• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.4
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• pp.531-538
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• 2003

To elucidate the physicochemical change of Panicm miliaceum powders caused by irradiation and identify detection of irradiation, viscosity, TBA value, Hunter color and total viable count were measured after irradiation of Panicum miliaceum powder. Panicum miliaceum powders from Korea and China were irradiated at 0, 2.5, 5, 7.5, 10, 15 kGy using a $Co^{60}$ irradiator and stored for 9 months at $0^{\circ}C$ and $20^{\circ}C$. All samples resulted in decrease for viscosity and specific parameter values by increasing dosage at 50 rpm after irradiation. These values showed dose-dependent relationship (above $r^2$＝0.92) between non-irradiated and irradiated samples during storage. These results suggest that the detection of irradiated Panicum miliaceum at various doses is possible by using viscometric method during storage. Total viable count, TBA value and Hunter color were determined as assistant indices for the samples viscosity measured. Total viable count, TBA values showed dose-dependent relationship (2.5 ~15 kGy). The difference in viscosity along with total viable count, TBA values between non-irradiated samples little or some changed with the lapse of post-irradiation time, but was still distinguishable each other more than 6 months at $0^{\circ}C$ and $20^{\circ}C$ for Panicum miliaceum powders from Korea and China.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2001.05a
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• pp.52-57
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• 2001

Laminar two-dimensional time-dependent flow past a circular cylinder is numerically investigated using direct numerical simulation for the low Reynolds number (Re=164∼280). The higher-order finite difference scheme is employed for the spatial distributions along with the second order Adams-Bashforth and the first order backward-Euler time integration. The convection term is applied by the 7th order up wind scheme and the pressure and viscosity terms are applied by the 4th order central difference. The grid system makes use of the regular grid system and it is generated by an equation. The calculated results of drag coefficients, lift coefficients, pressure distributions, and vorticity contours and other information are compared with experimental and numerical ones. These results obtained by the present DNS show good agreement with the previous studies.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.4
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• pp.41-50
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• 2017

The design of proper agitation system is requisite in biological waste treatment and energy generation plant, which is affected by viscosity, impeller types, and power consumption. In the present work, hydrogen fermentation of food waste was conducted at various operational pHs (4.5~6.5) and substrate concentrations (10~50 g Carbo. COD/L), and the viscosity of fermented broth was analyzed. The $H_2$ yield significantly varied from 0.51 to $1.77mol\;H_2/mol\;hexose_{added}$ depending on the pH value, where the highest performance was achieved at pH 5.5. The viscosity gradually dropped with shear rate increase, indicating a shear thinning property. With the disintegration of carbohydrate, the viscosity dropped after fermentation, but it did not change depending on the operational pH. At the same pH level, the $H_2$ yield was not affected much, ranging $1.40{\sim}1.86mol\;H_2/mol\;hexose_{added}$ at 10~50 g Carbo. COD/L. The zero viscosity and infinite viscosity of fermented broth increased with substrate concentrations, from 10.4 to $346.2mPa{\cdot}s$, and from 1.7 to $5.3mPa{\cdot}s$, respectively. There was little difference in the viscosity value of fermented broth at 10 and 20 g Carbo. COD/L. As a result of designing the agitation intensity based on the experimental results, it is expected that the agitation intensity can be reduced during hydrogen fermentation. The initial and final agitation intensity of 30 g Carbo. COD/L in hydrogen fermentation were 26.0 and 10.0 rpm, respectively. As fermentation went on, the viscosity gradually decreased, indicating that the power consumption for agitation of food waste can be reduced.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.4
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• pp.355-363
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• 1999

The experiments were carried out to elucidate the varietal variation of retrogradation in aged cooked rice and its association with some physicochemical properties of milled rice. The fifteen rice materials were selected from forty-three low-amylose japonica and Tongil-type rice cultivars based on palatability and retrogradation of cooked rice stratified by preliminary sensory evaluation of warm and cooled cooked rice. One japonica glutinous rice variety was included for comparison of retrogradation of cooked rice. The $\alpha$-amylase-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The desirable checking time for evaluating the varietal difference in deterioration of aged cooked rice was four hours after storing in room temperature and two hours after preserving in refrigerator based on the largest coefficients of variations in degree of retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were Ilpumbyeo, Chucheongbyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tongil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, showed the relatively fast deterioration of cooked rice. The retrogadation index represented by the percentage of retrogradation difference between warm and cooled cooked rice to original estimates of warm cooked rice was significantly affected by the degree of retrogradation of cooled cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogradation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked nce. The varietal difference in retrogradation of cooked rice can be effectively classified by scatter diagram on the plane of upper two principal components based on some retrogradation properties of cooked rice. The deteriorated structural change in cooled cooked rice by observing through the scanning electron microscope was more conspicuous in the fastly retrograded cooked rice than in the slower one.

