• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.597-602
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• 1992

To improve utilization of boxthorn (Lycii Fructus), the boxthron and mixed boxthron (Lycii Fructus, Schizandrae Fructus, Corni Fructus, Zizyphi Fructus, Zingiberis Rhizoma, Cinnamami Cortex) hot-water extractable concentrates were prepared by vaccum evaporation and its rheological properties were investigated. The rheological properties of concentrates $(20{\sim}50^{\circ}Bx)$ followed power low model and showed a pseudoplastic behavior at the temperature range of $20{\sim}60^{\circ}C$. The apparent viscosity of $20^{\circ}Bx$, $30^{\circ}Bx$, $40^{\circ}Bx$ and $50^{\circ}Bx$ boxthron hot-water extractable concentrate was 0.0074 Pa s, 0.0175 Pa s, 0.0431 Pa s and 0.0988 Pa s, that of mixed boxthorn hot-water extractable concentrate was 0.0099 Pa s, 0.0328 Pa s, 0.0720 Pa s and 0.1940 Pa s at $20^{\circ}C$ and 1500 l/s, respectively. The yield stress of boxthron and mixed boxthron hot-water extractable concentrates ranged from 0.045 to 6.253 Pa and from 0.022 to 8.891 Pa, respectively. The activation energy for the flow of boxthron and mixed boxthorn hot-water extractable concentrates increased from 1.6182 to $2.0543{\times}10^7\;J/kg{\cdot}mol$ and from 1.7057 to $2.1462{\times}10^7\;J/kg{\cdot}mol$ with the concentrations of concentrates, respectively.

• Korean Journal of Food Science and Technology
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• v.19 no.2
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• pp.81-88
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• 1987

Rheological properties of rehydrated suspensions of two kinds of freeze dried Kochujang powders, processed at different freezing rates, were compared with raw Kochujang using Brookfield wide-gap rotational viscometer at $25^{\circ}C-60^{\circ}C$. Shear rates ranged from $0.1965\;sec^{-1}$ to $1.9650\;sec^{-1}$ and solid content ranged from 47% to 56%. Rehydrated suspensions of quickly frozen Kochujang powder and slowly frozen Kochujang powder, and raw Kochujang exhibited pseudoplastic behaviors with yield stress and presented thixotropic properties which followed the second-order kinetic behavior proposed by Tiu. Suspensions of Kochujang powders exhibited considerably higher decaying rates than raw Kochujang. The dependency of the equilibrium structure parameter on the shear rate was weak, and there were no significant differences among the values of structure parameters of three samples. The temperature dependency of the apparent viscosity of Kochujang suspension was fully expressed by Arrhenius equation and activation energies of suspensions of quickly frozen Kochujang powder and slowly frozen Kochujang powder, and raw Kochujang were 2.21, 2.18, and 2.32 Kcal/g.mole respectively. Consistency indices of three samples increased with solid content and decreased with temperature. Flow behavior indices of three samples showed no considerable dependency on the temperature and solid content. There were no significant differences in the rheological properties between two Kochujang powders.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.3
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• pp.382-390
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• 1995

To compare the rice yield and grain quality characteristics between mature(MPF) and reclaimed paddy field(RPF), grain yield and its components, some physicochemical properties of rice grain and palatability of cooked rice were investigated for Dongjinbyeo grown at three different locations of mature and reclaimed paddy field, respectively, in south western part of Korea. Variation of culm length in mature paddy area was larger than that in reclaimed saline area. Panicle number per m$^2$ in RPF was more then that in MPF but grain number per m$^2$, filled grain ratio and 1, 000-grain weight in RPF were lower than those in MPT. Average yield of milled rice in RPF was 12% lower than that in MPF (5.l1t /ha). Daejeon showed the highest yielding among MPF and Yeongam reveald the highest grain production among RPF. RPF rices had slightly higher carbohydrate content and alkali digestibility but lower protein, fat and amylose content compared with MPF rices. RPF rices also exhibited higher mineral contents, Mg/K ratio, peak and hot viscosity compared with MPF rices. RPF rice showed slightly poor apparent grain quality but a little better eating quality of cooked rice compared with MPF rice.

