• Korean journal of food and cookery science
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• v.10 no.1
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• pp.80-85
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• 1994

Studies were carried out to investigate physicochemical and gelatinization properties of legume, cereal and potato starches. Cowpea, mung bean, acorn, and buckwheat starches showed similar moisture content and amylose content, however, there is neither similarity nor certaion trend in WBC, swilling power, and solubility among them. DSC thermograms of cowpea, mung bean, acorn, and buckwheat starches showed similar patterns with two endothermic peaks and relatively broad gelatinization ranges. SEM photomicrography of gelatinized cowpea, mung bean, acorn and buckwheat starches showed highly swollen and extremely disintegrated, folded structure.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.3
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• pp.358-364
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• 2001

The physiochemical properties and interactions between porcine blood and waxy rice were determined. Addition of calcium chloride (0.15%) improved acceptability of blood cake and increased the gelatinization degree of waxy rice. The water-holding capacity of porcine blood gel (blood/water=60/40, v/v), extent of absorption and gelatinization of waxy rice, and scanning electron microscopy showed that blood protein matrix and waxy rice are competitors for holding water in the cooking procedure. Non-haem iron content increased linearly (R=0.95) when heating temperature rose. The presence of blood proteins caused increasing of peak temperature (Tp) of gelatinization in differential scanning calorimetric thermal gram, The microstnlcture of plasma proteins and haemoglobin appeared continuous changes, and interacted with surface of waxy rice flour in terms of network and mosaic form, respectively. The electrophoretic patterns revealed an interaction between plasma proteins and waxy rice glutelin and haemoglobin when heated could be found at temperatures above $60^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.19 no.5
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• pp.435-440
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• 1987

Gelatinization properties of heat-mositure treated potato and sweet potato starches were investigated. Water-binding capacity of starch was increased by heat-mositure treatment, which was more pronounced in sweet potato starch. Blue value was not affected by the treatment. Amylograph viscosities were decreased by heat-mositure treatment, which was more pronounced in potato starch. Critical concentration of NaOH for gelatinization of starch increased as moisture level increased. Gel volume of starch upon KSCN gelatinization was higher in potato starch. Gelatinized starches showed Binghamapseudoplastic behavior. Consistency index and yield stress were drastically decreased upon heat-moisture treatment.

• Preventive Nutrition and Food Science
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• v.4 no.4
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• pp.215-220
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• 1999

The Physical properties of corn starch were investigated by scanning electron microscopy, X-ray diffractometry and differential scanning calorimetry during the formation of enzyme-resistant starch(RS). Samples were studied in their native states and after annealing at 50, 55, 60 and 65℃ in excess water(starch : water=1:3) for 48hr. Starch granules became smaller and more rounded after annealing than in their native state. Annealing did not change the X-ray profile of native corn starch. After autoclaving-cooling cycles, native starch lost most of its crystallinity but annealed ones showed some of their crystallinity left as diffuse or poor B-type, which didn't relate to increasing Rs yields. During formation of RS, however, both native and annealed starches changed their X-ray profile from A-type to poor B-type of retrograded amylose. Annealing caused an increase in gelatinization temperature and enthalpy, but a narrowing of gelatinization temperature range. Only starch annealed at 65℃, however, showed a decrease in enthalpy even though its gelatinization temperature increased, which appeared to be due to the partial gelatinization in the amorphous region during annealing. Peak height index(PHI), the ratio of ΔH to Ti-To, increased by annealing. PHI values, therefore, showed the possibility as an indicator to predict RS yield which cannot be differentiated by differential scanning calorimetry and X-ray diffraction data.

• Korean Journal of Food Science and Technology
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• v.16 no.3
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• pp.273-278
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• 1984

Changes in rheological properties of rice starch-water systems during the gelatinization were evaluated with the tube viscometer at temperatures between 50 and $85^{\circ}C$ and for the concentrations ranging from 3-5% rice starch. The flow consistency index increased exponentially with time at a particular temperature while being linearly dependent upon the concentration. The gelatinization rate measured by rheological method followed Arrhenius type equation. The value of activation energy of gelatinization for 5% rice starch was about 25 kcal/g mol.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.3
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• pp.226-232
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• 2012

Through the sampling four rice cultivars with differing amylose contents, the relationship between the structural and gelatinization properties of endosperm starches was analyzed. These rice varieties exhibited different chain length distribution ratio within the amylopectin cluster as well as varing amylose levels. The proportion of amylopectin short chains of in Goami cutlivars was higher than the other varieties, whereas the Goami 2 which shows amylose extender mutant properties in the endosperm showed the highest proportion of long chains. In X-ray diffraction analysis of rice starches, the Goami 2 variety displayed a B-type pattern whereas the other varieties were all A-type. Among the cultivars with high and normal rice starch levels, those with the higher amylose contents showed distinctly lower swelling. Goami 2 rice was found to have the highest onset and peak gelatinization temperature from the differential scanning calorimetry results. The four rice cultivars under analysis also showed different rates of hydrolysis by amyloglucosidase. These findings suggest that the composition and chemical structure of the starch content is a major determinant of both the gelatinization and functional properties of rice.