• Culinary science and hospitality research
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• v.3
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• pp.367-383
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• 1997

1. It is necessary for all cooks to understand the eggs for making the bakery. It will lead for them to make a difficient and reasonable job. 2. To understand the viscosity, Cooks have the view of the difference between the old eggs and the fresh eggs. 3. The cooks have the ability to apply the baking temperature by the exact understanding of the solidification. 4. The cooks have the basic knowledge to create the whipping items. 5. The cooks have the ability to develop the emulsion items by the exact understanding of the emulsification. 6. The cooks have the creativity to put in practice the bakery by reviewing the representative egg item.

• Journal of the Korean Society of Safety
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• v.13 no.2
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• pp.76-87
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• 1998

This study was carried out to investigate the effect of on temperature control from actuating method, recycling ratio and the position (top, middle and bottom) of set and controlled temperature within the reactor in adiabatic ebullated recycling condition, when the disturbance was occurred. Estimation of the solution were performed numerically using the finite difference method. It was assumed that the reaction is in constant with heat of reaction and the physical properties(density, heat capacity and viscosity, etc) of the reactants are same condition within the reactor.

• Tribology and Lubricants
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• v.10 no.3
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• pp.54-61
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• 1994

The regimes of elastohydrodynamic lubrication at the points where line contacts occur between the vane tip and camring in an oil hydraulic vane pump is studied. A study of the contact conditions in vane pump provided most of the early interest in the possibility of fluid film lubrication in highly loaded contacts. The variation of viscosity with pressure and the elastic deformation associated with the high pressures generated in the contact region are the major causes of the complexity attributed to lubrication behavior. Therefore a numerical solutions to the problem of elastohydrodynamic lubrication of line contact are obtained by using a finite-difference formulation.

• Applied Biological Chemistry
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• v.34 no.1
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• pp.75-76
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• 1991

Bran structure and gelatinization property of upland and lowland japonica waxy brown rice were compared. Dimension, weight and number of aleurone layer were similar between upland(Nonglimna 1) and lowland(Shinsunchalbyeo) rices, but the aleurone layer and pericarp of upland rice were thicker. Water uptake rate of upland rice at $60^{\circ}C$ was lower than that of lowland one. There was no difference in intrinsic viscosity between two rice starches. Upland rice starch had lower onset temperature, narrower gelatinization temperature and lower water content lot gelatinization compared with lowland rice starch.

• Culinary science and hospitality research
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• v.12 no.1 s.28
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• pp.82-92
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• 2006

The purpose of this study was to investigate sensory characteristics of brown sauce made with different ratio of chicken bone. Brown sauces made from chicken bone and beef bone respectively were evaluated by pH, viscosity, turbidity, Hunter's color and sensory evaluation. With chicken bone increased, pH of brown sauce changed from 5.11 to 5.72 (p<0.05) that was lower than optimal bacterial growth condition between 6.8 and 7.0. Viscosity increased with higher chicken bone ratio (p<0.05) and desired viscosity can be obtained by controlling chicken bone content. Turbidity increased with chicken bone (p<0.05), which might be caused by the thick chicken bone extract. Lower Hunter "L" value and higher "a" and "b" value were shown with increase of chicken bone (p<0.05). The sensory evaluation was performed with scoring tests for color, flavor, viscosity and taste by 20 professional panels who were professional cooks working in I hotel. Better scores of color, flavor, taste and overall evaluation except viscosity were observed with increase of cattle bone (p<0.05). There was not a significant difference between chicken bone and beef bone 0.0 : 10.0 and 2.5 : 7.5 (p>0.05). Brown sauce made with 2.5 : 7.5 can be prepared without reducing sensory quality.

• Journal of the Korean Ceramic Society
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• v.39 no.11
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• pp.1090-1096
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• 2002

Six different composition of water-swellable bentonite rheology modifiers(WSB-1~WSB-6) were prepared by the compounding of peptizers and anionic surfactants as an additives with Bentonite(BEN) of montmorillonite group. Average particle size, particle morphology and water-swellability of WSB and the viscosity with additives were measured, respectively. And the rheological behavior of WSB were investigated using the rheometer. The viscosity of WSB-1 increased with decreasing both pH and average particle size of BEN, WSB-2 treated $Na_2CO_3$ as a peptizer showed the maximum viscosity. These results can be interpretated cause for rearrangment as the edge-to-face structure of BEN particles containing WSB. Also, WSB-4∼WSB-6 containing both peptizer and anionic surfactant was sol phase that their viscosity was not nearly with the shear rate, however, WSB-3 containing Tetrasodium Pyrophosphate(TSPP) as an anionic surfactant showed the thixotropy by the viscosity difference of 1000 times with the shear rate. From this result, the anions of TSPP can be explained to arrange in edge of BEN particles containing WSB-3.