• Korean Journal of Food Science and Technology
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• v.19 no.6
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• pp.499-505
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• 1987

The functional properties of lupin seed protein concentrate (LPC) were examined and compared to those of soybean protein isolate (SPI) and Na-caseinate. LPC-50, of which protein level was 50%, was prepared by a two phase solvent (hexane: alcohol: water= 10:7:3) extraction method. LPC-70 was made from LPC-50 by removing the fractions solubilized by carbohydrate decomposing enzymes. The solubilities of LPC-50 and LPC-70 were similar to that of of SPI but slightly higher at pH 4-5, and less susceptible to the added salt. The apparent viscosity of LPC increased exponentially as the concentration increased over 6% level, and the change was similar to that of Na-caseinate. LPC showed strong pseudoplastic non-Newtonean flow behavior, which was similar to that of SPI The emulsifying capasity of LPC-70 was similar to that of SPI when salt was added. The foaming capacity of LPC was comparable to that of SPI. LPC showed high oil and water absorption capacities, which increased as the protein level was elevated. LPC-70 showed the highest oil absorption capacity of all the samples tested.

• Food Science of Animal Resources
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• v.34 no.3
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• pp.378-386
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• 2014

This study was conducted to determine the effects of red and green glasswort on the physicochemical and textural properties of reduced-salt cooked sausages. The control was formulated with 1.5% NaCl; then, three reduced-salt treatments were prepared, with 0.75% NaCl (RS), 0.75% NaCl+1.0% red glasswort (RSR) and 0.75% NaCl+1.0% green glasswort (RSG), respectively. The addition of glasswort within the added amount of 1% had no influence on the pH value of the reduced-salt cooked sausages, regardless of the glasswort type. In terms of color, RSG treatment conveyed a higher hue angle value than the RSR treatment (p<0.05). Increases in the protein solubility (total and myofibrillar proteins) and apparent viscosity of reduced-salt meat batter that were due to the addition of glasswort were observed; however, there were no differences according to the type of glasswort (p>0.05). Furthermore, the addition of glasswort, regardless of its type, resulted in decreased cooking loss, and increased emulsion stability. As a result, reduced-salt cooked sausages formulated with either red or green glasswort demonstrated similar textural properties to those of the control. In conclusion, the type of glasswort within an added amount of 1% had no influence on the physicochemical and textural properties of reduced-salt cooked sausages, except for the color characteristics. In terms of color alteration by the addition of glasswort, the red glasswort, which in comparison with the green glasswort could minimize the color changes of reduced-salt cooked sausages, might be an effective source for manufacturing meat products.

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.161-165
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• 2001

The dietary fiber was extracted from apple pomace with various concentrations of acidic, alkaline solvents and water in $24.4{\sim}29.3%$ yield. The extractions of water-soluble dietary fiber with acidic(6.85%) and alkaline solvent(6.55%) were more effective than the water extraction(6.0%). The higher extraction yield was obtained with increased concentration of acidic or alkaline solvents. The content of galacturonic acid was higher in the order, 0.01 M HCl(77.5%)>0.05 M HCl(76.8%)>$H_2O(76.1%)$>0.05 M NaOH(73.8%)> 0.01 M NaOH(69.0%) and the extraction with acidic solvent showed the highest pectin yield. The color value increased by extraction with solvent in higher concentration. And at equal concentration, the color value of alkaline extract was higher than that of acidic exctract. There was no relationship between the color value and the extraction yield of dietary fiber. In the investigation on the rheological properties, the shear stress increased in proportion to galacturonic acid contents. While water-soluble dietary fiber extracted with acid and water represented Newtonian rheological properties, the alkaline extract was inclined to have converting property from pseudoplastic to Bingham pseudoplastic with increment of alkaline concentration. In the studies on the time-dependence of apparent viscosity, the thixotropic property with hysteresis loop was observed in alkaline extract.

