• Polymer(Korea)
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• v.36 no.5
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• pp.573-578
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• 2012

In general, most physical properties of wood/polyvinyl chloride (PVC) composites are lower than those of corresponding neat PVC resin because of poor interfacial adhesion between the hydrophilic wood flour and hydrophobic PVC. Therefore, in this study, we treated wood flour with three aminosilanes to improve wood/PVC interfacial adhesion strength, and eco-friendly wood/PVC/nanoclay composites were prepared by melt blending the aminosilane-treated wood flour, a heavy metal free PVC compound, and a type of nanoclay. The effects of treating wood flour with the aminosilanes and adding the nanoclay on the mechanical properties of the composites were investigated. Mechanical properties of the composites were investigated by universal testing machine (UTM), izod impact tester, dynamic mechanical analyzer (DMA), and thermomechanical analyzer (TMA). The tensile properties of the composites with the aminosilane-treated wood flour were considerably higher than those of the composites with neat wood flour. Furthermore, a small amount of the nanoclay improved mechanical properties of the composites. The performance of the wood/PVC composites was considerably improved by using the aminosilane-treated wood flour and the nanoclay.

• Korean journal of food and cookery science
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• v.15 no.3
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• pp.238-243
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• 1999

For the development of technique for isolation of naked barley starch from Youngsan variety, optimum conditions of the isolation process were investigated. The effect of blending was examined and the results showed that 29.7% starch yield was obtained by 6 times of blending. After the blending, the barley starch contained 3.2% protein, 0.7% fat, 0.4% fiber, 0.4% ash and 2.8% ${eta}$-glucan. The opitmum conditions of ${eta}$-glucanase treatment were studied and the results showed that the amount of ${eta}$-glucanase and barley flour-water ratio were 60,000 unit and 1/2, the optimum steeping temperature, pH were $45^{\circ}C$ and 6.5, respectively. The effect of alkali treatment which would be supposed to increase the yield and purity of the barley starch was also examined. 76.7% starch content was obtained by 2 hr of alkali treatment. After all the treatment of isolation process, the barley starch finally contained 0.2% protein and 0.1% ${eta}$-glucan.

• Journal of Nutrition and Health
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• v.15 no.3
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• pp.202-211
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• 1982

A modification of a microbiological assay of vitamin $B_{12}$ was made and used to determine the vita­min levels during kimchi fermentation. A cyanide-buffer solution of pH 6.0 replaced the metabisufite-buffer specified in the A.O.A.C. method. The vitamin $B_{12}$ activity was decreased by blending kimchi samples for 5 minutes and retained the activity by steaming for 10 minutes before blending. The alkali hydrolysis of kimchi at pH 12.0 for 30 minutes at $121^{\circ}C$ was sufficient to destroy the vitamin $B_{12}$ and permit the detection of analogs with the same assay organism. Vitamin $B_{12}$ reached a maximum of 47ng/100g during the fermentation of kimchi ${15}\;4^{\circ}C.$ Inoculation of the kimchi with Propionibacterium shermanii (ATCC 13673) increased the vitamin production to a maximum of 102ng/100g at 1 week of fermentation. Soy flour (0.5%) or beef extract (0.05%), which were regarded as protein sources, added to the inoculated kimchi further increased the vitamin $B_{12}$ activity to 197 and 203ng/100g.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.296-296
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• 2022

