• Journal of Ginseng Research
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• v.8 no.2
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• pp.124-134
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• 1984

Ginseng root starch, prepared by conventional method, contained crude lipid of 0.5%, crude protein of 0.4%, crude mineral of 0.17% and phosphorous of 12.5mg% as noncarbohydrate constituents. The amylose content of ginseng root starch picked in Summer (May to August) and Winter (November to March) was 32-35% and 15-20%, respectively, and it was decreased with a growing preiod of ginseng. The blue value, alkali number and ferricyanide number of the starch were 0.14-0.17, 8.50 and 0.781, respectively. The molecular weight of amylose in the starch was estimated to be 1.27-7.95${\times}$105 by means of periodate oxidation, and the degree of branching and glucose unit per segment of amylopectin were 3.50-3.53% and 28.3-28.5, respectively, The starch content of ginseng root was decreased when dried under sunlight and stored at 5$^{\circ}C$ for twenty days. In contrast, sucrose content in the root was increased from 3.8% in fresh state to 11.5% during storage at the above condition. In the other hand, starch was converted to maltose by heating at temperature above 70$^{\circ}C$.

• Membrane Journal
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• v.11 no.4
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• pp.161-169
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• 2001

Single and mixed particle suspensions of kaolin, bentonite, starch and PMMA were carried out using a dead-end Amicon fi1tration cell with microfilteration membranes. The experimental data of permeate fluxes were fitted by the constant pressure fi1tration models in order to investigate fouling steps. In 0.1 wt% mixed solution of equal amount of kaolin and starch, the permeation flux was about 30% lower than the average of each particle flux. However, the permeation flux for kaolin/PMMA mixed solution was about 10% higher than the average of each particle flux. In the cases of bentonite and PMMA or starch mired solution, the improvement effect on permeation flux was weaken than that of kaolin mixed solution. Also, the membrane fouling resistance for mixed particle solution of equal amount of kaolin and starch was minimum at 0.05 wt% particle concentration.

• Food Engineering Progress
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• v.21 no.4
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• pp.341-350
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• 2017

The relationship of in vitro starch digestibility and gel strength was investigated at various concentrations (10-30%) of rice cultivars with different amylose contents (27.9, 17.9, and 5.2%). As the rice flour concentration increased, predicted glycemic index decreased, but gel strength increased regardless of amylose contents. Gel strength correlated strongly with amylose content, whereas in vitro starch digestibility was more highly affected by rice flour concentration than by amylose contents. Moreover, the impact of degree of gelatinization on in vitro starch digestibility of high amylose rice was also examined in terms of structural features and rheological properties. The digestion rate of fully gelatinized flour was 1.7 times higher than that of native flour, while the disrupted structure with a different gelatinization degree during starch digestion was visually demonstrated through the X-ray diffraction and molecular distribution analysis. The rice flour changed from an A-type to a V-type pattern and showed difference in crystalline melting. The low molecular weight distribution increased with increasing degree of gelatinization during starch digestion. The apparent viscosity also increased with degree of gelatinization. These results demonstrated that the starch digestibility of rice was more affected by concentration than by amylose content, as well as by the degree of gelatinization due to structural difference.

• Composites Research
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• v.35 no.6
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• pp.419-424
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• 2022

Using non-biodegradable polymers is a severe environmental problem as they are not recyclable and generate a large amount of waste. Biopolymers, such as starch-based composites, have been considered one of the most promising replacement materials. These eco-friendly materials have the advantage of being low-cost, biodegradable, and obtained from renewable sources. However, as starch tends to be brittle and hydrophilic, it can make these materials unusable when exposed to water and limit its processability for further applications. In this work, a biobased modified starch was grafted using two bioderived materials, lauryl methacrylate (LMA) and tetrahydrofurfuryl methacrylate (THFMA), by radical polymerization. A polylactic acid (PLA) composite based on the modified starch (m-St) was fabricated to enhance its toughness. These samples were characterized by Fourier transform infrared, ¹H NMR and ¹³C NMR analysis, optical and scanning electron microscopy. The starch was successfully grafted, thus improving the compatibility with the PLA matrix. The mechanical properties of these films were also studied. Results from mechanical tests showed a slight enhancement of the mechanical performance of these composites when m-St was added to the PLA matrix. Such behavior is related to the improved dispersion of m-St 1:2 on PLA, confirmed by SEM images showing enhanced compatibility between modified starch and PLA matrix. This indicated excellent properties of the produced composite film for further eco-friendly applications.

