• Food Science and Industry
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• v.52 no.1
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• pp.60-67
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• 2019

Protein is a major nutrient of food and has long been studied for nutritional and utility value. Among them, rice protein is attracting attention because of its hypoallergenic characteristics and nutritional value. Rice proteins are divided into endosperm protein and bran protein depending on their location. The two proteins differ in their nutritional characteristics and applications. The endosperm protein is an insoluble protein and has an advantage of digestion and absorption. Rice bran protein dissolves well in water. Its amino acid value is high enough to be comparable to that of soy protein, and it has strong antioxidant ability. Rice protein is a healthy vegetable protein because of its health and hypoallergenic properties. It has been widely used in children's or patients' food, and recently for muscle supplement and health food. Rice protein is considered to be a very effective and useful material as it has been discovered so far.

• Korean Journal of Agricultural Science
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• v.37 no.1
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• pp.61-68
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• 2010

Rice bran proteins from different cultivars(Youngan, Sindongjin, Suwon 511) were extracted with Xylanase using orthogonal analysis method and their functional properties were investigated. The optimum extraction conditions, based on protein content in the extract found to be at 1 wt% xylanase, pH 7 and 50:1, solvent to rice bran ratio(v/w %). Nitrogen solubility indices(NSI) of rice bran protein concentrates were shown a minimum value at pH 4 ranged 2~23%, varied with different cultivars and a maximum (NSI${\geq}$90% for all cultivars) at pH 10. As for water adsorption and fat adsorption capacity, rice bran protein concentrates were shown to be better than Na-caseinate and isolated soy protein, respectively. Emulsifying activities were observed high in order of Na-caseinate>Youngan rice bran protein>Shindongjin rice bran protein>Suwon 511 rice bran protein>isolated soy protein. In general, the surface tension of rice bran protein solution($10^{-3}$ wt%, 5 mM bis-tris, pH 7) was increased with increasing concentrations and found a minimum value near pI. On heating, it was decreased slightly with increasing temperatures up to $70^{\circ}C$ and then increased above $80^{\circ}C$. Addition of sodium chloride was made the surface tension decrease. In conclusion, with Xylanase, rice bran protein concentrate can be successfully extracted from the rice bran of different cultivars and the Youngan rice bran protein was thought to have best functionality among rice cultivars tested. It might be used as a milk protein substitute.

• Applied Biological Chemistry
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• v.20 no.1
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• pp.156-170
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• 1977

Some of the recent developments and studies in the area of rice protein are reviewed. Protein content and amino acid composition of rice are briefly described. Emphasis is given to characterization of rice protein fractions, effects of protein content on grain properties and lysine content of rice, occurence of protein in rice grain and biosynthesis of protein during grain development.

• Journal of Nutrition and Health
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• v.19 no.1
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• pp.16-22
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• 1986

This study was designed to investigate the nutritional effect of mugowrt powder supple mentation to rice diets with different protein levels. Thirty female albino rats weighing 39-43g were adopted for the feeding trial for 4 weeks. The different 5 kind of experimental diets were performed . Control diet was commercially available forage for rats, experimental diet (I-C) highly milled rice, (Ⅰ) highly milled rice 95% and mugwort powder 5%, (Ⅱ-C)highly milled rice 95% and milk casein 5%, and (Ⅱ) highly milled rice 90%, milk casein 5 % and mugwort powder 5%. Growth rate was remarkably high in the dietary group fed on highly milled rice supplemented with 5% mugwort powder (protein 8%) (P<0.05), but it showed the tendency to be rather low in the group fed on highly milled rice supplemented with 5% casein and 5% mugwort powder (protein 12%). Food efficiency as well as protein efficiency appeared similar to the growth rate. Hematodcrit level demonstrated the same tendency as growth rate, but hemoglobin content was observed to increase by diets supplemented with increasing amount of mugwort regardless of protein level. Each nutrient intake was increased by adding mugwort powder to diets after a week's feeding, but it was increased by 8% protein diet, and decreased by 12% protein diet in 3 weeks as well as 4 weeks after feeding . The absorption rate of carbohydrate and protein decreased by feeding mugwort supplemented diets regardless of protein level and feeding period, and that of lipid increased with 12% protein diet.

