• Journal of Applied Biological Chemistry
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• v.51 no.6
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• pp.277-284
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• 2008

The objective of this study was to investigate the effect of soaking time on physicochemical properties of waxy rice, waxy rice flour and waxy rice starch. Waxy rice (WR), waxy rice flour (WRF), waxy rice starch (WRS) were soaked at $18^{\circ}C$ for 14 days and dried at $40^{\circ}C$. Dried samples were grounded and sieved using 180 mesh. Physicochemical properties of the three samples, such as swelling power, solubility, moisture sorption isotherms and pasting properties using rapid visco analyzer (RVA) and crystal pattern using X-ray diffractometer were determined. In all samples, soaking time greatly influenced moisture sorption isotherms but no typical pattern was shown. Swelling power was not greatly changed by soaking time in the three samples. Solubility increased with increasing soaking time in all three samples, indicating that some soluble particles were exuded during soaking. In RVA pasting properties, WR and WRF showed a similar pattern, while WRS showed different pasting properties, suggesting that rice protein plays a significant role in pasting properties. X-ray diffraction patterns of all three samples showed typical A-type crystal pattern suggesting that soaking did not affect crystalline region of samples.

• Preventive Nutrition and Food Science
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• v.16 no.1
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• pp.62-66
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• 2011

Functional foods play an important role in daily diet, human health and the food industry. Hemp was reported to have many advantages for nutritional and medicinal usage. In this study, extruded hemp-rice (EHR) flour, containing 30% hemp, was mixed with the wheat flour to create bread loaves at the concentrations of 5, 10 and 15%. Bread made from 100% wheat flour (with no added EHR flour) was used as a control. The physical parameters, including expansion ratio, specific volume and crust/crumb color were evaluated separately. In addition, changes in hardness of the bread during storage at ambient temperature for 3 days were also studied. The results showed that 10%-EHR bread exhibited the highest hardness value, while 15%-EHR bread presented the lowest. The bread containing EHR flour had lower specific volume and bigger air cells compared to the control. Moreover, the crust and crumb color of EHR-containing bread was significantly darker than those of the control. In this study, the 15%-EHR bread showed higher specific volume, lower hardness and bigger air cell structures.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.9
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• pp.1356-1363
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• 2015

The purpose of this study was to investigate the quality characteristics of instant rice noodles made from rice flour with different harvest times rice processed products. The physicochemical characteristics of three different types of rice flour were investigated, including common rice flour (CRF, harvested in 2012), stored rice flour (SRF, harvested in 2008) and CSRF (CRF mixed with SRF). Instant rice noodles were manufactured with the three types of rice flour, and their quality and sensory characteristics were investigated. The water-binding capacity of rice flour was highest in CSRF. Regarding setback on RVA pasting viscosity, SRF and CSRF showed higher values than CRF. Water absorption after cooking of instant rice noodles was highest in common rice noodles (CON). The volume after cooking of instant rice noodles increased in rice noodles with stored rice flour (SRN). Turbidity of rice noodles using CSRF (CSRN) was higher value than that of CON. In texture properties, CON displayed the highest hardness, adhesiveness, springiness, and chewiness. In the sensory evaluation, overall acceptability values of CON were significantly higher than those of other rice noodles (SRN and CSRN). It was concluded that rice noodles with stored rice flour have increased turbidity with reduced texture and overall preference. This study suggests that addition of CRF may result in significantly increased overall quality of instant rice noodles prepared by SRF.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.1
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• pp.17-24
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• 1997

The effects of steeping on the physicochemical and gelatinization characteristics of glutinous rice flour and its starch were studied. Steeping conditions were 1 day at 25"C,7 days at 2iC and 7 days at 35"C. Crude protein, lipid and ash content were decreased br steeping. It was observed with scanning electron microscopy that endosperm cell wall of glutinous rice flour was diminished by steeping. Although morphology of the glutinous rice starch granules was not affected, the size was decreased by steeping. Density and water binding capacity(WBC) of glutinous rice flour and its starch were changed by steeping. X-ray diffraction pattern of glutinous rice starch was A type and was not affected by steeping. Swelling power of glutinous rice flour and its starch was increased but solubility was decreased by steeping. In Brabender amylographic examination, peak viscosity of untreated glutinous rice flour was very low and increased enormously by steeping resulting in the similar Brabender viscosity pattern to its starch. The gelatinization temperature examined by X-ray diffractometry was lowered by steeping. And the degree of gelatinization under the conclusion temperature increased with increasing of steeping Period and temperature.mperature.

