• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.7
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• pp.1046-1052
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• 2003

Viscoelastic behavior of oxidized starch gel, modified with sodium hypochlorite (NaOCl) and the adding effects of protein in oxidized starch gel was studied by dynamic viscoelastic measurement. The storage modulus(G′) of starch gel increased with the increase of starch concentration. They showed higher value when starch suspension was treated to 95$^{\circ}C$ rather than 85$^{\circ}C$. Consistency of starch gel was decreased over 1.0% active Cl/g starch when heated to 95$^{\circ}C$, which means that the swelling of starch granules increased with concentration of NaOCl and showed more sensitive against shear. As the extent of oxidation increased, starch granules were easily destroyed. Therefore, it is hard to separate between compartment of leached-out amylose and that of amylopectin, which means that the ability of gel formation was reduced. When oxidized starches were gelatinized in presence of soy protein and sodium caseinate, it was found that G′ decreased, and frequency dependence of G′ and G" increased with the increased degree of oxidation in starch. The reduce of starch-protein interaction was thought to be through the dissociation of the branched amylopectin, which playa leading role in protein interaction, with the oxidation of starch.

• Korean journal of food and cookery science
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• v.19 no.6
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• pp.783-793
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• 2003

The effects of various kinds of starch (mungbean, potato, corn and a blend of potato and com starch) on the quality characteristics of muhwakwa-pyun were studied according to the storage duration. The sweetness, pH and total acidity of muhwakwa extract were analyzed, as were the Visco/Amylograph viscosity profile and DSC thermodynamic characteristics of starches. For quality characteristics, color difference, instrumental texture characteristics and sensory characteristics were compared. The sweetness of muhwakwa extract was satisfactory but the total acidity was low for Kwa-pyun manufacture. Therefore, its pH was adjusted to 3.4 by adding 10％ citric acid with an amount of 1％ of total liquid. From the Visco/Amylograph viscosity profile and DSC thermodynamic characteristics of starches, a blend of potato and com starch was found to be easy to cook and form a gel but a little more resistant than the other starches in terms of retrogradatin. Lightness (L) and yellowness (b) of Kwa-pyun increased while its redness (a) decreased by the storage. The color became whiter and the clarity decrease regardless of the kinds of starch, which became obvious after 3 days of storage. The hardness, springiness, adhesiveness and cohesiveness tended to decrease with storage, which was weak in a blend starch. The overall acceptability of Kwa-pyun made with a blend of potato and com starch was evaluated as being the best among the samples tested. Therefore, for traditional kwa-pyun manufacture manufacture mungbean starch might be replaced with a blend of potato and corn starch which is less expensive and easily available in the market nowadays.

• Journal of Pharmaceutical Investigation
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• v.14 no.3
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• pp.122-130
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• 1984

The dissolution profiles of the seven branded prednisolone tablets were determined by means of available compendium. Those tablets were stored at $40^{\circ}C,\;50^{\circ}C\;and\;60^{\circ}C$ for 15, 30 and 60 days respectively. Under the stress conditions, the dissolution efficiency showed significant changes. It is considered that the determination of shelf life of drug from these aging effects is possible because the dissolution data followed a logarithmic distribution. There were no substantial differences of dissolution between two prednisolone formulations with different particle size not larger than $100\;{\mu}m$. The effect of two starches (corn and potato) on the rate of dissolution of prednisolone from dosage form was also investigated. All marketed tablets met the requirement of the established compendium.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.3
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• pp.9-14
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• 2008

Agar-agar extracted from red algae was used as a surface sizing material for paper after filtering, bleaching, and viscosity adjustment by oxidative depolymerization. Oxidized starches from corn and tapioca were compared to agar-based surface size in the respects of paper surface modification, strength improvement, and printability. Agar-based surface size showed high strength improvement and good printability as much as starch-based ones except film forming ability, which may be improved by adding additives, and demonstrated its great potential to be used as inexpensive and high quality surface size in future.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.42-48
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• 1998

Physicochemical properties of waxy maize starch and oxidized waxy maize starch with sodium hypochlorite $(0{\sim}60\;mg\;CL_2/g\;starch,40^{\circ}C,\;pH\;10,\;3.0\;hr)$ were studied. As sodium hypochlorite concentration was increased, the content of crude lipid and crude protein of the oxidized starch were decreased. And crude protein content and whiteness was considered to show negative regression. However, the crude ash content of the oxidized starch increased significantly with oxidation and bore a positive regression to the chlorine content. There was a progressive increase in the carboxyl content with increasing oxidant level. After pasting in hot water and cooling, viscosity of the oxidized starches were drastically lower than that of native starch . As carboxyl contents of the oxidized starch increased, the solubility and swelling power was increased. When waxy maize starch treated with 0, 1.5, 3.0 and 6.0% sodium hypochlorite, temperature of initial gelatinization of oxidized starch was shown to 65, 65, 60 and $50^{\circ}C$, respectively. The oxidized waxy maize starches also form clearer pastes. Water binding capacity of the oxidized starch decreased as the degree of carboxyl group substitution increased. Waxy maize starch has polygonal and some round granules which range from about 3.7 to $20\;{\mu}m$ in diameter. Surface appearance of the waxy maize starch became rough when oxidized with sodium hypochlorite. When homogenate of the oxidized waxy maize starch solution and corn germ oil was stored under room temperature for 24 hours, the emulsion stability was considered to depend on starch concentration and degree of substitution.

