• Journal of the East Asian Society of Dietary Life
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• v.26 no.5
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• pp.457-465
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• 2016

Effects of soaking time on the physicochemical and structural characteristics of waxy rice flours and starches purified from flours using the alkaline steeping method were investigated. Korean cultivar Sinseonchal waxy rice was washed and soaked in tap water (1:2 w/w) and stored at room temperature for 15 days. On each day of soaking for 0, 1,2 3, 5, 10, and 15 days, pH of soaking water was measured and rice grains were dried, ground, and passed through 100 mesh sieve. The pH was reduced to 3.90 by day 5 and increased to 4.60 by day 15. The protein and ash contents, swelling powers and solubilities of flours and starches decreased with increasing soaking time. The water-binding capacities increased while trends were not similar to soaking time. The flour particle size distribution ranged from two to four peaks with increasing soaking times. Starch granule size decreased with increasing soaking time. The peak, trough, and final viscosities of flours and starches showed similar trends until 10 days and 15 days, respectively. The starches presented higher viscosities than the flours. The branch chain length distributions of amylopectin of starches showed an increaseed DP6~12 portion and decreased DP13~24 portion with increasing soaking time of waxy rice grains.

• Korean journal of food and cookery science
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• v.7 no.4
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• pp.9-13
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• 1991

Nochi is a kind of Korean traditional food made from glutinous rice or millet. This study attempted to examine the effects o( the various factors and to clarify the factors which affect the overall eating quality of Noch. The results were summarized as follows. 1. Starch content of waxy rice was 72.4% and IBC was 0.017%. 2. $\alpha$-amylase and $\beta$-amylase activity of malt were 40.13 and 8.94 units respectively. 3. Waxy rice soaked for 3 hours was ground to flour then sifted 20 mesh sieve. The mixture of waxy rice and malt was steamed for 20 minutes. 4. In sensory evaluation on varying the amount of malt and incubation time, the most favorite tendancy of the overall eating quality was at the level of 8hours incubation made by 5% addition of malt. 5. Total sugar contents, reducing sugar contents and the intensities of iodine stain at the incubation temperature of $60^{\circ}C$ were significantly different from those at $50^{\circ}C$.

• Culinary science and hospitality research
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• v.14 no.4
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• pp.1-13
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• 2008

The antioxidant activity and quality characteristics of bread made from waxy black rice flour(WBRF) and green tea powder were investigated. The bread was manufactured with 1% of green tea powder and 10, 20, 30 or 40% of WBRF(w/w). The group of 40% of WBRF and green tea powder significantly showed the highest bread weight and volume. Lightness(L value) and yellowness(b value) decreased, but redness(a value) increased with increasing WBRF contents in mixture. Hardness, gumminess and chewiness were the lowest in the control group, but springiness was the lowest in the group of 40% of WBRF and 1% of green tea powder. The sensory scores of appearance, external and crumb color, grainy in the group of 40% of WBRF and 1% of green tea powder were the significantly lowest. Overall acceptabilities of the groups of 10% and 30% of WBRF with 1% of green tea powder were not significantly different from the control group. The group of 40% of WBRF and 1% of green tea powder showed the highest DPPH radical scavenging effect and TEAC content. Thus, if the mixture of green tea powder and WBRF would be used, it might be proper to use 1% of green tea powder and 10% of WBRF mixture considering the quality and antioxidant activity of bread.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.878-885
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• 1997

Effect of various ingredients and cooling methods on the quality of modified Jeung-pyun(traditional Korean steamed rice cake) were studied. Three different kinds of wheat flours(strong, medium, and weak) were studied to evaluate the volume and firmness of Jeung-pyun. Weak flour showed the maximum volume and good sensory results. The optimum ratio of ingredients was flour : water ; sugar ; Tak-Ju=100 : 20 : 20 : 50 for steaned Jeung-pyun. When three different cooking methods were compared, the maximum volume showed from convection oven method, but the crust color of Jeung-pyun was like bread. Steaming method showed higher volume than that of product heated by microwave method. The optimum formula ratio for the microwave method was flour ; water ; sugar ; Tak-Ju = 100 : 30 : 20 : 50, which required 10% higher added water content than that of steaming. When wheat flour was used instead of rice flour, the addition of 5% normal corn starch increased volume of both steamed and microwave cooked products. In the case of added modified starches to Jeung-pyn, 5% $\alpha$-waxy corn starch showed the highest volume in steaming method. When rice flour was used, the addition of 5%$\alpha$-waxy corn starch also showed highest volume f both steamed and microwave cooked products. The firmness of steamed wheat flour Jeung-pyun, containing 5%$\alpha$-corn starch was higher firmness than that of control and other added samples. Microwave cooked products showed two or three times higher firmness of steaming products. The use of wrap(uni-wrap) and stabilizer(METHOCEL) decreased the firmness of microwave cooked wheat flour Jeung-pyun to 200~300g compared with that of untreated Jeung-pyun.

• Korean journal of food and cookery science
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• v.22 no.2 s.92
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• pp.147-157
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• 2006

To improve the properties of non-waxy rice flours for baking, soaked-wet milled rice flour (SWRF) was adjusted moisture content (MC) to 30 and 50 % and heated at 50 and $70^{\circ}C$ in a shaking water bath for 6 and 18 hrs, respectively. Moisture-heat treated rice flours were investigated with regard to particle size distribution, and morphological, physicochemical and pasting properties for comparing dry and wet milled flours. The particle size of rice flour treated with 30% MC was distributed between $4-20{\mu}m\;and\;100-200{\mu}m$, like SWRF. The particles above $200{\mu}m$ in the flour were produced at higher heating temperature. By SEM, starch granules were found in the rice flours treated with 30% MC, who whereas aggregated starch granules were shown in the flours treated with 50% MC. Moisture-heat treatment using higher MC and heating temperature decreased the lightness and increased the yellowness of non-waxy rice flours. Water binding capacity of 30% moisture treated rice flour was similar to that of SWRF. In the same moisture treated rice flour, swelling power was higher, but solubility was lower at $50^{\circ}C$ than at $70^{\circ}C$. The initial pasting temperature by RVA increased after moisture-heat treatment. The peak viscosity of moisture-heat treated rice flour was higher for 30% moisture than that of the others. The rice flour treated with 30% MC and heated at $50^{\circ}C$ showed low setback and increased stability for retrogradation.

