• Journal of the Korean Ceramic Society
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• v.49 no.6
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• pp.535-541
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• 2012

ALC was fabricated using cement, lime, quartzite and a foaming agent via a hydrothermal reaction. ALC has various hydrothermal reaction products and many pores. The properties and colors of ALC surfaces were changed by various factors during ALC fabrication process. This study tested various staying times to analyze these phenomena. It was found that the staying time of green body influenced the properties of hydrothermal products and color of ALC surface. The longer staying time of green body, the lower tobermorite content and cumulative loss weight. An increase in holding time changed color and decreased whiteness of ALC surface. The relationship between whiteness and cumulative loss weight was very high (Coefficient, r = 0.95). It was surmised that tobermorite content was an important factor for enhancement of whiteness However, ettringite and quartzite did not contribute to whiteness.

• Journal of Mechanical Science and Technology
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• v.20 no.6
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• pp.819-827
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• 2006

The stress-strain relation of aluminum (Al) alloy foam cell wall was evaluated by the instrumented sharp indentation method. The indentation in a few micron ranges was performed on the cell wall of Al-alloy foam having a composition or Al-3wt.%Si-2wt.%Cu-2wt.%Mg as well as its precursor (material prior to foaming). To extract the stress-stram relation in terms of yield stress ${\sigma}_y$, strain hardening exponent n and elastic modulus E, the closed-form dimensionless relationships between load-indentation depth curve and elasto-plastic property were used. The tensile properties of precursor material of Al-alloy foam were also measured independently by uni-axial tensile test. In order to verify the validity of the extracted stress-strain relation, it was compared with the results of tensile test and finite element (FE) analysis. A modified cubic-spherical lattice model was proposed to analyze the compressive behavior of the Al-alloy foam. The material parameters extracted by the instrumented nanoindentation method allowed the model to predict the compressive behavior of the Al-alloy foam accurately.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.405-411
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• 1988

In this study, the treatment of $H_2O_2$, papain and acylation on the protein isolate obtained from defatted sesame oil cake for the changes in amino acids composition, color, digestibility and some functional characteristics of this protein were investigated. The results showed that $H_2O_2$, papain and papain $H_2O_2$ treatment increased the rates of the protein extraction and content of protein in protein isolates when those values were compared to the alkali treatment. Also amino acid composition of the protein isolates were comparatively good, and color, and functional properties and pepsin digestibility were markedly improved. The amount of lysine, the first limiting amino acid of this protein was increased. The solubility, bulk density, water absorption, fat absorption and emulsifying properties were remarkably improved while foaming properties and digestibility was slighly decreased.

• Applied Biological Chemistry
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• v.42 no.2
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• pp.128-133
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• 1999

To enhance functional properties of 4 different hoki frame protein hydrolysates (30K, 10K, 5K and 1K hydrolysate) fractionated through a series of 30, 10, 5 and 1 kDa molecular weight cut-off membranes in order to decrease pore size, all hydrolysates were phosphorylated with sodium trimetaphosphate and altered phosphorylated 30K, 10K, 5K and 1K (P-30K, P-10K, P-5K and P-1K), respectively. The covalent attachment of anionic phosphate groups to polypeptide chains improved the functional properties, such as solubility, emulsifying properties and foaming properties, of hoki frame protein hydrolysates. Especially, P-30K hydrolysate with the highest molecular weight fraction possessed the most excellent functional properties among 4 different phosphorylated hydrolysates.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.708-715
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• 1995

Effect of enzymatic modification with pepsin, papain and trypsin was studied on functional properties of isolated sesame meal protein hydrolysates. Solubility of protein hydrolysates distinctively increased from 2% to $53{\sim}94%$ at pH 4. Emulsifying properties showed marked increase 6 fold and 4.5 fold at degree of 10%, 20% hydrolysis by trypsin and degree of 10% hydrolysis by papain. The emulsion stability of the protein was unstable by heat treatment for 30 min. at $80^{\circ}C$. Foaming properties were also enhanced by enzymatic hydrolysis except at degree of 30% hydrolysis. Bulk density and water absorption of protein with trypsin and papain decreased about 0.1 g/ml and $0.3{\sim}0.7\;ml/g$, but oil absorption was increased about 1 ml/g.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.6
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• pp.551-558
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• 1991

We investigated the physicochemical and functinal properties of rapeseed(Brassica napus var. Youngsan) protein prepared by combining various soluvent and purification procedures, such as ultrafiltration (UF) concentration and acid-washin. The lightness value(YCIE) of each protein was greadully improved and its hydrophobicity increased by the degree of purification. The analysis of each protein by sodium dodecyl sulfate-plyacrylamide gel electrophoresis (SDS-PAGE) had nine bands revealed without difference, the considerable portion of which were of $1.96~1.59{\times}10^4$ dalton molecular weight. The content of amino acid increased a little more in the other processed proteins than in the control, and decreased considerably in the proteins extracted by the mixed solvent of 1% sodium hexametaphosphate(SHMP) and 0.25M ethlene diamine tetraacetic acid (EDTA). The better proteins were purified, the lower the kinematic viscosities were in their values. The water absorption and foaming properties were scarcely different according to the processes. The oil absorption and the emulsion activity index normally increased according to the degree of purification. The properties of heat coagulation revealed high values only in the proteins processed by EDTA while they showed considerably low values the other proteins.