• Journal of Microbiology and Biotechnology
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• v.34 no.4
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• pp.891-901
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• 2024

This study focuses on improving the 3D printability of pea protein with the help of food inks designed for jet-type 3D printers. Initially, the food ink base was formulated using nanocellulose-alginate with a gradient of native potato starch and its 3D printability was evaluated. The 3D-printed structures using only candidates for the food ink base formulated with or without potato starch exhibited dimensional accuracy exceeding 95% on both the X and Y axes. However, the accuracy of stacking on the Z-axis was significantly affected by the ink composition. Food ink with 1% potato starch closely matched the CAD design, with an accuracy of approximately 99% on the Z-axis. Potato starch enhanced the stacking of 3D-printed structures by improving the electrostatic repulsion, viscoelasticity, and thixotropic behavior of the food ink base. The 3D printability of pea protein was evaluated using the selected food ink base, showing a 46% improvement in dimensional accuracy on the Z-axis compared to the control group printed with a food ink base lacking potato starch. These findings suggest that starch can serve as an additive support for high-resolution 3D jet-type printing of food ink material.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.1
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• pp.39-46
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• 2004

Waxy maize starches are inherently stable in soluble status and can be chemically modified to improve stability along with heat, acid and shear resistance. This study was carried out to investigate the effect of theological and sensory characteristics of the yellow layer cake made by adding different levels of waxy maize starch as a fat substitute for shortening. By increasing the substitution level of waxy maize starch for shortening, the specific gravity of cake batter increased and the viscosity decreased. The microstructures of cake crumb observed by the scanning electron microscope were not different significantly, and the size of air cells and fat particles also were not substantially decreased by increasing fat substitution level. The texture profile analysis using texture analyzer decreased by increasing the different substituting levels of waxy maize starch. Among various sensory properties, the color value of layer cake increased by increasing the level of waxy maize starch. However, the appearance, flavor, taste, texture and overall preference decreased.

• Korean Journal of Food Science and Technology
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• v.20 no.6
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• pp.850-855
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• 1988

Rheological propreties of defatted and 1% palmitic arid reincorporated rice starch solutions were investigated, comparing with nondefatted starch. Flow behavior of gelatinized starch solutions(3-7%) revealed pseudoplastic behavior with yield stress, but yield stress was decreased by defatting. Relationship between logarithmic consistency index and concentration of nondefatted starch solution was linear with single slope, but the slopes for defatted and reincorporated starch solutions were different at 3-5% and 5-7% starch concentration. The activation energies for 7% starch solutions were estimated to be 3.14-4.76 kcal/g mol and increased slightly by defatting. All thre starch solutions above 4% concentration exhibited hysteresis phenomena, but by defatting, humping phenomena was observed and thixotropic behavior were increased slightly.

• Microbiology and Biotechnology Letters
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• v.14 no.5
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• pp.407-413
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• 1986

In an agitated bead reaction system, the enzymatic saccharification of uncooked starch was substantially enhanced. The enhancement mechanism was investigated front the view of the structural aspect of starch. The mechanical impact caused by the movement of the attrition-milling media resulted neither the destruction of microcrystalline structure nor the fragmentation of starch granule. instead, the most distinct phenomenon was the swelling of starch granule up to about 2.5 times, and the swelling mechanism was not similar with that caused by cooking. However, in the case of the enzyme addition in the attrition coupled reaction system, the swollen starch was easily fragmented into the large number of small particles by the synergistic action of the enzyme and milling-media. The exposed surface area of the fragmented particles plays the major role in enhancing the saccharification. The saccharification rate was quite different depending on the source of starch, the reason was discussed in terms of the granular structure of uncooked starches.

• Polymer(Korea)
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• v.24 no.2
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• pp.141-148
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• 2000

Polycaprolactone (PCL) was blended with corn starch to produce biodegradable compost films and the biodegradability and mechanical properties were investigated. As the compatibilizer for the immiscible PCL/starch blend, 2-hydroxyethylmethacrylate (HEMA)-PCL macromer was grafted onto starch by initially grafting HEMA to starch and then grafting of PCL onto HEMA via ring opening polymerization of $\varepsilon$-caprolactone. When biodegradability of the PCL grafted starch-g-DEMA copolymers was compared with that of starch by the modified Sturm test, graft copolymers degraded at much slower rates due to the presence of the non-degradable HEMA. With the addition of the graft copolymer up to 5 wt% to the blend, the elongation-at-break of the starch/PCL blend increased substantially, while the tensile strength and modulus did not change much. SEM observation of the blend containing 2 wt% copolymer clearly indicated that the interfacial adhesion between the starch and PCL was strengthened by the copolymer.

• Korean journal of food and cookery science
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• v.6 no.2
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• pp.7-14
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• 1990

This study has been carried out in order to investigate the physicochemical properties of two small red bean starches. Some of rheological properties of the starch gels were also studied by experiments of various starch concentrations. Water binding capacity of black bean starch was 172.3% and that of red bean starch was 199.0%. Black bean starch had lower swelling power than red bean starch, but the solubility of the black bean starch was higher. When the temperature increased from 60$^{\circ}C$ to 70$^{\circ}C$, the transmittance of two starches rapidly increased. The gelatinized temperature in DSC for black bean was 66.2$^{\circ}C$ and that for red bean was 66.0$^{\circ}C$. Black bean and red bean starches had the blue vlaues of 0.55 and 0.56 and the alkali numbers of 4.40 and 4.13. The molecular weight of amylose was 40,000 and 33,611. The amylose contents of two starches were same at 52%. Brabender Amylographs of two small red bean starch pastes showed C pattern, which is stable. The results of compression test pointed out that TPA parameters varied with the change of storage time, and black bean starch gels had the higher TPA value. The retrogradation study by glucoamylase digestion method revealed that red bean starch gels were more easily retrogradated than black bean. X-ray diffraction patterns of two small red bean starches were A pattern, and diffraction peaks disappeared with gelatinization of starches.