• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.766-771
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• 1989

physicochemical properties of rice starch isolated from eight varieties were examined to evaluate the rice processing suitability The amylose contents of rice starch were varied with 16.7-29.7%, and IR 30, Godael, Aguja and Lengkwang varieties showed higher amylose content than the other varieties. The water binding capacity and blue value were in the range of 87.0 103.0 and 0.178-0.305, respectively. As the amylose content increased, the amylogram pasting temperature and the break down ratio increased, while the peak viscosity did not show any significant difference. The transmittance of 0.1% starch suspension slowly increased at $50^{\circ}C$ in the low-amylose content rice group, and rapidly increased at $65^{\circ}C$ in the high-amylose content rice group, but there were no differences above $75^{\circ}C$ among varieties. Also the low-amylose rice starch showed higher values in the swelling power and solubility. The hardness of the 30% rice starch gels was low in low-amylose one. During storage at $20^{\circ}C$ for 14 days, the increment of hardness was more slow in high-amylose one. The retrogradation velocity constant of rice starch gel by Avrami equation was the highest as 0.219 in Aguja variety.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.652-657
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• 2007

This study was performed to evaluate the physicochemical and quality characteristics of bread with Enteromorpha intenstinalis added. In order to compare the physical and organoleptic properties, 1 to 4% of E. intenstinalis powder was mixed with the flour. Among the physical characteristics of the dough, the absorption ratio in the farinogram and the degree of attenuation increased with increasing amounts of E. intenstinalis powder, whereas the development time, dough stability, the degree of extension, the degree of resistance, and R/E became reduced. In the amylogram, there was no difference in the gelatinization starting temperature among the samples, but the maximum viscosity gradually increased according to increasing amounts of E. intenstinalis powder. Also, a sensory evaluation was carried out in terms of acceptability (color, flavor, moistness, tenderness, mouth feel, and overall acceptability). Taken together, the 2% treatment showed the highest evaluation values, as compared to the other treatments.

• Journal of Adhesion and Interface
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• v.10 no.4
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• pp.191-198
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• 2009

UV-curable aliphatic epoxy acrylates were prepared by the reaction of glycerol diglycidyl ether (GDE) with 2-carboxyethyl acrylate (2-CEA) or 2-hydroxyethyl acrylate (2-HEA). The structures of the epoxy acrylates were characterized by FT-IR, $^1H$-NMR, and $^{13}C$-NMR and the yield was obtained by prep-LC. The UV- and the thermal-curing behaviors of the product were investigated using photo-DSC and DSC, respectively. The reactivity of 2-CEA was higher than 2-HEA and the yield of the product (GEA-C) which was prepared using 2-CEA was about 83%. The maximum UV-curing time ($T_{max}$) of the GEA-C contained non-reactive components and by-product was about 10 seconds. The GEA-C showed low color difference (${\Delta}E^*$), low viscosity, and good thermal stability - its value was 2.51, 192 cps, and $299^{\circ}C$ (at 5% weight loss), respectively. The activation energies ($E_a$) of thermal-curing reaction calculated from Kissinger and Ozawa-Flynn-Wall method were 91~92 kJ/mol.

• Journal of Ginseng Research
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• v.32 no.3
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• pp.238-243
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• 2008

Comparison of the physico-chemical characteristics were investigated among white (WG), fermented (FG) and red ginseng (RG) extracts. We observed maximum contents of extractable solids in FG, but viscosity was lower than other ginseng extracts. The contents of ash and crude protein of FG were higher than those of other ginseng extracts. The contents of carbohydrate were similar, but component Na and cruid lipids were maximum in RG. we extended our study on comparison of the calories among WG, FG and RG. We noticed that comparison of the calories among WG, FG and RG showed insignificant difference.

• Korean journal of food and cookery science
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• v.22 no.6 s.96
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• pp.923-929
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• 2006

Sponge cakes were prepared by replacing wheat flour with rice flour ranging from 10-40% and their physico-chemical, textural and sensory properties were examined. Rice flour addition decreased the moisture content and increased the total sugar and protein contents of the sponge cake. The viscosity and specific volume of batter increased with rice flour addition. 'L' values of crumb of sponge cakes with 20% or more rice flour were lower, whereas corresponding 'a' values were higher than those of the control. Textural hardness was increased, and textural cohesiveness and springiness were decreased with the addition of 30% or 40% rice flour. perceived that sponge cake with 20% or more rice flour had a weaker sweet flavor than the others. With the addition of 30% or 40% rice flour, sponge cake showed a stronger roasted and weaker greasy flavor, and less softness and cohesiveness than the other sponge cakes. The sensory did not find my significant difference in overall acceptability between the control and rice flour-added sponge cakes. Therefore, wheat flour could be replaced by rice flour up to 40% without reducing acceptability.

