• Preventive Nutrition and Food Science
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• v.1 no.2
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• pp.190-195
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• 1996

Texture-modifying and freeze-thaw stabilizing effects of different wheat gluten and modified starches on surimi based-product were evaluated. The different incorporation manners of wheat gluten and modified wheat starch in surimi gel were also examined to evaluate their effects of textural properties on surimi gel. The addition of wheat gluten reduced the gel strength of surimi, but after freeze-thaw cycle it significantly improved freeze-thaw stability by reducing freexe-thaw expressible moisture and also by preventing rubbery texture development, Gluten-1 incorporated surimi gel showed higher functionality in forming cohesive gel determined by compressive and penetration force as wall as expressible moisture after freeze-thaw cycle. Surimi gel containing modified wheat starch showed better freeze-thaw stability that of modified potato starch. When a preblended mixture of wheat gluten and starch are incorporated into surimi gel, it made gel texture significantly softer as so in high sensory score. The compertition for moisture between gluten and starch is a main reason to show different way of textural modification.

• Applied Biological Chemistry
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• v.21 no.2
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• pp.112-118
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• 1978

Xanthine oxidase from bovine thyroid glands was purified to apparent homogeneity when judged by analytical disc gel electrophoresis. The purification procedures include pancreatin digestion, butanol extraction, ammonium sulfate precipitation, calcium phosphate gel adsorption, ultrafiltration, calcium phosphate gel-cellulose column chromatography, gel filtration, preparative Sephadex G-25 column electrophoresis, and preparative polyacrylamide gel electrophoresis. The enzyme was enriched 1,000-fold. However, its specific activity was markedly low as compared with highly purified milk enzyme. Thyroidal xanthine oxidase exhibited a low specificity for substrates and electron acceptors. The kinetic properties of thyroid xanthine oxidase were found to be similar to those of the milk enzyme on the basis of Michaelis constants for common substrates.

• Journal of the Korean Ceramic Society
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• v.34 no.11
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• pp.1187-1197
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• 1997

Dry gel composed of primary particles more homogeneous than starting boehmite powder was prepared by dispersing and gelling the boehmite powder. The transformation temperatures of boehmite powder, dry gel seeded with 0, 1, 3, 5 wt% $\alpha$-Al2O3, and ball milled gel were 1192$^{\circ}C$, 1184$^{\circ}C$, 1141$^{\circ}C$, 1119$^{\circ}C$, 1117$^{\circ}C$, and 1106$^{\circ}C$, respectively. Sintering behavior of dry gel without seed was similar to that of boehmite powder, but the sintered density of dry gel was improved as much as 10%~15% than boehmite powder. In the case of dry gel seeded with 5 wt% $\alpha$-Al2O3, sintering behavior was much improved. The relative density of the gel seeded with 5 wt% $\alpha$-Al2O3 was 96% when sintered at 140$0^{\circ}C$ for 1h. On the other hand, ball milling of the non-seeded sol for 48h resulted in the relative density of 97% when sintered at 130$0^{\circ}C$ for 1h. The size and amount of $\alpha$-Al2O3 particles added by ball milling were 0.107 ${\mu}{\textrm}{m}$ and 0.5 wt%.

• Journal of the Korean Ceramic Society
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• v.49 no.1
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• pp.72-77
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• 2012

In the preparation of a hydroxyapatite [HAp]/gelatin [GEL] nanocomposite, the GEL matrix in aqueous solution of $H_3PO_4$ was modified by the introduction of aspartic acid [Asp], asparagine [Asn], and glycine [Gly]. The addition of Asp, Asn and Gly greatly affected the slurry formation of HAp/GEL nanocomposite and the resulting dry body showed variations in toughness with the addition of the different amino acids. The introduction of Asn into HAp/GEL nanocomposite was effective for producing the organic-inorganic interaction between HAp and GEL, and caused the increase of toughness. The formation reaction of the modified HAP/GEL nanocomposites was investigated by using XRD and FT-IR. The organic-organic interaction between the GEL matrix and the additives of Asp, Asn and Gly was confirmed from FT-IR analysis, and the organic-inorganic interaction between HAp nanocrystallites and the modified GEL matrix was also discussed, using FT-IR spectra patterns. Nanocrystallites of HAp were covalently bound with the GEL macromolecules and differently influenced by the modification species of Asp, Asn, and Gly.

• Journal of the Korean Ceramic Society
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• v.35 no.1
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• pp.66-78
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• 1998

the microstructure and mechanical properties of seeded and ball-milled dry gels prepared by boehmite sol-gel method were discussed. The densification of seeded gels was improved with increasing seed content namely the number of seed The number of seed was 1.09, 3.35, 5.72${\times}$1012/cm3 boehmite when seeded with 1, 3, 5wt% respectively The ball milled gel contained about 0.5wt% seed and the number of seed was 4.72${\times}$1012/cm3 boehmite. The sintered density of 5wt% seeded gel was below 80% when sintered at 1300$^{\circ}C$ for 1h. On the other hand that of ball milled gel was very improved and reached to 97% In the case of 3wt% seeded gels the density over 97% was attained when sintered at 1500$^{\circ}C$for 1h. and the grain of the sintered body was several micrometers in size. However the sintered body of ball milled gel showed grain size of submicrometer when sintered at 1300$^{\circ}C$ for 1h. And this specimen showed highest harness value of 1900kg/mm2 The fracture toughness increased with increasing sintering temperature. The sintered body of ball milled gel showed the largest grain size and the highest fracture toughness without regard to sint-ering temperature.