• The Korean Journal of Food And Nutrition
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• v.24 no.4
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• pp.649-656
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• 2011

In this study, we made Sulgidduk with commercialized dried nonglutinous rice flour and different levels of soybean curd. For physical properties of the bean curd-Sulgidduk, its water content was increased significantly with a growing addition of soybean curd. In chromaticity, its L value(brightness) and a value(redness) were decreased significantly with more bean curd while b value(yellowness) went up in Sulgidduk with a large amount of rice flour but went down significantly in the Sulgidduk with a small amount of it. Its hardness of texture was found to be the highest in the Sulgidduk with the most dried nonglutinous rice flour and it tended to be higher with more rice flour and less soybean curd. For cohesiveness, it was recorded to be the highest in the Sulgidduk without soybean curd and showed a tendency of decreasing by adding the bean curd but increased later significantly. In addition, its springiness and brittleness became larger with addition of more dried nonglutinous rice flour. From these results, the best ratio of the bean curd-Sulgidduk to increase nutrition and absorption and to satisfy physical and sensory properties, was 420 g to 500 g of soybean curd to dried nonglutinous rice flour. Moreover, it was considered to decline the calorie of Sulgidduk by adding soybean curd as a material and to contribute to its commercialization by extending storage and preservation time of soybean curd with a short expiration date.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.45-49
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• 2001

This research was conducted to study the characteristics of the extruded products prepared from blends containing fixed amounts of frozen pollack (20%) and defatted soy flour (5%) and varying amounts of rice and corn flour using laboratory-scale single-screw extruder. Extrusion conditions were set at 27% feed moisture, $160^{\circ}C$ process temperature and 170 rpm screw speed. Results showed that there was almost no difference in proximate compositions among all extruded products. The product made from 100% rice flour had the highest expansion ratio, the lowest bulk density and the lowest shear force (P<0.05). Also, this product was the highest in L value and had the highest preference in sensory evaluation. Consequently, the addition of frozen pollack and defatted soy flour to rice flour could make desirable expanded extruded products. This study will form the basis for future development of rice snacks containing frozen pollack.

• The Korean Journal of Food And Nutrition
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• v.23 no.2
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• pp.162-170
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• 2010

This study investigated the effect of addition of pumpkin on the physicochemical properties of rice sponge cakes. Water retention capacity(WRC) was lowest in control preparations to which no pumpkin flour was added. WRC increased as more pumpkin flour was added and rice flour with 25% of added pumpkin flour showed a WRC of 89.0%. Similar to WRC, alkaline water retention capacity(AWRC) also increased as more pumpkin flour was added and ranged from 69.7% to 80.7%. As the amount of pumpkin flour added increased, the pH increased. Similar to the sedimentation value, the Pelshenke value also increased as the amount of the added pumpkin flour increased. The gelatinization temperature did not vary significantly between the samples(p<0.05). The midline peak height, which is the height of the peak point from the baseline, showed the same tendency with that of the midline peak time, but was not significantly different between samples(p<0.05). Volume was decreased as the amount of the added pumpkin flour increased. The weight of the rice sponge cakes showed significant difference increasing with the increasing added pumpkin flour(p<0.05). There was significant difference as the specific loaf volume decreased with the increasing pumpkin flour(p<0.05).

• Preventive Nutrition and Food Science
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• v.4 no.1
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• pp.1-5
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• 1999

Seven rice varietes(Suweonjo, Suweon232 , BG276-5, IR44, IR41999-139, Suweon230 and Yongjubyeo) were used to study the influence of amylose content and particle size on the physicochemical properties of rice flours. Suweonjo has the highest amylose content (27.1% amylose content) had the finest flour particle as supproted by scanning electron microscopy (SEM). Suweonjo had the highest value in hardness of rice grain but the lowest length/width ration. There were no significant differences in color values among the rice flours. Data of brabender visco/amylograph was not associated with amylose content. Yongjubyeo had the highest maximum viscosity and breakdown value while Suweonjo had the lowest maximum viscosity , setback value and breakdown value. Yongjubyeo had the lowest water solubility index (WSI). The Suweon232 rice variety absorbed more water than any other varieties but rice varieties and amylose contents affected water absorption a little.

• Macromolecular Research
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• v.17 no.1
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• pp.8-13
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• 2009

Natural fiber-filled polymer composites have attracted great interest due to increasing environmental concerns and their low costs. In this study, the properties of rice husk flour-filled polypropylene (PP) were analysed in view of the large quantities of this agricultural product available as residue in Brazil. The rice husk flour (RHF) was characterized by SEM and particle size distribution. The properties of the composites were studied by MFI, DMA, DSC and TGA analyses. A commercial PP modified with maleic anhydride (MAPP) was used as coupling agent. It was verified that RHF decreased the MFI of the composites and that the coupling agent decreased it even more. The efficiency of MAPP was confirmed by the high storage modulus and high loss factor of the coupled composites.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.799-805
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• 2000

In order to manufacture the high-quality products as well as to promote their consumption, dry noodles were prepared with Korean wheat flour and brown glutinous rice flour with and without aroma and quality characteristics of dry noodles were investigated. The average particle size distributions of aromatic brown glutinous rice flour and brown glutinous rice flour ranged from 12.38 to $15.59\;{\mu}m$, which was different from that of control. As a result of farinograph study, water absorption of dough increased and decreased with increasing amounts of brown glutinous rice flour with and without aroma, respectively. Stability, developing time and elasticity of dough showed a decreasing tendency. When compared with the control, aromatic brown glutinous rice samples produced noodles with a greater degree of lightness and a less intensity of yellowing. Replacement of up to 20% of Korean wheat flour by aromatic brown glutinous rice flour and brown glutinous rice flour in noodle had similar cooked properties such as weight gain, volume and water absorption as compared with the control. From the result of sensory evaluation, composite flours(addition up to 30% aromatic brown glutinous rice flour and up to 20% brown glutinous rice flour) and control were rated with a relatively high quality score for appearance, taste and overall eating quality.