• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.392-398
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• 1988

Gelatinized rice flours were prepared by drum drying at different moisture contents of slurry made from dry milled and wet milled rice flours. Milled rice samples were prepared from the Chuchung and the Samgang varieties. Degree of gelatinization of drum-dried rice flours revealed over 92% at 60% moisture content of wet milled rice flours and 80% moisture content of dry milled ones. With regards to amylogram and rheological properties, drum-dried rice flours prepared from wet milled raw materials showed higher viscosity than from dry milled ones. Increasing water contents in the slurry increased water absorption index(WAI) and decreased water solubility index(WSI). Hunter's color values of drum-dried rice flour at high moisture contents showed higher L values and lower b values. For the preparation of gelatinized rice flours by drum drying process, the higher water content caused more gelatinized network structure of rice starch in scanning electron micrographs. With regards to farinogram properties of dough with drum-dried rice flours and wheat flours in mixing ratio of 1 to 9 by weight, drum-dried rice flours made from wet milled raw rice flours revealed higher MTI than from dry milled ones.

• Korean journal of food and cookery science
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• v.11 no.5
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• pp.479-486
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• 1995

The reological properties of doughs blended with cereal flours were investigated in the study. The doughs were prepared of wheat flours mixed with 10％, 20%, 30% and 40% ratio of rice flour, waxy-rice flour, brown-rice flour and soybean flour. Amylogram, farinogram, extensogram and SEM were used to measured thier special properties with graphs and photos. The results were obtained as followes; 1. Wheat dough formation after fermantation, showed "stringing" structure of small starch granules on the SEM photo. But the large starch granules contributed little to the structure formation in rice flours dough, and played relatively a little role in the structure formation of blended doughs of waxy-rice, brown-rice and soy- bean flours. 2. The absorption of flour composited rice and brown-rice, was lower than that of the control by Farinograph. It was decreased the farinograph absorption with the increase of replacement ratio of cereal flours. Dough development time of cereal blended flours decreased, but that time of waxy-rice and brown-rice were very similiar. Farinograph stability of rice, waxy-rice, brown-rice and soybean blended flours, had shorter than that of wheat-flour. 3. The results showed that cereal blended flours decreased the resistance to extention (elasticity) without affecting the extensibility in fermented dough by Extensograph. 4. The gelatinization temperature of wheat, rice, waxy-rice, and brown-rice were 55.0$^{\circ}C$, 64.0$^{\circ}C$, 58.0$^{\circ}C$ and 61.0$^{\circ}C$. But that of all cereal blended flours showed 58.0$^{\circ}C$ except 20% or 30% soybean blended flours. According to the amylogram, each maximum viscosity of rice flour and wheat flour was 1760 B.U.,760 B.U.. Soybean composite flours had significantly lowe. amylograph peak viscosity (300 B.U.) than that of the other composite flours (450 B.U.-1100 B.U.).

• Korean journal of food and cookery science
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• v.9 no.3
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• pp.210-214
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• 1993

This investigation was undertaken for the purpose of studying the physicochemical properties of rice flour made by various soaking time(1,4,6,8,12 hours) of rice. As the soaking time was longer, the lightness of rice flours increased, on the contrary its redness and yellowness decreased. Rice flours had higher swelling power and solubility by increasing soaking time, but water binding capacity decreased upon soaking of rice. Hot water insoluble amylose of rice flours was decreased, whereas hot water soluble amylose was increased as the soaking time increased. The amylograph indices indicated that initial pasting temperature of rice flours decreased, while maximum viscosity increased as the soaking time increased.

• Korean journal of food and cookery science
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• v.19 no.2
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• pp.136-143
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• 2003

This study was carried out to investigate the quality of bread made with different types of brown rice flours. 20% of the wheat flour from the bread recipe was substituted with the different types of brown rice flours, such as, raw brown rice flour (RBRF), soaked brown rice flour (SOBRF), and sprouted brown rice flour (SPBRF). The loaf volume of the bread: decreased by 3.2%∼7.4% with the addition of the brown rice flours. The "L" value of these breads decreased, while the "a" and "b" values increased. In terms of the texture, the SPBRF bread was the hardest on the 1st day of storage, but it was the least hard on the 5th day of storage. The RBRF bread was the least springy. The SPBRF bread was the most cohesive. The adhesiveness was not significantly different among the breads. In terms of the degree of retrogradation using the ${\alpha}$-amylase method, the SOBRF and SPBRF breads showed a little lesser degree of retrogradation than the control and the RBRF bread. In the sensory evaluation, the control bread obtained high score for crumb color and grain, while the brown rice flours breads obtained high scores for mouthfeel and taste. Overall acceptability, defined by a higher score, was higher for the SOBRF and SPBRF breads than the control bread, which was not significant. Thus, this study showed that processing rice flour was more effective than raw rice flour in substituting wheat flour.