• Korean Journal of Agricultural Science
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• v.22 no.1
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• pp.103-109
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• 1995

The model foods were prepared by simulating mositure, protein and starch, and they were heated for 30 mins, at $80^{\circ}C$ and then cooled at $25^{\circ}C$ in water bath. Their rheological properties were investigated by the use of Brookfield wide-gap rotational viscometer at $30{\sim}60^{\circ}C$, and the rotation speed ranged from 0.6 to 6 rpm and solid content ranged from 8% to 11%, the results obtained were as follows. 1. All the model foods ($P_1S_3$, $P_2S_2$, $P_1S_1$, $P_2S_1$, $P_3S_1$, $P_4S_0$) exhibited pseudoplastic behaviors with yeild stress and were thixotropic foods which showed time - dependent structural decays, but the starch food of 8 ~ 11 % solid content did not show the flow behavior. 2. The correlation between the rheological parameters and the protein content of model foods in various moisture content did not appeared a constant relationship. 3. The change of shear stress against shear rate in high starch foods was larger than that in high protein foods and the structure at initial shear time was decayed with a quatic equation according to the Tiu's Model and structural decay was in parallel with the increase of shear rate. 4. The temperature dependency of the apparent viscosity of $P_1S_2$, and $P_2S_1$ was fully expressed by Arrhenius equation and activation energies of their food were 2.35 and $1.34Kcal/g{\cdot}mol$, respectively.

• Korean Journal of Materials Research
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• v.11 no.6
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• pp.465-471
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• 2001

The effect of sintering condition on the mechanical properties and leachability of polydispersed ceramic core body made by gel-casting process in aqueous medium have been investigated. The polydispersed ceramic slip that has low viscosity($\leq$1000cP, at 1000cP (at $50sec^{-1}$ ) and high solid loading(50vo1%) was obtained. The green bodies were fabricated through casting and gelation at room temperature followed by drying at $25^{\circ}C$for 48hrs under relative humidity of 80%. Crack-free green body was successfully fabricated through the above process. The strength at room temperature, apparent bulk density, and shrinkage of the ceramic core body increased propotionally with increasing sintering temperature(1100~150$0^{\circ}C$). However, porosity of the ceramic core body showed relatively low vague. Leaching rate of sintered core body increased with increasing porosity of the sintered body, and was significantly dependent upon the concentration of alkali caustic solution at the same leaching temperature.

• The Journal of Engineering Research
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• v.5 no.1
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• pp.73-87
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• 2004

The synthesis and crystallization of amorphous calcium carbonate($CaCO_3$.$nH_2 O$) obtained from gas-liquid reaction between aqueous solution of calcium hydroxide and carbon dioxide at 15~$50^{\circ}C$ are investigated by electrical conductometry, XRD and TEM. The results are as follows: The initial reaction products prior to the formation of precipitated calcium carbonate is amorphous calcium carbonate. The electrical conductivity values in the slurry are decreased during the formation of amorphous calcium carbonate which covers particle surface of calcium hydroxide and retard the dissolution of calcium hydroxide into the solution. that amorphous calcium carbonate is unstable in the aqueous solution and crystallizes finally to calcite by the through-solution reaction. While amorphous calcium carbonate crystallizes into chain-like calcite, the conductivity values are recovered rapidly and the apparent viscosity of slurry containing higher concentration of calcium hydroxide increase. At below pH 9.5, chain-like calcite separates into individual particles to form precipitated calcium carbonate. The formation and synthetic temperature range of amorphous calcium carbonate is most suitable a primary decreasing step(a-step) at $15^{\circ}C$ in the electrical conductometry.

• Korean Journal of Poultry Science
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• v.16 no.3
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• pp.157-167
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• 1989

Pretreatment of egg white and ion exchange resins was attempted to separate lysozyme from egg white efficiently. Apparent viscosity of egg white could be decreased to 3cp by homogenization for 30 minutes at 2, 000rpm and ultrasonication for 45 minutes. The result of testing adsorption capacity of lysozyme was as follows； CM-Sephadex C-25 ＞Duolite C464＞Amberlite C-50＞Dowex MSC-1＞Amberlite IRC-50＞Amberlite IRC-84. Although CM-Sephadex C-25 showed highest adsorption capacity of lysozyme, egg white could not eluted easily. Duolite Cf64 was selected based on relatively high lysozyme adsorption and good egg white eluting property for separation of egg white lysozyme. Na$^{＋}$ form of Duolite C-464 was most effective on adsorption of Iysozyme. To separate lysozyme from egg white efficiently rinse buffer and eluting solution were selected 0.1M sodium phosphate buffer at pH 6.5 and 10% ammonium sulfate respectively. After separating lysozyme from egg white, foaming power of egg white was decreased to 85.3%. Color of egg white gel was not changed while hardness of egg white gel was decreased by 30% after separating lysozyme. However, elasticity of egg white gel was increased by 13% in lysozyme-separated egg white.