• Food Engineering Progress
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• v.15 no.4
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• pp.413-419
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• 2011

For producing a high added-value natural seasoning ingredient, a yeast extract (Yx) was supplemented with a rice protein residue fermented with Bacillus licheniformis (Rfl) or with Bacillus subtilis (Rfs). A rice protein residue was obtained after enzymatic hydrolysis of rice protein which was used for preparing a yeast culture medium. Overall acceptabilities of the supplemented yeast extracts (YxRfl or YxRfs) were higher compared to pure yeast extract. Savory taste like umami was found to increase noticeably by adding a fermented rice protein residue to yeast extract, which was confirmed in taste sensor analysis and in sensory test. Beyond the presence of savory tasting amino acids such as Glu and Asp in a fermented rice protein residue, it is assumed that other soluble peptide fractions remained play an important role in enhancing taste of the supplemented yeast extracts. Thus, the yeast extract added with a fermented rice protein residue could be applied to manufacture a natural seasoning ingredient.

• Journal of the Korean Society of Food Science and Nutrition
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• v.8 no.1
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• pp.21-24
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• 1979

A study was made to investigate the effect of L-lysine fortification on the quality of rice protein by albino rat-feeding trials. Five subjects fed diets providing 1) rice protein only, 2) rice protein+0.25% L-lysin HCI, 3) rice protein+0.5% L-lysin HCI, 4) rice protein+0.75% L-lysin HCI and 5) rice protein+1.0% L-lysin HCI for 28 days respectively. Protein efficiency ratio(PER) indicated that 0.25% lysine fortified diet had highest value. Lower PER values were shown in the higher fortified diets(0.5% through 1.0% L-lysine) comparing to 0.25% fortified diet. However, there was no adverse effect on the protein quality by the given fortificaton level($0{\sim}1.0%$ L-lysin HCI addition).

• Food Engineering Progress
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• v.15 no.3
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• pp.243-249
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• 2011

Optimum conditions to prepare a yeast extract with rice protein hydrolysates(rh) were investigated. The yeast extract was obtained at the level of 2.3 g/L from the yeast culture medium($30^{\circ}C$, 48 hr) composed of 5% rh and glucose( 3%, w/w). Within the extract, RNA was contained at the level of 188.1 mg/g and the levels of GMP and IMP as nucleotides were $650.33{\pm}48{\mu}g/g$, $69{\pm}21{\mu}g/g$, respectively. When Rrh(Residual rice protein hydrolysate by $Delvolase^{(R)}$) was supplemented into a yeast extract, the savory taste like umami of the mixture was found to increase noticeably based on the measurements by taste sensing system as well as sensory test. It is assumed that soluble peptides in Rrh could play an important role in improving the overall taste of yeast extract by enhancing its umami taste. Therefore, the yeast extract supplemented with Rrh could be used for manufacturing a high value-added natural seasoning ingredient.

• Applied Chemistry for Engineering
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• v.31 no.4
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• pp.398-403
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• 2020

In this study, six kinds of rice grown in Cheongwon area were extracted using glycolytic and proteolytic enzymes, and also antioxidant effects and water holding capacity of rice protein extracts were compared and analyzed. Protein contents of rice cultivars protein extract showed that black rice (BR) extract was the highest at 4,900 ㎍/mL, and flavored brown rice (FBR) extract was the lowest at 3,700 ㎍/mL. 2,2-diphenyl-1-picryl-hydrazyl-hydrate free radical scavenging activity was confirmed the superior activity of more than 80.0% at a concentration of 2 mg/mL with BR and red brown rice (RBR) extracts. 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity at a concentration of 2 mg/mL with BR and RBR extracts was more than 70.0% The water holding capacity for extracts using RBR, red-kerneled brown rice (RKBR), BR and FBR was more than 110.0%. Overall, the rice protein extract using BR has excellent antioxidant and water holding capacity which can be used as a potential skin moisturizer and antioxidant functional cosmetic material.

• Proceedings of the Korean Society of Crop Science Conference
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• 2021.10a
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• pp.29-29
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• 2021

• Applied Biological Chemistry
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• v.26 no.1
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• pp.65-72
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• 1983

The composition of four rice protein groups is greatly affected by the extraction conditions. The extraction amounts of albumins and glubulines primarily depended on the temperature rather than the method of extraction. The total amount of glutelins, the major components of rice storage proteins, could be extracted by a successive extraction processes, extraction with 0.5% SDS-0.1M borate buffer(pH 8.3) followed by extraction with 0.5% SDS-0.6% ${\beta}-mercaptoethanol-0.1M$ borate buffer(pH 8.3). The extracted amounts of glutelin with these solvents were 54.1 and 45% respectively. The further purification of SDS soluble glutelins was achieved by Sephadex G-150 gel column chromatography. The molecular weight of the components in four protein groups has been estimated by SDS-polyacrylamide gel electrophoresis with or without ${\beta}-mercaptoethanol.$ The comparison of albumins and globulins by starch gel electrophoresis at pH 3.1 permitted us to identify seven rice varieties. However, at pH 8.95, the specific bands for Japonica type rice varieties were observed.

• Applied Biological Chemistry
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• v.12
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• pp.13-17
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• 1969

The fractions of protein, albumin, globulin, oryzenin, and prolamine extracted from 20 varieties of rice were determined, which include upland and paddy rice with both waxy and nonwaxy types. The protein content is higher in the waxy type and especially in upland rice. The content of oryzenin and albumin were likewise higher in the waxy and upland types. The results were discussed in the view point of nutrition.

• 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 Poultry Science
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• v.37 no.1
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• pp.69-80
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• 2010

Hypocholesterolemic effect of soy protein was examined in comparison with casein and three other dietary protein sources in chicks. In two feeding trials, 40 (Expt.1) or 50 (Expt. 2), three-day-old, male chicks were forced-fed each of five semi-purified-type diets containing isolated soy protein (ISP, cp 82%), casein (cp 92%), rice protein (RP, cp 70%), corn gluten meal (CGM, cp 65%) or fish meal (FM, cp 70%) for two weeks. The diets for Expt. 2 were supplemented with 0.3% cholesterol by replacing glucose. Each protein source was the only source of protein of each diet. Essential amino acids were added to the diets to satisfy their requirements according to NRC. The diets were forced-fed to equalize the intake of all nutrients except the amino acids which were inherently variable in the diets. Chicks fed casein showed lower body weight gain than those fed the other proteins in both experiments. Birds fed ISP and FM gained better body weight than the others. Chicks fed casein showed significantly higher levels of plasma total cholesterol, non-HDL cholesterol and triacylglycerol (TG) than those fed ISP and the other protein sources. Meanwhile, the chicks fed ISP, RP, CGM and FM showed comparable levels of plasma total cholesterol, non-HDL cholesterol and TG. In Expt. 2, the birds fed casein and FM showed markedly elevated plasma total cholesterol and non-HDL cholesterol levels. Liver weight and levels of total lipids and cholesterol of chicks fed casein appeared significantly higher than those of the other protein diets, whereas those of the chicks fed ISP, RP, CGM and FM appeared comparable except cholesterol in FM group. In conclusion, only the chicks fed casein diets in both experiments always showed significantly higher levels of plasma cholesterol and TG compared to those fed ISP and the other protein sources. These results support the views that casein, which has unique lysine-arginine ratio, is inherently hyper-cholesterolemic, and ISP is hypocholesterolemic only when compared to casein.

• 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.