• Transactions of the Korean hydrogen and new energy society
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• v.18 no.1
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• pp.85-94
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• 2007

Rice straw, produced as an agricultural by-product, is usable biomass as fuels if depolymerized to monomer unit, because the chemical structure are similar to high octane materials found in gasoline. In this study, parameters of thermochemical degradation by solvolysis reaction of rice straw such as the effect of reaction temperature, reaction time and type of solvent on conversion yield and degradation products were investigated. It was found that the effectiveness of the solvent on the solvolysis reaction was as follows; acetone>cresol>butanol. When acetone was used as a solvent, the highest rice straw conversion was observed to be 91.5% at $500^{\circ}C$, 40 min. Combustion heating value of liquid products from thermochemical conversion processes was in the range of 7,380 cal/g. The energy yield and mass yield in acetone-solvolysis of rice straw was as high as 69.0% and 38.2 g-oil/100g-raw material after 40 min of reaction at $350^{\circ}C$. Various aliphatic and aromatic compounds were detected in the rice straw solvolysis products. The major components of the solvolysis products, that could be used as fuel, were 4-methyl-2-pentanone, 3,5,5-trimethyl-2-cyclopentan-1-one as ketones.

• Microbiology and Biotechnology Letters
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• v.27 no.4
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• pp.333-338
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• 1999

This study was aimed to develop a value-added fermented products from rice and apple pomace using Bifidobacterium fermentation. The Bifidobacterium fermentation system of the mixture of rice and apple pomace was developed, and the physicochemical properties of the products were investigated. After 4 different bifidobacteria were compared for their fermentation capability and sensory properties of the fermented product, Bifidobacterium FBD-13 and FBD-22 were selected as appropriate strains for the fermentation of saccharified rice solution(SRS). The optimum inoculation level was 2% and the optimum fermentation time was 42 hrs. When wet apple pomace(WAP) was added to SRS, it contributed to the improvement of sensory properties of the fermented products and the optimum mixing ratio was 40% WAP and 60% SRS in weight. For the fermentation of the mixture of WAP and SRS, Bifidobacterium FBD-27 and FBD-22 were selected as suitable strains.

• Korean journal of food and cookery science
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• v.28 no.6
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• pp.813-820
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• 2012

To develop the high quality gluten-free rice products with health functionality and desirable texture with moistness, the physicochemical properties of extruded rice flours prepared from the mixture of germinated brown and white rices were investigated. The domestic organic Samgwangbyeo was used to make white and germinated brown rices. White rice (WR) was dried after soaked for 6 h at $15{\pm}3^{\circ}C$ and mixed with germinated brown rice (GBR) with different mixing ratios (100:0, 75:25, 50:50, 25:75, 0:100). The operating conditions of twin screw extruder were 250 rpm of screw speed, $120^{\circ}C$ of barrel temperature, and 25% moisture content of rice flour. The ash, crude protein and crude lipid contents were significantly different (p<0.05) and those of extruded GBR were the highest values, but those of extruded WR were the lowest. The color difference of extruded WR based on white plate showed the lowest among them. The water binding capacity (334.16%), swelling power (8.83 g/g), solubility (33.13%), and total starch (79.50%) were the lowest in extruded GBR. The viscosities of all extruded rice flours by RVA were maintained during heating. The peak and total setback viscosities of extruded rice flours ranged 127-352 and 58.0-85.5 cP, respectively. The novel food biomaterial from germinated brown rice as well as white rice was developed by twin screw extruder. The extruded rice flours control the moistness to improve the texture and also have functional materials, dietary fiber, GABA, and ferulic acid, etc to increase quality of gluten free rice products.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.1-6
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• 2006

Rice is the most important crop in Korea and its annual production of 5.2 million ton is followed by over 0.5 million ton of bran as by-products of milling process. Although rice bran contains various nutritious and pharmaceutical compounds, rice brans are rarely utilized as functional food sources in Korea. In recent, tocotrienols are well known having distinctive pharmaceutical effectiveness. So tocotrienols extracted from rice bran oil were evaluated about Pharmaceutical function. The $IC_{50}$ of tocotrienols products against liver cancer, HepG2 cells were $149mg\;mL^{-1}$, indicating anticancer activity of final products. By animal feeding tests, the final products containing tocotrienols did not induce any toxicity signs in mortality, Incidence of clinical signs, body weight, etc. after a single oral administration, which proved safety of the tocotrienol products. In conclusion, tocotrienol extracted from rice bran has pharmaceutical activity without any toxic effects, which is also suggested tocotrienol products may be a good fortifying nutrition far the health and medical care.

