• Analytical Science and Technology
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• v.24 no.4
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• pp.249-255
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• 2011

Swelling of starch granules by water-sorption causes a progressive or sometimes abrupt change in sorption behavior as a result of structural alterations and the possible exposure of new sites with high affinity for water. It is thus of interest to examine the time-dependent change in the size or shape of the starch granules. Gravitational field-flow fractionation (GrFFF) utilizes the earth's gravity as the external field, and is useful for separation of micron-sized particles with larger particles eluting earlier than smaller ones. In this study, GrFFF was used to monitor the swelling of two starch granules, potato starch and sweet potato starch during contact time of 11-12 days at room temperature in water. Results from GrFFF were compared with those obtained from optical microscope (OM). For both starch granules, the mean sizes were increased with time spent in water.

• Polymer(Korea)
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• v.34 no.1
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• pp.58-62
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• 2010

The acrylic monomers were graft-polymerized to starch as matrix polymer by emulsion polymerization. Viscosity and particle size of the emulsion were increased with starch contents due to interaction with water and particle swelling toward the water phase by hydroxy group of starch. Chemical stability of the emulsion was also increased with enhancement of starch, but water and alkali resistance were reduced with increasing starch contents because of the increasement of hyrophilicity. Opacity of the starch-acrylic emulsion compound containing calcium carbonate was decreased with contents of starch by its intrinsic color. The film of starch-acrylic polymer showed more clear appearance with increasing starch contents owing to enhancement of amorphous state.

• The Korean Journal of Community Living Science
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• v.23 no.3
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• pp.233-243
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• 2012

This study was performed to determine the quality characteristics of Jeungpyun with added modified starch. The addition of modified starch did not change the pH level of the samples, but it did increase the volume. The b-value of Jeungpyun with 3% modified starch was significantly lower than that of the control group. The addition of 3% modified starch also significantly increased the hardness, adhesiveness, gumminess and chewiness of the experimental group over the control group. In the test of sensory characteristics, the cell size of Jeungpyun with 2 and 3% modified starch was larger than that of the control group. Cell uniformity of Jeungpyun with 2% modified starch was lower than that of the control group. The hardness of Jeungpyun with modified starch was significantly higher than that of the control group. In the test of taste preference, Jeungpyun with modified starch beat the control group substantially. The quality of Jeungpyun with 1 and 3% modified starch showed a higher overall score than that of the control group.

• Korean journal of food and cookery science
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• v.29 no.6
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• pp.833-839
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• 2013

Separated normal and waxy rice starches were pulverized, and the physicochemical and digestive properties of the starches were determined. The size of both starch granules significantly decreased (less than $8{\mu}m$) after pulverization. For pasting properties, significant decreases of peak and setback viscosity were observed in both of pulverized starches than in native ones. The lower pasting temperature as well as increased solubility and water binding capacity of pulverized starches imply molecular degradation of starch by pulverization. For thermal properties, onset temperature and melting enthalpy significantly decreased after pulverization, especially in normal rice starch, however there was no difference in amylose-lipid complex before andafter pulverization. The slowly digestible and resistant starch portion of normal rice starch increased after pulverization, however, in waxy rice starch, the rapidly digestible portion increased.

• Journal of Ginseng Research
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• v.8 no.2
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• pp.114-123
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• 1984

This study was conducted to investigated the morphology and distribution of starch granule in ginseng root. The results obtained are as follows; The starch contents of main and lateral ginseng 1$.$cot were 23-32% and 14-16%, respectively, and it was varied significantly with growing season, namely 15-37% in Summer (May to August) and 3-6% in Winter (November to March). Thus the starch content of ginseng root was different depending on the portien of ginseng root and growing seasons, but a significant difference was not observed by a growing period of ginseng. The starch granules showed nearly round or oval shape having the diameter 2-8${\mu}$ and their size were increased with a growing period of ginseng. The crystalline structure of starch granules was found to be B-type by X-ray diffraction study.