This study was investigated to compare the milling and physicochemical characteristics of six Korean wheat cultivars (Keumkang, KK; Jokyung, JK; Goso, GS; Joongmo2008, JM; Baekkang, BK; Saekeumkang, SKK) and five foreign wheat classes (Australian standard white wheat, ASW; Australian hard, AH; US northern spring, NS; US hard red winter, HRW; Soft wheat, SW). Korea and foreign wheat grains were milled using a Buhler MLU-202. Flour moisture, ash, protein, gluten, sedimentation, particle size, solvent retention capacity (SRC) and dough properties of flour were analyzed. Results showed that the hard wheats had a greater total flour yield and reduction fraction yield than the soft wheats regardless of the country. However, there were in the milling characteristics between the US and Korean soft wheats. GS, a soft wheat in Korea, had the lowest flour yield (59.6%) and the highest bran fraction yield (21.4%). The particle sizes of flour by milling fraction were B1>B2>B3 for the largest, and the R1〈R2〈R3 for the smallest. Particle size, ash, protein contents and the values of lactic acid SRC showed highly correlated with flour yield. The gluten-performance-index (GPI) is the ratio of the lactic acid SRC value to the sum of sodium carbonate and sucrose SRC values, and it has been used as a quality indicator for overall performance potential of flour. GPI values differed depending on the wheat variety or class, JM (0.82) was the highest value, and SKK (0.56) and SW (0.59) were low. The curve pattern of the Mixolab result also gives a quality indication of the flour sample. JM and NS flour had similar pattern at water absorption and gluten strength parameters and BK and HRW had similar viscosity patterns. These results will enable further study for blending Korean wheat cultivar to improve the flour quality.

• Polymer(Korea)
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• v.35 no.2
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• pp.124-129
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• 2011

Wood plastic composites (WPCs) are attracting a lot of interest recently. In this study, wood flour/polyethylene (PE) composites panels comprised of a coupling agent and nanoclay were prepared by melt-blending followed by compression molding. Five maleic anhydride grafted polyethylene (MAPE) coupling agents were tested, and the best choice and its optimum content were determined. The mechanical properties of the WPCs were measured by UTM, and the thermal properties were measured by TGA, DMA, DSC, and TMA. Adding just a small amount (1 phr) of organoclay made the tensile and flexural strength and the crystallinity of the WPC somewhat increase and the storage modulus and dimensional stability of the WPC largely increase. SEM images showed that the coupling agent drastically improved wood flour/PE interfacial bonding. Selecting the best coupling agent optimized content and adding a small amount of organoclay resulted in a high performance wood flour/PE composite.

• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.521-527
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• 1989

This study was conducted to investigate the differneces in milling, physicochemical, rheological and end-product properties between Korean and American wheat cultivars. Also, rheological and bread baking properties of Korean wheat flour in blends with U.S. standard flour were investigated. The milling yield of Korean wheat rated 71.1% similar to 71.6% of U.S. wheat. The average AWRC 61.8% of the three Korean wheats ranked higher than the conventional value of 60% for classifying hard and soft wheat. The cookies made from Korean wheat flour showed comparatively good spread with diameter of 8.5-8.9 cm, and marked recommendable top grain score. The volume ranges 975-1175 cc of sponge cake made from all cultivars tested were lower about 4-26% than that of standard cake flour. especially, Wonkwang was selected as one which has special characteristics good for cookie and sponge cake. The volumes of breads from Korean wheat 리ours ranged 924-1020 cc, and Yongkwang of 1020cc marked the most appropriate characteristics for bread-making among the tested wheats. The proper blending ratio of Korean wheat flour to U.S. bread standard flour was revealed 30% in bread-making.

• Korean Journal of Agricultural Science
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• v.48 no.3
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• pp.535-544
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• 2021

When baking, the proper blending or mixing of materials will affect the quality of the product. The mixing strength is important when establishing the optimal conditions for batter, and control of the mixing condition is accordingly an important factor. This study investigated the effects of the mixing speed and time on the quality characteristics of a gluten-free type of rice batter. The batter samples manufactured for this purpose are as follows: control (+) (wheat flour), control (-) (rice flour), T1 (1,800 rpm, 1 min), T2 (1,800 rpm, 2 min), T3 (1,800 rpm, 3 min), T4 (3,600 rpm, 1 min), T5 (3,600 rpm, 2 min), T6 (3,600 rpm, 3 min). In this study, rice flour was used in the T1 to T6 samples. The pH of the batter tended to be higher when the mixing speed was slower and the time was shorter depending on the ultra-high mixing conditions. The moisture content of T3 was highest, and there was no difference according to the ultra-high speed conditions. The specific volumes of the ultra-high mixing treatments were higher than those of the control samples. The relationship between the specific volume, hardness and springiness of rice bread according to the mixing speed and time was weak. Therefore, it is considered that the application of ultra-high speeds when manufacturing gluten-free batter can have a positive effect on improving the production efficiency by reducing the processing time.