• KSBB Journal
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• v.17 no.1
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• pp.54-58
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• 2002

Curdlan gel containing various hydrophobic materials was prepared. The homogenized suspension of curdlan and hydrophobic materials was healed at $100^{\circ}C$. The curdlan gel can contain hydrophobic material up to 27%(v/v). When gel was compressed, only water in the gel was removed. When immersed in water, the dried gel absorbed water and became the original wet gel. The syneresis of gel decreased with the concentration of hydrophobic material added. DHA content of dried gel was about 90%. $\beta$-cyclodextrin inclusion complexes containing DHA were prepared with addition of water and ethanol. X-ray diffractograms of complexes showed a specific peak at 7-$8^{\circ}C$ and FT-IR spectrum of complex showed a specific C=O peak at $1745\textrm{cm}^{-1}$. Inclusion complex containing DHA was microcapsulated with curdlan and pullulan.

• Preventive Nutrition and Food Science
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• v.10 no.2
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• pp.191-197
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• 2005

There exist two interesting phenomena in making seafood products from surimi. When salted surimi is kept at a constant low temperature $(4\~40^{\circ}C)$, its rheological properties change from sol to gel, which is called 'setting'. Seafood processors can exploit changes that occur during setting in preparation of surimibased products, because heating at high temperatures, after the pre-heating during the setting process, enhances the gel-strength of salted surimi. Contrarily, when salted surimi or low-temperature set gel is heated at moderate temperatures $(50\~70^{\circ}C)$, a deterioration of gel is observed. The phenomenon is termed 'modori'. In the modori temperature range, heat-stable cysteine proteinases such as cathepsin B, H, Land L-Iike hydrolyze the myosins responsible for gel-formation, resulting in gel weakening modori. This article reviews molecular events occurring during gel setting that improve the quality of surimi-based products, and inhibition of modori by applying proteinase inhibitors. Application of recombinant protein technology to surimi-based products is introduced and its prospects for practical use are discussed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.232-233
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• 2006

In recent years the interest in organic/inorganic hybrid materials has increased at a fast rate. Nano organic-inorganic hybrid composites have shown advantages for preparing hard coating layers. Especially, nano hybrid composite has low environmental pollution. It has high transparency, hardness, toughness, thermal dissociation temperature, hydrophobicity by using nano sized inorganic material. There are many ways in which these materials may be synthesized, a typical one being the use of silica and silanes using the sol-gel process. The structure of sol-gel silica evolves as a result of these successive hydrolysis and condensation reactions and the subsequent drying and curing. The sol-gel reactions are catalyzed by acids and produce silica sol solutions. The silica sol grows until they reach a size where a gel transition occurs and a solid-like gel is formed. Colloidal silica(CS)/silane sol solutions were synthesized in variation with parameters such as different acidity and reaction time. In order to understand their physical and chemical properties, sol-gel coating films were fabricated on glass. From all sol-gel solutions, seasoning effect of sol-gel coating layer on glass was observed.

• Food Engineering Progress
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• v.21 no.1
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• pp.36-41
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• 2017

The release profiles of nisin from nisin-incorporating gel foods and the antimicrobial activities of the gels on the growth of Brochothrix thermosphacta in an aqueous system containing the gels have been investigated. A linear regression model was applied to determine the diffusion coefficient (D) for the diffusion of nisin in the gel. The antimicrobial activities of nisin released from 1, 2 and 3% (w/v) agar gels on the growth of B. thermosphacta in a broth medium with and without nisin were investigated. The D decreased from $1.2{\times}10^{-2}$ to $8.2{\times}10^{-3}$ and $6.4{\times}10^{-3}cm^2/s$ as the agar concentration in the gel increased from 1 to 2 and 3% (w/v), demonstrating the diffusion rate in the gels can be controlled by the agar concentration in gel. The agar gel incorporating nisin inhibited the B. thermosphacta growth in the broth medium by prolonging the lag phase. The growth inhibition was enhanced by the addition of nisin in the medium. The results of this study exhibited that the gel food is a feasible nisin delivery system with a controlled release achieved by the adjustment of agar concentration in the system, demonstrating the potential of nisin-incorporating gel for preserving particulate-containing drinks.

• Entomological Research
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• v.48 no.6
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• pp.459-465
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• 2018

The present study evaluated the efficacy of Maxforce gel baits containing 0.01% fipronil (Maxforce), 0.05% fipronil (Maxforce Magnum), 1.0% clothianidin (Maxforce Impact), and 0.6% indoxacarb (Avion gel bait; all from Bayer Environmental Science, Clayton, CA, USA) against reference and wild strains (Mobasher, Andisheh, Tamin-e Ejtemaei, and Maskoni) of German cockroach collected in 2016. Test design and bait placement were according to World Health Organization (WHO) procedures for efficacy achieving a 95% mortality rate. Although cockroaches fed on all gel baits, gel baits containing clothianidin and indoxacarb were eaten at higher rates than gel baits containing 0.01% and 0.05% fipronil. The cumulative mortality rates reached 100% for all cockroach strains at 32, 28, 28 and 40 h after eating baits containing 0.01% fipronil, 0.05% fipronil, clothianidin, and indoxacarb, respectively. Efficacy (a 95% mortality rate) after exposure (consumption) of gel baits containing 0.05% fipronil and clothianidin was seen after 28 h, compared with 32 h for 0.01% fipronil and 40 h for indoxacarb. In conclusion, commercial gel baits have improved and may be more effective than spray formulations against German cockroaches.