• Fisheries and Aquatic Sciences
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• v.17 no.2
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• pp.167-173
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• 2014

Surimi (or fish paste) products are one of the most representative processed seafoods in Korea. In a previous study, we evaluated the potential use of rice flour as an agent to replace wheat flour in surimi products. In this study, we optimized the content of rice flour and water in surimi products using response surface methodology. Rice flour content ($X_1$, w/w) and water content ($X_2$, v/w) were chosen as independent variables and gel strength ($Y_1$) and overall acceptance ($Y_2$) as dependent variables. Optimal conditions of $X_1$ and $X_2$ were 14% and 9.1%, respectively, and the predicted values of the multiple response optimal conditions were $Y_1=656.4(g{\cdot}cm)$ and $Y_2=6.34$. Under optimal conditions, the experimental values of $Y_1$ and $Y_2$ were $647.8(g{\cdot}cm)$ and 6.21, respectively, which were similar to the predicted values. Surimi products that are prepared under optimum conditions were similar in gel strength to those of commercial products. However, its sensory evaluation score was higher than that of the commercial products. In conclusion, rice flour can not only be used as an alternative to wheat flour, but it also can be used to improve the quality of surimi products.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.3
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• pp.395-402
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• 2020

In recent years, the home meal replacement (HMR) market has expanded and the consumption of ready-to-heat (RTH) rice has significantly increased. In this study, RTH rice products containing seaweed were prepared with different types of grain: white rice, a mixture of white rice and barley, barley, and mixed grains. The control was a commercial RTH white rice without seaweed. The proximate components, total dietary fiber, in vitro starch digestibility, and antioxidant activity were compared. The ash content of the RTH seaweed rice was higher than that of the control (P<0.05). The total dietary fiber of the RTH seaweed rice was in the range of 1.03-6.57%, which directly impacted the in vitro starch digestibility. The in vitro antioxidant activity including total phenolic content, reducing power, DPPH (2,2-diphenyl-1-picryl-hydrazyl) and ABTS⁺ (2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid) radical scavenging activity of the seaweed rice with barley and the white rice/barley mixture was greater than that of the other rice products (P<0.05). These results indicate that the in vitro digestibility and antioxidant activity of the HMR RTH seaweed rice were greater than those of the control. In addition, when the RTH seaweed rice was prepared with barley, the functional activity improved.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1026-1032
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• 2001

Microwave treatment was studied to investigate the antioxidant ability of rice hull and rice bran. The color changes were related to the intensity of microwave and to the treated time on rice bran. However, the electron donating abilities of rice hull and rice bran extract were not much affected by microwave intensity. Rice hull extract treated with a 100 W microwave showed 80% inhibition of lipid peroxidation when fish oil was treated with $H_2O$$_2$. Also inhibition activity against lipid peroxidation in rice hull is more stable than that of rice bran when treated with microwave. Overall, rice hull extract showed better antioxidant activity than rice bran. It seems that rice hull contains higher antioxidant components as well as the browning reaction products having anti-oxidant activity during microwave treatment.

• Journal of the Korean Wood Science and Technology
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• v.28 no.3
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• pp.9-13
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• 2000

Wood demand is increasing more and more, but world has been confronted with decreasing forest resources. Korea has to depend upon foreign wood and wood-based products for more than 95 percent of total domestic demand per year. In order to heighten self-sufficiency for wood supply and demand, we have to develop wood substitutes. Rice hull is the cheapest agricultural by-product we can get in Korea, more over the production of rice hull amounts to 1 million tons per year. This study was carried out to utilize rice hull and to decide the optimum condition of rice hull pretreatment for manufacture of rice hull board. Steam explosion method gave the best result, and the next boiling treatment of 1 hour, the last 1 hour treatment with 1% NaOH solution. Optimum conditions of explosion method were 20kgf/$cm^2-1$ minute and 25kgf/$cm^2-1$ minute. Rice hull board made with exploded rice hull met the KS standard(KS F 3104, 1997) and showed the same strength as a control, PB. And also the 1 hour boiling treatment was more effective than the 1 hour treatment with 1% NaOH solution.

• Nutrition Research and Practice
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• v.1 no.1
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• pp.8-13
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• 2007

Cooked rice is a staple food for Koreans which provides more than 60% of daily required energy. In 1960's, Koreans ate 600 g-800 g of cooked rice per meal and the energy obtained from cooked rice was almost more than 80% of the daily intake of energy. However, as the economy of Korea improved, the major industry has been shifted from agriculture to various manufacturing industries and the export of those products has been increased thus increasing the national income but decreasing the farming population and thus rice consumption have been decreased. It has been said that the decreased rice consumption is caused solely by decreased farming population but it can also be said that the decreased farming population is caused by decreased rice consumption. As the national income increases, the type of foods people consume have become diversified. Various processed foods such as convenience food or ready-to-eat food have been widespread, which are mostly made of wheat flour rather than rice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.1
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• pp.54-61
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• 2002

The antioxidant activities of methanol extracts of sixteen samples were tested using 1.1-diphenyl-2-picryl hydrazyl(DPPH) reactivity and TBARS substances assay in vitro. The methanol extracts of the rice brans from three wild rice -O. minuta, O. rufipogon, and O. barthii-were found to be the most effective in DPPH radical scavenging activity. The next effective ones were the rice brans of Heugjinjubyeo and leaves of Tapgolbori. When tested on lipid peroxidation using a lipid peroxidation generation system mediated by $H_2O$$_2$/Fe$^{2+}$ in rat liver homogenates, the brans and hull of wild rice (O. minuta, O. rufipogon, and O. barthii) and rice bran of Heugjinjubyeo exhibited protective activities against lipid peroxidation in the order of effectiveness.s.