• Korean journal of food and cookery science
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• v.21 no.6 s.90
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• pp.927-935
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• 2005

The objectives of this study were to investigate the soaking properties of the high-dietary fiber rice 'Goami 2'and to develop korean white Gruel prepared with Goami 2. With increasing soaking time at room temperature ($20^{\circ}C$), the water absorbing character of Goami 2 and Ilpum significantly increased during the first hour of soaking time, after which it remained constant. On the contrary, the hardness of Goami 2 and Ilpum significantly decreased with increasing soaking time until one hour, after which it remained constant. The properties of Korean white gruel were evaluated using two varieties of rice (Goami 2, Ilpum) and three blending times (10, 20 and 30 seconds respectively). The rice flour of Goami 2 for Korean white gruel showed a greater number of small particles (<20 $\mu$m) than that of Ilpum. Hunter a'and b'values of Korean white gruel prepared with Goami 2 were higher than that of Korean white gruel prepared with Ilpum. The consistency values on Bostwick consistometer of Korean white gruel prepared with Goami 2 were higher than those of Korean white gruel prepared with Ilpum. The texture of Korean white gruel was examined using a back extrusion rig. All of the rheological parameters of Korean white gruel prepared with Goami 2 were decreased with increasing blending time, while in llpum they were increased. In the sensory evaluation results, the overall acceptability of korean white gruel prepared with Goami 2 blended for 20sec showed the highest sensory scores and desirability.

• Culinary science and hospitality research
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• v.7 no.3
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• pp.263-273
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• 2001

This study was to investigate the effect of 5~20% soybean flout(SBF) and/or 0.5~5% calcium on the quality of bread. pH of bread was increased with increasing an amount of SBF and calcium. pH of bread was higher than that of dough. The scores of specific volume and sensory evaluation for the bread quality were shown higher and increased its relative volume in the group of added both of 5~15%, SBF and 0.5~2%, calcium Endothermic peak for a thermal property of bread was increased with increasing the storage time of bread. The bread staling was progressed rapidly in control and calcium added groups only. with increasing an amount of SBF, L values of bread was decreased, but a and b values were increased. However, L, a and b values were shown no difference in the group of calcium added only. Therefore, the optimum blending ratios of SBF and calcium for the quality of bread were 5~10%, SBF and 0.5~1% calcium, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1108-1114
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• 2001

This study was conducted to develop semi-solid infant foods using pumpkins. Purees were made from pumpkin and sweet-pumpkin, and were manufactured with blending, steaming or blanching. The moisture content of sweet-pumpkin puree was lower than pumpkin puree, but viscosity, Hunter\`s L, a, b values, $\beta$-carotene and riboflavin contents were higher. Steaming puree from sweet-pumpkin had the highest score in overall-preference and was selected as the ingredient far infant foods. In amylogram, gelatinization temperature was decreased and amylograph viscosity was increased, as the content of modified starch became high. Semi-solid infant floods were prepared with steaming puree from sweet-pumpkin, modified corn starch, rice powder and dairy products such as milk, whole milk powder and skim milk powder. After sterilization of infant foods, Hunter\`s color values were little changed. And the viscosity of infant foods were increased generally, but kept in 3% modified starch group. Sensory evaluation results showed that sweet-pumpkin puree 40%, rice flour 7%, skim milk powder 3% and water 50% was optimum ratio of infant foods.