• Applied Biological Chemistry
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• v.40 no.1
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• pp.48-52
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• 1997

Modified starches were used as additives to make tomato ketchup, and their effects on the rheological properties, serum separation and sensory characteristics of the tomato ketchup were examined. The magnitudes of the yield stress and the consistency index of the tomato ketchup with the additives, regarded as a Herschel-Bulkley fluid, were found to be in the order of ADA(acetylated distarch adipate)>SA(starch acetate) >HDP(hydroxypropyl distarch phosphate)>RCS(raw corn starch)>NS(no starch). The flow behavior indices of SA added ketchup and HDP added one were nearly constant regardless of the additive concentrations, whereas those of ADA and RCS increased with the additive concentration. In the serum separation test centrifugation, the ADA added ketchup showed the highest stability against separation, being fol-lowed by SA>HDP>RCS>NS. In the sensory evaluation, the magnitudes of the acceptance of the ketchup with the additives were as ADA(2%)>SA(2%)>RCS(2%)>NS>HDP(2%).

• The Korean Journal of Food And Nutrition
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• v.28 no.1
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• pp.126-133
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• 2015

Ohmic heating uses electric resistance heat which occurs equally and rapidly inside food when the electrical current is transmitted into. Prior to the study, we have researched the potato starch's thermal property changes during ohmic heating. Comparing with conventional heating, the gelatinization temperature and the range of potato starch treated by ohmic heating are increased and narrowed respectively. This result is appeared equally at wheat, corn and sweet potato starch. At this study, we treated potato, wheat, corn and sweet potato starch by ohmic/conventional method and observed change of external structure by microscope and internal structure by X-ray diffractometer. Conventional heated at $55^{\circ}C$ potato starch was not external structural changes. But ohmic heated potato starch is showed largely change. Some small size starch particle were broken or small particles are made of larger particle together or small particles caught up in the large particle. Changes in ohmic heated potato starch at $60^{\circ}C$ was greater. The inner matter came to an external particle burst inside and only the husk has been observed. The same change was observed in the rest of the starch. The change of internal structure of potato starch was measured using X-ray diffraction patterns. There was no significant difference between ohmic and conventional heating at $55^{\circ}C$. But almost every peak has disappeared ohmic at $60^{\circ}C$. Especially $5.4^{\circ}$ peak to represent the type B was completely gone. When viewed from the above results, external changes with change in the internal crystal structure of the starch particles were largely unknown to appear. In conclusion, during ohmic heating changes of starch due to the electric field with a change in temperature by the heating was found to have progressed at the same time.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.6
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• pp.861-868
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• 2021

To confirm the influence of modified starch on frozen storage stability, the microstructure and sensory characteristics of fish cakes, called Eomuk in Korea, by using seven varieties of starch, including native starch (NS), physically treated corn starch (MS) and modified starch [treatment with acetate (SA-1, SA-2 and SA-3), hydroxypropyl (HS), and acetylated distarch adipate (ADA)] were evaluated. Scanning electron microscopy (SEM) photographs showed fish cakes with NS had a finer and denser network structure than those made with modified starches. During frozen storage, fish cakes with HS and ADA exhibited a stable structure, as evaluated by porosity and rough surface. The results of the sensory evaluation showed that modified starch, including HS, SA-2 and ADA, increased the taste and firmness of the fish cakes, while NS, MS and the modified starch SA-3 resulted a decrease in the sensory properties during storage. Therefore, HS, SA-2 and ADA are suitable additives to improve the sensory quality of frozen fish cakes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1251-1257
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• 2008

For the first 42 days, we made rats obese by feeding them potato starch instead of corn starch and after that we fed them transformed potato starch by 4 groups for 70 days. The 4 groups are GPS group, SPS group, EZ group and H40 groups and each were fed normal potato, small potato, enzyme treated potato, and acid treated potato starches, respectively. We determined body weight and feeding efficiency, lipid profiles in serum, lipid peroxidation in tissues and redox antioxidant system as GSH and GP-x in vivo. As a result, there was no difference in the increment of body weight in the groups of GPS, EZ and H40. Therefore EZ group showed lower body weight increment than other groups. While GPS group and SPS group did not show significant difference in blood glucose, cholesterol level, LDL-cholesterol and TC, and their measured values were lower than those of EZ and H40 groups. No significant difference was found in HDL-cholesterol level except for GPS group. Furthermore, when calculating atherogenic index (AI) by HDL-cholesterol and TC contents, H40 group showed higher measured value than other groups. When measuring the lipid peroxidation in serum, kidney and liver tissues, the serum lipid peroxidation in H40 group was higher than others. In the tissue of liver and kidney, EZ and H40 groups showed significantly lower contents than others. The content of GSH showed different tendency in each tissue, but the measured value of GP-x activity was lower in SPS group.

• Applied Biological Chemistry
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• v.18 no.2
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• pp.102-108
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• 1975

Acorn starch preparation and some of its characteric study were made. The results obtained were as follows. 1) Yearly production of acorn in Korea is amounted to be 1,200,000 l approximately. The content of its carbohydrate was found to be 72.8%, so that this would be considered as one of good resources of starch in our country. 2) The major moieties of tannin constituents of acorn were found to be the gallic acid, catechin and chlorogenic acid. 3) The type of acorn starch granules were short oval shaped having the diameters of that were in the range of $3.5{\sim}5.2{\mu}$ and $8.0{\sim}19.5{\mu}$, respectively. 4) Initial gelatinifalion teniperaiure of acorn starch was $62{\sim}64^{\circ}C$, similar to those of corn and wheat starch. 5) Alnylose content of acorn starch were 27.1%, which is lower than that of barley but higher than that of potato starch. 6) The raising power of the acorn starch was 12.4, which is higher than that of the potato starch but lower than those of common cereal starches. 7) The blue value of acorn starch was 0.43, similar to that of wheat starch and higher than those of wheat potato and rice starch but lower than that of barley starch. 8) The alkali number of the acorn starch was 11.03, similar to that of corn starch but higher than those of barley and rice starch.