• Korean Journal of Materials Research
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• v.8 no.2
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• pp.135-140
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• 1998

Drag reduction produced by dilute solution of water soluble ionic polymer-surfactant complex under turbulent flow in a rotating disk apparatus(RDA) was investigated in this study. Three different molecular weights of polyacrylic acid(PAA) were adopted as drag reducing additives, and distilled water was used as a solvent. Experiments were undertaken to observe the dependence of drag reduction on various factors such as polymer molecular weight, molecular expansions and flexibility, rotating speed of the disk and polymer concentration. Specific considerations were put on conformational difference between surfactant and polymer, and effect of pH on ionic polymer possessing various molecular conformation through pH. The complex of ionic polymer and surfactant(Sodium Dodecyl Sulfate) behaves like a large polyelectrolyte. Surfactant changes the polymer conformation and then increases the dimension of the polymer. The radius of gyration, hydrodynamic volume and relative viscosity of the polymer-surfactant system are observed to be greater than those of polymer itself. Such surfactant-polymer complex has enhanced drag reduction properties.

• Culinary science and hospitality research
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• v.18 no.5
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• pp.243-255
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• 2012

This research has been conducted to develop the best recipe for brown sauce containing freeze-dried Salicornia powder. For this purpose, we made brown sauces with different contents of freeze-dried Salicornia powder and performed physico-chemical characteristic and sensory test. The highest salinity of freeze-dried Salicornia powder was 0.15% when 1% freeze-dried Salicornia powder was added to distilled water, SP1. The highest brightness of brown sauce was achieved with 1.2% freeze-dried Salicornia powder and was 45.29 with BSP12. More powder led to significant increases of the samples(p<0.001) in salinity and brightness. DPPH radical scavenging increased with greater freeze-dried Salicornia powder. Taste was highest at 6.36 with 0.6% powder and there was no significant difference compared to BSP6 and BSP9. Based on these findings, it was concluded that the brown sauce with Salicornia has antioxidative characteristics and the best salinity is achieved with 0.6% freeze-dried Salicornia powder. Salicornia had enough salinity to substitute salt to a certain degree and improved the quality of brown sauce in terms of the sensory test.

• KSBB Journal
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• v.16 no.4
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• pp.321-326
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• 2001

The change of molecular weight inside and outside a capsule produced using coencapsulating technology was investigated. Chitosan and chitosanase were enveloped in this membrane and product released was a loaded the medium by the principle of size exclusion. The leakage of substrate corresponding to the agitation speed was controlled by adjusting the alginate and CaCO$_3$ concentrations. The optimal condition of alginate concentration and agitation speed were 0.5% and 40rpm, respectively. Membrane thickness and capsules diameter were 10 $\mu$m and approx. 3.0 - 1.5 mm, respectively. Molecular weight difference by concentration and alginate viscosity were of little significance. In accordance with the molecular weight distribution versus enzyme concentration relationship, low concentration of enzyme produced high molecular weight oligosaccharides. At a 1.5 mm capsule size the product diffusion rate to outer surface highest. The molecular weight distribution of the released oligosaccharides was ranged from 1000 to 6000 Da. More than 80% of the initial activity of encapsulated enzyme retained after 8hrs of reaction.

• Food Science and Preservation
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• v.21 no.4
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• pp.491-499
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• 2014

Changes in various physicochemical and sensory characteristics of Samgyetang retorted at the $F_0$ values of 4.0 (F4), 7.0 (F7), and 10.0 (F10) were investigated during storage at $25^{\circ}C$ for 12 months. The pH level tended to decrease in all the treatments with the increase of the storage time, but no significant difference in the extent of the decrease was observed among the treatments. The values of volatile basic nitrogen, thiobarbituric reactive substances, and carbonyl contents increased rapidly over the storage period in the order of F4 > F7 > F10. The viscosity decreased most sharply between month 0 and month 2, after which the rate of increase declined. The oxygen concentration in the headspace of the retort pouch of the Samgyetang was higher for the samples retorted at higher $F_0$ values. In the sensory tests, the scores of the samples retorted at higher $F_0$ values tended to be lower, but all the characteristics of the samples, except for the texture of the T10 samples, were evaluated with scores higher than 5.0, the limit of marketability, over the storage time. In conclusion, the quality of the Samgyetang samples treated at higher $F_0$ values deteriorated more noticeably during storage.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.2
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• pp.152-158
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• 2015

In order to investigate the feasibility of stone dust sludge as fine aggregate, an experimental study was performed on cement mortar with stone dust sludge. fresh mortar properties and strength with various stone dust sludge replacement ratios were estimated. the replacement ratio adopted in this study was 0, 10, 20, 30%. Flow, air content, and rheological properties were considered as properties of fresh mortar. Compressive strength and flexural tensile strength were measured for strength. The results are as follows. Higher amount of stone dust sludge caused reduction in slump and air content. In the rheological properties, both yield stress and plastic viscosity increased as stone dust sludge content increased up to 20% replacement ratio, but there were no remarkable difference between 20 and 30%. Yield stress increased drastically between 10 and 20%. Compressive and flexural tensile strength results indicated that the strength variation was not significant according to stone dust sludge content, but the strength gain in the early age by adding stone dust sludge was evident. the strength at the age of 28 days however did not show noticeable effect of adding stone dust sludge.