• Korean journal of food and cookery science
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• v.26 no.6
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• pp.727-736
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• 2010

The purpose of this research was to compare the physicochemical compositions and morphological properties of five varieties of rice flours (RR, RGD, RSGD, RWDG, RWGD). RR was raw milled rice without washing, RGD was raw rice flour without soaking, RSGD was raw milled rice flour with 0 hr of soaking, RWDG was raw rice flour with 8 hr of soaking and grinding after drying, and RWGD was raw rice flour with 8hr of soaking and drying after grinding. The protein and lipid contents of wet milling rice flour (RSGD, RWDG, RWGD) were significantly lower than those of dry milling rice flour (RR, RGD). L and a values were significantly increased in wet milling rice flour, and b value was significantly increased in dry milling rice flour. Scanning electron microscopy (SEM) showed that RWDG and RWGD were distributed as separated fine particles in rice flours. The WBC of RWDG and RWGD were higher than those of other rice flours. Solubility was significantly increased according to the temperature, and swelling power of RWDG was higher than that of other rice flours at 50 and $60^{\circ}C$. Using RVA, the initial pasting temperature and setback of RWDG were lower and the peak viscosities of RSGD and RWDG were higher than those of other rice flours. Using a mixograph, peak times were not significantly different among the groups, wheras peak heights were significantly decreased in RSGD, RWDG, and RWGD. The peak width of RWGD was lower than those of other rice flours. Based on these findings, RWDG flour was less damaged, and had a lower setback and pasting temperature, which makes it an appropriate rice flour for commercial mass production.

• The Korean Journal of Food And Nutrition
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• v.30 no.4
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• pp.635-643
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• 2017

The properties of rice were studied, and 8 rice flour cultivars were used to study the effect of particle size on the physicochemical properties, color value, RVA viscosities, water absorption index (WAI), and water solubility index (WSI) of rice flours. The mean particle size by the 3 particle size classification of 150 mesh, 200 mesh, and 250 mesh was, $90.75{\mu}m$, $60.73{\mu}m$, $39.94{\mu}m$, respectively. Thai rice had the highest amylose content and Samkwang rice had the lowest amylose content. Protein content of rice flours prepared was decreased as the particle size of rice flour decreased. In terms of color values, the L-value and the a-value of rice flour were increased as the particle size of rice flours decreased, while the b-value was decreased as the particle size of rice flours decreased. Using a rapid visco analyzer (RVA), the initial pasting temperature of Thai rice cultivar was found to be the highest; the peak viscosities of Sunpum cultivar and Misomi cultivar, and Samkwang rice were higher than those of other rice flours. The water absorption index and water solubility index were increased as the particle size of rice flour decreased. In order to use processed rice flour for the development of processed foods, proper characteristics of the cultivars and particle size should be considered.

• Korean Journal of Rural Living Science
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• v.7 no.1
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• pp.31-37
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• 1996

This experiment was carried out in order to investigate milling methods of rice flours on characteristics of rice-cinnamon cakes. The expansion ratio and cake volume of hydrated rice flour was the better than the non-hydrated rice flours. The rice-cinnamon cake of the hydrated riceflour was generally alike in texture and taste to the cake of wheat flour as the result of Instron and sensory evaluation. The rice - cinnamon cake of the non - hydrated rice flour was generally lower in aircell and texture to the cake of the hydrated rile flour.

• The Korean Journal of Community Living Science
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• v.21 no.4
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• pp.509-515
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• 2010

The physicochemical properties of the lactic acid fermented rice flour prepared using ABT-L(mixture of Lactobacillus acidophilus, Bacillus longum, Streptococcus thermophilus) were investigated. The efficiency of deproteinizing of lactic acid fermentated rice was higher than soaking fermented rice. The structural properties of lactic acid fermented rice flour showed slightly decreased inner particle size but maintained regular structural form. Molar mass and molar size after being treated with soaking or lactic acid fermentation were decreased. Amylograms except for pasting temperature of lactic acid fermented rice flours or soaking fermented rice flours were more significantly decreased than the control sample. The ratio of flours passed through 100 mesh and 150 mesh sieves of lactic acid fermented rice flours were higher than soaking fermented rice flours. Lactic acid fermented rice flours being passed through 100 mesh sieves showed finer particle flours than those treated with soaking. These results showed that lactic acid fermentation, which can have a high efficiency on the deproteinizing of rice, contributed to the changes of particle size and its distribution of rice flour.

• Korean Journal of Human Ecology
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• v.5 no.2
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• pp.33-43
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• 2002

This study was investigated textural properties of Injulmi affected by milling methods, varieties and added water volume. Sinsunchalbyeo and Hwasunchalbyeo flours were made using Rin-dry milling(PDM) and roll-wet milling(RWM) methods. The proximate composition of waxy rice starches and waxy rice flours were similar. Water binding capacity, soluble carbohydrate and damaged starch of waxy rice flour by RWM: were higher than those of waxy rice flours by PDM. By increasing added water volume, hardness and adhesiveness of Injulmi were decreased. By increasing storage time, hardness of Injulmi was increased, but adhesiveness was decreased. The hardness of Injulmi made from waxy rice flours by PDM was higher than by RDW.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.690-696
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• 1995

Properties of dry milled rice flours made of paddy with different moisture content (12.6, 18.4 and 24.4%) were compared with those of wet milled rice flour. Among dry milled rice flour, the higher moisture content of paddy the finer particle size and the more distinct shape of starch were observed. As the moisture content of paddy increased, L (lightness) value and water absorption index of rice flour were increased, while setback in amylogram and water soluble index were decreased. Lower gel consistency and gel strength were found in dry milled rice flours than in wet milled rice flour, while no significant difference was found among dry milled rice flours. Enthalpy for melting crystalline of retrograded gels was higher in dry milled rice flours made of paddy with 24.4% moisture content than in other dry milled rice flours. Wet milled rice flour had lower retrogradation enthalphy than dry milled rice flours.