant differences in the approximate compositions of BR and 2% MR were observed, whereas the grain color of 2% MR was slightly brighter than that of BR. For all varieties, water absorption ratio of BR was significantly increased by milling. The pasting properties of rice varied significantly depending on the variety, but there was no significant difference in peak and through viscosities between BR and 2% MR. Analysis of the texture of cooked rice showed that milling to 2% DOM caused a significant decrease in hardness, but an increase in adhesiveness and stickiness. Cooked Seolgaeng 2% MR scored significantly higher in the sensory evaluation than the corresponding BR. These results suggest that 2% DOM would be useful for improving the sensory properties of cooked non-waxy rice.

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.850-854
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• 2012

This study is carried out in order to develop food materials for the promotion of rice consumption. In this study, we researched the physicochemical properties of extruded rice flour (ER) and gelatinization popped rice flour (GPR) by the extrusion process and by the popped method with milled rice and brown rice. The extrusion process used a couple of screw extruders. The extrusion parameter was kept constant at a feed moisture content of 25%, barrel temperature of $120^{\circ}C$ and screw speed of 400 rpm. GPR was prepared by batch popping machine after gelatinization of rice. In order to evaluate the physicochemical properties of ER and GPR, as well as the gelatinization rate, water soluble index (WSI), water adsorption index (WAI), DPPH radical scavenging activity and total dietary fiber content, the color value was carried out. The gelatinization rate was similar to 71.1~73.8%. Further, the results of WSI and WAI were increased at ER and GPR compared to the raw materials; ER was also higher than GPR. DPPH radical scavenging activity and total dietary fiber content showed a tendency to reduce after extrution and popping. As a result of the color value, the L value of ER decreased more than the raw materials, whereas GPR increased at a and b values.

• Korean Journal of Agricultural Science
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• v.44 no.3
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• pp.416-423
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• 2017

This study aimed to identify milling characteristics depending on the rotating speed of the main shaft of the cutting-type rice milling machine which can minimize the conventional milling process. Brown rice, which was produced in Gunsan-si, Jeollabuk-do, Republic of Korea, in 2016, was used as the experimental material. The milling characteristics of white rice were measured under four different rotating speeds of main shaft: 950 - 1,050 rpm, 1,000 - 1,100 rpm, 1,050 - 1,150 rpm, and 1,100 - 1,160 rpm. For each shaft speed, 300 kg of brown rice was processed, and the milling characteristics were measured according to the whiteness, grain temperature, cracked rice ratio, broken rice ratio, turbidity, and energy consumption. The whiteness of rice grain was found to be consistent at around $40{\pm}0.5$ only when milled at the shaft speed of 950 - 1,050 or 1,000 - 1,100 rpm. The grain temperature during the milling process increased by 11.35 to $11.85^{\circ}C$, showing little differences amongst shaft speeds. The cracked rice ratio increased by 8.2 to 10.4% at all conditions. The broken rice ratio ranged from 0.58 to 0.76%, reflecting a low level. The turbidity after milling was 54.8 ppm when milled at 1,000 - 1,100 rpm. Energy consumption of 12.98 and 12.18 kWh/ton were recorded at the shaft speed of 1,000 - 1,100 and 1,050 - 1,150 rpm, respectively. The result of this study indicates that the optimal rotating speed of main shaft would be 1,000 - 1,100 rpm for a cutting-type rice milling machine.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.286-286
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• 2022

The properties of starch play an important role in determining the palatability of rice. In addition, the gelatinization temperature (GT) of rice starch is an important factor in determining the quality of rice because it is related to the cooking time and texture of rice. For the development of high-quality rice, it is important to understand the genetic basis of palatability-related traits, and QTL analysis is an effective method to explain the genetic basis of variation in complex traits. QTL mapping related to alkali digestion value (ADV) of brown and milled rice was performed using the 120 Cheongcheong/Nagdong double haploid (CNDH) line. As a result, 12 QTLs related to ADV were detected, and 20 candidate genes were selected from the RM588-RM1163 region of chromosome 6 through screening by gene function analysis. The comparison of the relative expression level of candidate genes showed that OsSS1q6 is highly expressed in CNDH lines with high ADV in both brown rice and milled rice. In addition, OsSS1q6 has high homology with starch synthase 1 protein, and interact with various starch biosynthesis-related proteins, such as GBSSII, SBE, and APL. Therefore, we suggest that OsSS1q6 identified through QTL mapping could be one of the various genes involved in the GT of rice by regulating starch biosynthesis. This study can be used as basic data for breeding high-quality rice and provides a new genetic resource that can increase the palatability of rice.

• Korean Journal of Food Science and Technology
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• v.38 no.4
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• pp.506-512
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• 2006

We investigated changes in the physicochemical characteristics and functional components of the Saengsik cereal grains-milled rice, brown rice, glutinous rice, and barley- by washing with electrolyzed water. There were no changes in the composition of all cereal grains that was dried with hot-air and freeze-dried after being washed with electrolyzed water. The L and a values were not affected by drying in milled rice, brown rice, glutinous rice, or barley, but the b value increased in milled rice and glutinous rice-this increase was greater with hot-air drying than with freeze-drying. The dietary fiber content of the all cereals increased with hot-air drying. The niacin content decreased in all cereals; the extent of this change was greater with hot-air drying than with freeze-drying. The ${\beta}-glucan$ content of barley was higher in samples that underwent freeze-drying than in those treated by hot-air drying, but was not affected by washing with electrolyzed water. Thus, other than a change in color for milled and glutinous rice, no changes in the physicochemical characteristics and functional components these products were observed with freeze-drying. Data indicate that the electrolyzed water washing could be effectively used as pasteurization step in the uncooked cereal grains.

• Korean Journal of Plant Resources
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• v.30 no.1
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• pp.38-49
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• 2017

The objective of this research was to develop Near-Infrared Reflectance Spectroscopy (NIRS) model for amylose and protein contents analysis of large accessions of rice germplasm. A total of 511 accessions of rice germplasm were obtained from National Agrobiodiversity Center to make calibration equation. The accessions were measured by NIRS for both brown and milled brown rice which was additionally assayed by iodine and Kjeldahl method for amylose and crude protein contents. The range of amylose and protein content in milled brown rice were 6.15-32.25% and 4.72-14.81%, respectively. The correlation coefficient ($R^2$), standard error of calibration (SEC) and slope of brown rice were 0.906, 1.741, 0.995 in amylose and 0.941, 0.276, 1.011 in protein, respectively, whereas $R^2$, SEC and slope of milled brown rice values were 0.956, 1.159, 1.001 in amylose and 0.982, 0.164, 1.003 in protein, respectively. Validation results of this NIRS equation showed a high coefficient determination in prediction for amylose (0.962) and protein (0.986), and also low standard error in prediction (SEP) for amylose (2.349) and protein (0.415). These results suggest that NIRS equation model should be practically applied for determination of amylose and crude protein contents in large accessions of rice germplasm.