• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.886-890
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• 2006

Rice flours produced by dry, wet, and semi-wet milling methods were used to investigate bread-making properties. Wet milled rice flours were produced by two different steeping temperatures of $25^{\circ}C$ and $55^{\circ}C$, properties of composite flour containing 70% rice flour and 30% wheat flour with the addition of vital wheat gluten were tested. Among rice flours, wet milled rice flour showed increased mixing time and dough stability determined by a mixograph. Wet milled rice flours produced higher loaf volume compared with dry of semi-wet milled rice flours. Wet-milled rice flour steeped at $55^{\circ}C$ appeared to produce good rice breads with relatively high loaf volume. Crumb hardness of bread prepared with wet milled rice flour was lower than the other breads and increased slowly during 3-day storage at $25^{\circ}C$.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.3
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• pp.414-419
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• 2005

Newly harvested milled rice and stored milled rice for 2 years were steeped at the elevated temperatures of 40, 50, and 60℃ for 2hr, and physicochemical properties of the wet-milled rice flour were investigated. The lightness of rice flour was slightly higher in the newly harvested milled-rice, while yellowness was higher in the stored milled rice. For both newly harvested and stored milled rice, WAI, WSI, and gel consistency increased as steeping temperature increased. The amylograph pasting properties indicated that increasing steeping temperature increased peak viscosity. The differential scanning calorimetry (DSC) results of the rice flour showed that increasing steeping temperature increased onset and peak temperatures, with reduced gelatinization enthalphy, suggesting partial annealing occured. Particle size of rice flour from newly harvested milled rice was larger than that from stored milled rice.

• 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.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.759-764
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• 2007

To investigate the effect of soaking and particle sizes on the properties of rice flour and gluten-free rice bread, wet-milled (WRF, dried at $20^{\circ}C$) and dry-milled rice flours (DRF) were passed through sieves (45 or 100 mesh). Soaking of the rice grains affected the particle size distribution of flour passed through the same size screen. The L and b values of WRF were higher than those of DRF and were not changed with decreasing particle sizes, but DRF increased L and decreased b values. The initial pasting temperatures and setback viscosities of both flours decreased with decreasing particle sizes. The swelling powers at $100^{\circ}C$ increased with decreasing particle sizes in DRF, but maintained in WRF. Starch granules were observed on the surface of flour particles in WRF. The apparent viscosity of WRF paste exhibited 3-5 times higher than that of DRF. Thus, wet milled rice flour with smaller particle sizes (${\phi}<150\;{\mu}m$) showed better properties for making gluten-free rice bread.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.12
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• pp.1797-1801
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• 2011

Two brown rice samples differing in amylose content, 20.1 (normal) and 7.3% (low amylose) were milled by different milling methods, and their physicochemical properties were tested. Particle size of brown rice flour prepared by dry milling using a pin mill (DM) was lower than that prepared by wet milling using a roll mill (WM). Particle size was further reduced by successive dry milling of the flour after wet milling and drying (WM/DM). Damaged starch contents in the wet milled brown rice flour were 14.6 and 15.6% for the normal and low amylose samples, respectively, whereas they were only 4.2 and 4.8% for the dry milled samples. WM/DM method resulted in a lower damaged starch (%) than DM, despite a reduced flour particle size. Water absorption index (WAI) of the brown rice flour was the lowest after WM/DM, and the water solubility index (WAI) was higher in the order of DM, WM/DM, and WM. Brown rice flour with normal amylose content appeared to have significantly higher pasting viscosities, as determined using a Rapid Visco Analyzer (RVA). Compared to dry milled brown rice flour, wet milled brown rice flour showed lower peak viscosity and higher final viscosity, resulting in increased setback value.