• Korean Journal of Agricultural Science
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• v.40 no.4
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• pp.377-383
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• 2013

Premature-green rice is typically obtained by early harvest when culms of rice still appear green in color, and the rice and its food products have been considered as wellbeing foods. This study was carried out to determine the quality characteristics of cookies made from flour added with 10, 20, and 30% whole green rice powde r(WGRP) of two kinds of Hopum and Shinsun waxy rice. The quality characteristics of cookies, including pH, spread factor, color, hardness, and sensory properties, were estimated. WGRP with different levels of 10, 20, and 30% was added into powder for preparing cookies, and their quality properties were evaluated. The pH and hardness of the cookies increased, while spread factor showed highest added with 20% Hopum and Shinsun waxy rice. The color (L) of cookies decreased 20% added with Hopum and Shinsun waxy rice. The sensory properties of cookies was highest added with 20% Hopum and 10% Shinsun waxy rice. The result of this study suggest that addition of 20% Hopum and 10% Shinsun waxy rice are available rice cookies. It was concluded that WGRP may have a potential in bakery industry as a new food material.

• Korean journal of food and cookery science
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• v.33 no.2
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• pp.198-208
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• 2017

Purpose: To improve the quality of basic gluten-free rice bread composed of white rice flour, salt, sugar, yeast, skim milk powder, olive oil, and water, the effects of transglutaminase (TGase), whey protein (WP), propylene glycol alginate (PGA), and hydroxypropylmethylcelluose (HPMC) were investigated. Methods: TGase, WP, PGA, and HPMC were added to rice flour cumulatively. The pasting properties of rice flour blends as well as volume, shape, color value, textural properties and sensory evaluation of basic rice bread (RB1) RB1+TGase (RB2), RB1+TGase+WP (RB3), RB1+TGase+WP+PGA (RB4), and RB1+TGase+WP+PGA+HPMC (RB5) were compared. Results: Consistency of rice batter increased upon addition of TGase, WP and PGA, and RB3 and RB4 had higher specific volumes than others. PGA improved volume, crumb air cell uniformity, and resilience but lowered elasticity and moistness of RB. HPMC increased, hardness, moistness and softness, and slightly reduced volume. Conclusion: Therefore, it is suggested that hydrocolloids, PGA and HPMC may be necessary to improve volume, crumb structure, textural properties and overall eating quality of gluten-free rice bread.

• Korean Journal of Human Ecology
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• v.7 no.2
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• pp.149-159
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• 1998

This study was carried out to examine the role soy milk in the preparation of Yukwa, possibility of substitution of soy milk to isolated soy protein and the effect of drying condition of Yukwa dough on the quality of Yukwa for the purpose of standardization of Yukwa preparation process. Although isolated soy protein did not make any particular effect on the gelatinization characteristics of waxy rice flour, soy milk lowered peak viscosity to half of waxy rice flour. The optimum moisture content of dried Yukwa dough was about 25%, and it can be reached by drying at $60^{\circ}C$ under atmosphere pressure for $4{\sim}5$ hours. On the basis of the results of morphological observations, mechanical and sensory measurement of hardness, and sensory test of the internal structure, mouthfeel and overall acceptability, soy milk was more desirable than isolated soy protein for the quality improvement of yukwa.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.8
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• pp.1076-1083
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• 2009

The physicochemical properties of rice flour produced by 3 different grinding methods using various steeping times (3, 6, 9, and 12 hrs) were investigated. Roller mill gave coarse rice flour; the pin mill, intermediate flour; and mixed when both (roller & pin mills) were used. With the increase of steeping times, the rice flours became finer and the contents of crude protein, crude fat and crude ash decreased. Damaged starch was noticeably high in rice flour by roller & pin mills compared to those by roller or pin mills alone. Amylose contents, solubility and swelling power increased as the steeping times increased. Water binding capacity was the highest in roller & pin mills, followed by pin mill. In scanning electron microscope (SEM), pin mill showed distribution of separated fine particles of rice flours. The physicochemical properties of rice flours showed many differences by steeping times of rice and grinding methods. With sufficient steeping times, the rice flours obtained from pin mill were relatively fine having less damaged starch.

• Journal of Food Hygiene and Safety
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• v.16 no.3
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• pp.227-231
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• 2001

Basic materials for various making gangjung, various concentration 0∼25.0%(w/v) of coating agent and 0∼20.0% of substitutional materials carried out an experiment in sensory evaluation, expansion rate and hardness of substitutional materials. The results are as follows: 1. Added coating agent far improvement of decreasing aroma, arabic gum and dextrin significant from 20.0% to 25.0% compared with others. A good results flavor strength score and hedonic score of added 20.0% arabic gum are highest. 2. Expansion rate is caused by substitutional waxy rice, expansion rate decreased above 20.0% as tapioca above 5.0%, rice above 10.0%, brown waxy rice and wheat flour 15.0%. 3. After firing gangjung of substitutional materials, hardness increase concentration of substitutional materials. Therefore substitutional materials added to tapioca below 5.0%, rice and wheat flour 10.0%, brown waxy rice 15.0% is thought of good.