• Food Science and Biotechnology
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• v.14 no.4
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• pp.470-473
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• 2005

Starch was isolated from turnip (Brassica rapa L.), and to elucidate the structure-function relationship its structural and physical properties were characterized. Morphological structure of the starch was analyzed by SEM (Scanning Electron Microscopy). Most of the starch granules were spherical in shape with diameter ranging from 0.5-10mm. Apart from larger granules ($<10\;{\mu}m$) which dominated the population size of turnip starch, significant amount of small ($0.5-2\;{\mu}m$) and mid-size granules (${\sim}\;{\mu}m$) were also detected. It was revealed that presumably, erosion damages occurred due to the attack of amylase-type enzymes on the surface of some granules. Branch chain-length distribution was analyzed by HPAEC (High-Performance Anion-Exchange Chromatography). The chain-length distribution of turnip starch revealed a peak at DP12 with obvious shoulder at DP18-21. The weight-average chain length ($CL_{avg}$) was 16.6, and a large proportion (11.8%) of very short chains (DP6-9) was also observed. The melting properties of starch were determined by DSC (Differential Scanning Calorimetry). The onset temperature ($T_o$) and the enthalpy change (${\Delta}H$) of starch gelatinization were $50.5^{\circ}C$ and 12.5 J/g, respectively. The ${\Delta}H$ of the retrograded turnip starch was 3.5 J/g, which indicates 28.2% of recrystallization. Larger proportion of short chains as well as smaller average chain-length can very well explain relatively lower degree of retrogradation in turnip starch.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.2
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• pp.211-217
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• 2013

We investigated the quality characteristics of rice noodles supplemented with turmeric, purple sweet potato, or seaweed (Hizikia fusiforme). RVA (Rapid Visco Analyser), color, water activity, texture, and cooking properties were tested. Initial gelatinization temperature of noodles containing turmeric were the highest. Peak viscosity, holding strength, break down, final viscosity, and set back of noodles containing purple sweet potato were highest, indicating that the gelatinization state was more unstable and retrogradation would occur faster. The L value of the seaweed noodle was the lowest, while the a and b value of the turmeric noodles were $7.3{\pm}0.3$ and $40.2{\pm}1.3$ respectively, higher values than turmeric and seaweed noodles. Water activity of the seaweed noodle was 0.665, higher than turmeric and purple sweet potato noodles. Cooking properties (including weight, volume, and water absorption) and turbidity of seaweed noodles showed the highest growth rate. In terms of texture, the hardness was highest in purple sweet potato noodles, and the cohesiveness and gumminess was highest in seaweed noodles. The quality characteristics of rice noodles supplemented with turmeric, purple sweet potato, or seaweed showed that seaweed noodles were stable in gelatinization and cooking properties.

• Journal of the Korean Society of Food Culture
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• v.19 no.3
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• pp.359-368
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• 2004

The Physicochemical, sensory and cooking properties of functionally fortified rice with dietary fiber and chitosan were compared with regular rice when the rices were cooked with pressure and electric cookers. Moisture content of functional rice before cooking was 11.11%, which was lower than 13.72% in regular rice. Accordingly, moisture contents of functional rice samples cooked both with pressure and electric cookers were lower than those of regular rice. L value showing the degree of lightness of cooked rice was significantly higher in rice samples cooked with pressure cookers. The ${\alpha}$ value, the degree of redness and the b value, the degree of yellowness, were the highest in the functional rice cooked with an electric rice cookers. Textural measurement of hardness using a rheometer showed the highest value in functional rice cooked with a pressure cooker. The degree of gelatinization measured using differential scanning calorimetry (DSC) before cooking showed higher onset gelatinization temperature ($T_0$) and peak gelatinization temperature ($T_p$) in functional rice compared with those in regular rice. The gelatinization enthalpy (${\Delta}H$) of functional rice was lower than that of regular rice, showing that functional foe had lower gelatinization energy compared with regular rice. When the samples were stored in a refrigerator for one week, the DSC showed faster retrogradation degrees in samples cooked with electric rice cooker, having significantly higher enthalpies of regular and functional rice cooked with electric cooked compared to those cooked with pressure cookers. The functional rice samples cooked with pressure cooker had higher consumer acceptance test values compared to those cooked with electric cookers.

• Applied Biological Chemistry
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• v.38 no.4
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• pp.353-358
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• 1995

The influence of dry-heat treatment($130{\sim}220^{\circ}C$) on the gelatinization and rheological properties of corn starch(11.4% moisture) was examined. The enthalpy of gelatinization measured by differential scanning calorimetry decreased above $190^{\circ}C$. The viscosity of starch by alkali gelatinization increased as the heating temperature rised. All the values including peak viscosity on amylograms and shear stress, apparent viscosity, consistency index and yield stress of thermal-gelatinized starch dispersion showed decreasing tendencies with increasing of heating temperature from above $170^{\circ}C$ compared with those of raw starch. The apparent viscosity and yield stress of all the samples thermal-gelatinized at $90^{\circ}C$ were increased considerably with process of gelatinization time and especially their rapid increase at the early stage was observed in the $190^{\circ}C$ sample. But all the rheological parameters of $220^{\circ}C$ sample recorded very low values compared with those of the others.