• Korean Journal of Food Science and Technology
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• v.17 no.5
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• pp.383-388
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• 1985

Soy protein isolate was acylated with succinic anhydride and acetic anhydride. The functional properties are markedly improved by acylation of the $\varepsilon$-amino groups. Acylation of the available amino groups shifted the isoelectric point from 4.5 to 4.0 and enhanced the solubility between pH 4.0-6.0. In the 0.03M-$CaCl_2$ solution the solubility of the modified soy protein is much larger than that of the unmodified protein above the isoelectric point. The emulsion properties and foaming properties also improved by the modification and the effects of pH on the properties paralleled its effect on protein solubility. The changes of reduced viscosity with concentration followed Huggin's equation and by modification the intrinsic viscosity of the soy protein increased and the interaction coefficient decreased.

• Food Science of Animal Resources
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• v.42 no.3
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• pp.372-388
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• 2022

Insects have long been consumed by humans as a supplemental protein source, and interest in entomophagy has rapidly increased in recent years as a potential sustainable resource in the face of environmental challenges and global food shortages. However, food neophobia inhibits the widespread consumption of edible insects, despite their high nutritional and functional value. The own characteristics of edible insect protein such as foaming properties, emulsifying properties, gelling properties and essential amino acid ratio can be improved by drying, defatting, and extraction. Although nutritional value of some protein-enriched bread, pasta, and meat products, especially essential amino acid components was increased, replacement of conventional food with edible insects as a novel food source has been hindered owing to the poor cross-linking properties of edible insect protein. This deterioration in physicochemical properties may further limit the applicability of edible insects as food. Therefore, strategies must be developed to improve the quality of edible insect enriched food with physical, chemical, and biological methods. It was presented that an overview of the recent advancements in these approaches and highlight the challenges and prospects for this field. Applying these strategies to develop insect food in a more familiar form can help to make insect-enriched foods more appealing to consumers, facilitating their widespread consumption as a sustainable and nutritious protein source.

• Journal of Ocean Engineering and Technology
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• v.36 no.4
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• pp.217-231
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• 2022

Reinforced polyurethane foam (R-PUF), a material for liquefied natural gas cargo containment systems, is expected to have different mechanical properties depending on its stacking position of foaming as the glass fiber reinforcement of R-PUF sinks inside R-PUF under the influence of gravity. In addition, since R-PUF is not a homogeneous material, it is also expected that the coordinate direction within this material has a great correlation with the mechanical properties. So, this study was conducted to confirm this correlation with the one between the mechanical properties and the stacking position. In particular, in this study, R-PUF of 3 different densities (130, 170, and 210 kg/m³) was used, and tensile, compression, and shear tests of this material were performed under 5 temperatures. As a result of the tests, it was confirmed that the strength and modulus of elasticity of the material increased as the temperature decreased. Specifically, the strength and modulus of elasticity in the Z direction, which was the lamination direction, tended to be lower than those in the other directions. Finally, the strength and elastic modulus of different specimens of the material found at the bottom of their lamination compared to the specimens with these properties found at positions other than their lamination bottom were evaluated. Further analysis confirmed that as the temperature decreased, hardening of R-PUF occurred, indicating that the strength and modulus of elasticity increased. On the other hand, as the density of R-PUF increased, a sharp increase in strength and elastic modulus of R-PUF was observed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.4
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• pp.312-319
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• 1988

The functional properties of plasteins have been compared with those of sardine protein concentrate and egg albumin. The solubility of plasteins was higher than that of FPG and the glu-plastein had 84% solubility in the range of pH 3-10. The dispersibility of plasteins was lower than that of egg albumin, however those of plasteins was higher than that of sardine protein concentrate. The water holding capacity of plasteins was higher than that of egg albumin. Lipid absorption of leu-papain plastein was the highest, holding 2.2m119, and that of the other plastein was higher than that of egg albumin. The emulsifying activity of leu-papain plastein was the highest, holding 66.4%, and that of glu-papain plastein was the lowest, holding 51.2%, The emulsifying stability of plasteins was similar to that of the emulsifying activity. The foaming capacitt of leu-papain plastein was the highest, holding 460%, and those of the other plasteins was higher than that of egg albumin. The foaming stability of plasteins was superior to that of egg albumin. The viscosity of plasteins was lower than that of see albumin. The in vitro digestibility of plasteins was 67.6-78.0% range. The digestibility by four pretense were somewhat lower in the glu-papain plastein than in the FPG. The digest of plasteins treated with the microbiol pretense such as molsin and pretense(from Streptomyces griceus), which had a storage broth taste.