• Journal of Ginseng Research
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• v.9 no.2
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• pp.270-284
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• 1985

In order to investigate the change of physicochemical properties of ginseng root starch during storage and heat treatment, the roots were stored for 15 days at 5 $^{\circ}C$, 15 $^{\circ}C$, 3$0^{\circ}C$ and 45$^{\circ}C$, and heated for 15 hours at 6$0^{\circ}C$, 7$0^{\circ}C$, 8$0^{\circ}C$, 9$0^{\circ}C$, respectively. The starch content was decreased from about 40% to 23-26% and sucrose content was increased from 4% to 12-16% during storage for 15 days at 5-45$^{\circ}C$. Maltose, which was not detected in fresh samples, was increased up to 8.5% during storage or heat treatment. Granular size of the starch was decreased and some of the granules were broken during storage. Amylose content in the starch was decreased from 33% to 20%, and blue value and alkali number of the starch were increased slightly, and solubility and swelling power of the starch were decreased during storage. 3 The higher storage temperature and the longer storage time, the starch was more susceptible to gelatinize, and the viscosity of the starch was lowered with the susceptibility of gelatinization. The susceptibility of degradation of the starch by the amylase was increased and amylolytic activities in ginseng root were, also, increased during storage.

• Korean Journal of Food Science and Technology
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• v.52 no.4
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• pp.423-426
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• 2020

This study was performed to investigate how the addition of starch nanoparticles prior to whipping could affect the quality characteristics and stability of full-fat dairy cream. Starch nanoparticles were prepared by dry heating under mildly acidic conditions and added to dairy cream as amount of 1, 3, and 5% (w/w). The whipped cream's storage stability, viscosity, overrun, and droplet size were investigated in combination with various starch nanoparticle contents. The storage stability and apparent viscosity increased in parallel with the increasing starch nanoparticle content compared to the control. The mean size and homogeneity of the droplets in the whipped cream increased with higher starch nanoparticle addition levels. Even though the whipped cream overrun was reduced by the addition of starch nanoparticles, the 1% addition level exhibited a similar overrun value as the control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.5
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• pp.653-658
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• 2017

To evaluate the effects of amylose content and dissolution media on the molecular structure of maize starch, changes in the hydrodynamic diameter of starch molecules were assessed via dynamic light scattering depending on amylose content and dissolution media. As the amylose content of starch increased, the hydrodynamic diameter of starch molecules proportionally decreased from 204 to 92 nm. To alter ionic strength, hydrogen bonding, or polarity of dissolution media, various contents of NaCl (1, 2, or 3 M), urea (1, 2, or 3 M), or 1-butanol (0.1, 0.5, or 1.0%) were added to media, respectively, resulting in increased hydrodynamic diameter of starch. However, the degree of expansion was dependent on amylose content and the concentration and/or type of additive. The hydrodynamic diameter of starch molecules exhibited significant correlation with amylose content obtained by size exclusion chromatography, regardless of dissolution conditions.

• Food Science of Animal Resources
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• v.32 no.2
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• pp.155-161
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• 2012

This study was carried out to investigate the encapsulation of lactic acid in starch matrix for the application into emulsified sausages. For the encapsulation of lactic acid in starch, the extrusion method was applied, by the different extrusion pressure level. The particle size and morphology of lactic acid containing starch granules and the rate of release of lactic acid from those granules were determined by using Mastersizer$^{(R)}$, a scanning electron microscopy, and electrical conductivity. The size varied slightly depending upon the extruder pressure and influenced entrapment efficiency. Lactic acid was released more slowly, when the extruder had fewer holes, which meant higher extrusion pressure, than when the extruder had more holes. Extruder pressure is therefore critical for producing finer granules that can retain lactic acid longer, during the processing of meat products.

• Elastomers and Composites
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• v.43 no.4
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• pp.221-229
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• 2008

Starch as matrix polymer was used to do graft copolymerization with 2-ethylhexylacrylate, methyl methacrylate and acrylic acid. The polymerization was carried out by radical emulsion polymerization with increasing contents of starch. When 0.174% of $\alpha$-amylase as enzyme for starch was added, it was found that it made the best stable emulsion. The glass transion temperature of the polymerized material was increased with starch contents. The particle size and viscosity of the emulsion increased with starch contents due to the increased hydroxy group. Peel strength also increased with contents of starch because the enhanced hydroxy group caused to increase affinity between substrate surface and polymer materials. However, the initial tackiness decreased with starch contents owing to film hardness by higher glass transion temperature.