• Journal of Biosystems Engineering
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• v.23 no.3
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• pp.253-258
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• 1998

The part I was for developing regression models to predict the moisture content, protein content and viscosity of brown and milled rice using Near Infrared(NIR) Reflectance analyzer. The purpose of this study(part II) is to measure fundamental data required for the prediction of rice quality, and to develop regression models to predict the protein content of brown and milled rice, brown rice yield from undried paddy powder by using Near Infrared(NIR) Reflectance analyzer. The results of this study were summarized as follows : The predicted values of protein contents obtained from the undried paddy powder were well correlated to the measured values from brown and milled rice. The predicted yields of brown rice from undried paddy powder were not well correlated to the lab measured values from dried paddy. Continuous study in wavelength selection and of constituent relationship is necessary for practical application.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1998.06b
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• pp.171-177
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• 1998

The part Ⅰ was for developing regression models to predict the moisture content, protein content and viscosity of brown and milled rice using Near Unfrared (NIR) Reflectance analyzer. The purpose of this study(part Ⅱ) is to measure fundamental data required for the prediction of rice quality , and to develop regression models to predict the protein content of brown and milled rice, brown rice yield from undreid paddy powder by using Near Infrared (NIR) Reflectance analyzer. The results of this study were summarized as follows . The predicted values of protein contents obtained from the undried paddy powder were will correlated to the measured values from brown and milled rice. The predicted yields of brown rice from undried paddy powder were not well correlated to be lab measured values from dried paddy. Continuous study in wavelength selection and of constituent relationship is necessary for practical application.

• Journal of Applied Biological Chemistry
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• v.42 no.4
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• pp.180-185
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• 1999

Protein concentrate was produced and succinylated from rice bran to assess and improve its functional properties for the purpose of expanding the uses of rice bran proteins. The most effective solvent for the extraction of rice bran proteins was 20% aqueous ethanol at pH 9. The protein content of rice bran protein concentrate produced was 70.0% and the total protein yield was 64.3%. The extent of succinylation of free amino groups in the modified products was 72.8%. Though the modified protein products showed good functional properties including solubility, emulsion properties, and oil absorption capacity, it did not form gel. Succinylation improved solubility and emulsion and gelling properties. These improvements in functionality will enhance the value of rice bran proteins, thus enabling them to be more competitive with other food proteins.

• Korean journal of food and cookery science
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• v.20 no.4
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• pp.396-402
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• 2004

The aim of this study was to examine the effect of rice protein on the network structure of the Jeung-Pyun. The major component of Jeung-Pyun rice protein was extracted, the change of rice protein during the Jeung-Pyun fermentation was assessed, and the effect on the viscosity and volume of adding protease to Jeung-Pyun was investigated. In addition, the result of adding protein to rice starch on the viscosity and volume of Jeung-Pyun was that the rice protein mediated the volume and expansion ability. The results were as follows. In rice and dough of Jeung-Pyun, the SDS soluble protein content was higher than that of wheat flour and no change was detected in the amount of extracted protein with the fermentation time. However, in the FPLC pattern, low molecular weight peaks were decreased with the fermentation time, which indicates the increase in the ratio of high molecular weight substances. In contrast, the addition of protease substantially decreased, the viscosity and volume of Jeung-Pyun, whereas the viscosity and volume were increased by adding protein to rice starch in order to reconstitute Jeung-Pyun. This suggested that rice protein in Jeung-Pyun had a mediating effect on both the volume and the formation of the texture.

• Preventive Nutrition and Food Science
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• v.18 no.3
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• pp.210-213
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• 2013

The aim of this study was to investigate the effects of isolated protein from white rice on lipid metabolism in a hypercholesterolemic animal model. Male Sprague-Dawley rats were divided into three groups and fed either a normal diet or a high-cholesterol diet (HCD) containing either casein or isolated rice protein for 4 weeks. Compared with rats fed a HCD with casein, the total cholesterol (TC) level in the plasma was significantly reduced in the rats fed rice protein. However, no significant differences were observed in the triglycerides, high-density lipoprotein (HDL), and glucose levels among the experimental groups. Hepatic total lipids and TC levels were significantly decreased by supplementation with rice protein. In addition, rice protein significantly increased the levels of TC and bile acids in the feces. These results suggest that rice protein may improve HCD-induced hypercholesterolemia by enhancing fecal excretion of cholesterol.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.1
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• pp.14-25
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• 2006

Response of grain yield and milled-rice protein content to nitrogen (N) rates at various growth stages is critical for quantifying real-time and real-amount of applied N requirement for target grain yield and protein content. An experiment including 10 N rate treatments at transplanting, tillering and panicle initiation stages with four rice cultivars in 2003, 6 N treatments with two rice cultivars in 2004 and 2005 was conducted. Increase of N rates at PIS significantly increased both grain yield and milled-rice protein content but increase of N rates at tillering stage significantly increased grain yield but not milledrice protein content. Therefore, high grain yield and low milled-rice protein content would be difficult to obtain only by adjusting N rates at PIS. Internal N use efficiency (INUE) was 60.5 kg grain/kg N accumulation on an average over N treatments, cultivars, and experimental years, showing considerable reduction especially at high shoot N accumulation in the experimental year of low sunshine duration. Milled-rice protein content tended to increase almost linearly with increasing shoot N accumulation, but it revealed big variation even at the same shoot N accumulation at harvest. Milled-rice protein content decreased with increasing INUE. N accumulation in the milled rice increased at an almost constant proportion of 45.5 percent of the shoot N accumulated at harvest, showing slight decresing proportion with the increasing shoot N accumulation.