• Food Science and Preservation
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• v.22 no.2
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• pp.174-181
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• 2015

This study investigated the physicochemical properties of three different types of rice flour prepared via dry and wet milling. The powder, soft, and hard-types of rice flour were Suwon No. 542, Suwon No. 541, and Unbong No. 30, respectively. The analysis of the proximate compositions of the different types of rice flour showed that their moisture content was 7.03~7.99%, their crude protein was 7.94~8.35%, their crude lipid was 0.71~1.49% and their crude ash was 0.25~0.82%. For the Hunter's color values, the L value was highest in the wet-milled rice flour, the a value was highest in the dry-milled rice flour, and the b value was highest in the dry-milled rice flour. All the samples showed distinctive rice starch particles in the particle analysis using scanning electron microscope. The dry-milled rice flour showed the greatest amount of irregular particles and the coarsest texture. The water absorption and water solubility indices were higher in the wet-milled soft- and hard-type rice flour. The crystallinities of the samples by X-ray diffractography were all A-type, but the crystallinity of the dry-milled hard-type rice flour was higher in diffraction degree. For the amylogram properties, the wet-milled soft-type rice flour showed the highest maximum viscosity, breakdown and setback. In the meanwhile, the dry-milled soft-type rice flour showed the highest initial pasting temperature, onset, peak, and end temperatures despite of the reverse enthalpy.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.276-276
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• 2017

This study was examined to establish a conditions for producing Tteokbokki using dry-milling rice flour which can save manpower and labor time. Since the cost of producing rice flour milled in a wet condition is 500 to 700 won/kg, which is more than twice as much as that of 300 won wheat flour, it is necessary to directly make rice flour from raw rice. The dry-milling rice flour used in the experiment was produced by Air mill (Nara machinary co. ltd., Tokyo, Japan) from 5 rice cultivars (Samkwang, Dasan-1, Boramchan, Seolgaeng, Hanareum-2), which were cultivated in A-san in 2015 year. Their particle sizes were 50, 100 and $150{\mu}m$ for each cultivar, respectively. A control was a wet-milled rice flour milled with a roll mill after the rice was soaked in water for 4 hours. The moisture content of dry-milling rice flour based on cultivars was 11 ~ 12%, and added water up to 50~55% of dry-milling rice flour weight. The RVA characteristic of peak viscosity was the highest in Dasan-1 and Hanareum-2, the lowest in Seolgaeng. The setback value used as an indicator of aging was the highest in Dasan-1, therefore Dasan-1 was expected to be quick solidification, resulting in the low tendency of sensory evaluation. The damaged starch was high in Dasan-1 and Boramchan (p<0.05) compared to others. The Hunter color L were no significant among cultivars and b value increased in all cultivars of dry-milling rice flour compared with control. The hardness of dry-milling rice flour was higher than that of the control, especially Dasan-1 and Hanareum-2 were the highest. Based on the sensory evaluation, the best cultivars were Boramchan, Hanareum-2 and Samkwang. The overall preference of dry-milling rice flour was good in particle size of 50~100um.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.637-643
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• 2012

This study was performed to increase the utilization of rice and improve the productivity of jochung, traditional food in Korea. Two kinds of jochung products were prepared from steamed rice(SR) and wet-milled rice flour(WRF) by rice cultivated from 2006 to 2010. It is common to add a liquefying enzyme for rice liquefaction(4 $m{\ell}$/1,000 g rice, at $90{\sim}95^{\circ}C$, 3 h) and saccharogenic enzyme with malt(45 g/1,000 g rice, at $55{\sim}57^{\circ}C$, 6 h). In order to evaluate the quality characteristics of jochung, producing rate, pH, solidity, reducing sugar, dextrose equivalence(D.E.), viscosity, total phenolic compound, color value and sensory evaluation were carried out. In terms of the producing rate of jochung, WRF jochung was produced about 7.4% much more than SR jochung. There was no difference in producing rate between the jochung cultivated from 2006 to 2010 rice. The pH varied from 4.86~5.66, solidity was 79.48~82.28%. Color L value was 25.82~27.92, a value of 1.28~2.81, b value were 2.98~4.33. The results of sensory evaluation for jochung, as a whole, received higher score than for the commercial product(Daesang Co., Ltd, Seoul, Korea), overall acceptability score was the highest in the 2008SR. Reducing sugar, dextrose equivalence(D.E.) and total phenolic compounds were determined to be higher WRF jochung than SR jochung, while viscosity was lower WRF jochung than SR jochung. These results are thought to be due to increased surface area of rice by milling. SR jochung manufacturd by wet-milled rice flour will increase the producing rate for jochung, thereby saving manufacturing time and costs.