• Korean Journal of Food Science and Technology
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• v.19 no.2
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• pp.97-101
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• 1987

Physicochemical properties of heat-moisture (18, 21, 24 and 27%) treated naked barley (Youngsanbori) starch indicated that crystailinity of the starch was decreased upon treatment and water-binding capacity drastically increased as the moisture level increased. The swelling power was decreased, but the solubility increased by heat-moisture treatment. Apparent viscosity in aqueous sodium hydroxide solution was repressed as moisture-treatment level increased. Amylograph hot paste vicosities were decreased upon treatment except initial pasting temperature.

• 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.

• The Korean Journal of Food And Nutrition
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• v.24 no.4
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• pp.602-606
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• 2011

찹쌀전분의 고압처리시 pH 3~10 조건에서 고유점도는 1.328~1.426 ml/g 범위로 원료전분(1.15 ml/g)보다 낮았다. 특히, 고유점도는 산성 및 알칼리성 조건에서 감소하였다. 전분의 호화과정 중 열에너지량을 나타내는 호화엔탈피는 pH 3, 4 및 5 조건에서 고압처리한 찹쌀전분이 각각 13.86, 13.47 및 13.42 J/g으로 원료전분(16.3 J/g)보다 낮은 값을 보였다. 찹쌀전분의 호화온도 및 엔탈피 감소는 고유점도가 낮아지는 현상과 일치하였다.

• Korean Journal of Food Science and Technology
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• v.17 no.1
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• pp.33-36
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• 1985

Some properties of starches from three naked barley cultivars(Songhak, Youngsan and Jinan 56) were compared. No significant differences in water-binding capacity, amylose content, relative crystallinity, swelling power and gelatinization degree at various pasting temperatures among cultivars were observed. However, starches showed characteristic viscograph indices and viscosity development patterns in aqueous sodium hydroxide solution. Songhak starch exhibited the lowest pasting temperature and was the most resist to alkali gelatinization.

• Applied Biological Chemistry
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• v.51 no.3
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• pp.207-211
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• 2008

In order to understand the difference in rice eating quality, two rice varieties having different eating qualities were examined from the correlation between palatability score (Toyo value) and components of lipid in rice endosperm. We also analyzed the relationship between lipid properties and physicochemical characteristics of milled rice. Major fatty acids of milled rice starch-lipids, known to exist as inclusion complexes with amylose in starch granules, were palmitic (38.25% in Gopum and 39.75% in Palgong) and linoleic aicds (33.13% in Gopum and 31.93% in Palgong). In addition, the unsaturated fatty acid contents of rice endosperm showed a significant relationship with palatability. Plant sterols in two rice samples were identified, Gopumbyeo of good eating quality had high contents of squlaene and cycloartenol and similar contents of campesterol, stigmasterol and sitosterol. There were significant differences in pasting properties of rice flours and starches between the two cultivars. These results suggested that rice lipids impact on pasting properties after cooking, subsequently relating to palatability.

• Applied Biological Chemistry
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• v.30 no.4
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• pp.315-322
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• 1987

Attempts were made to unravel the differences in the textural properties between a dry type, Wonki and a moist type, Chunmi sweet potato. The changes in the ingredients, cellular shapes, degree of gelatinization and hardness of sweet potatoes during baking were studied. Alcohol insoluble solid, starch and protopectin contents and activities of amylase and polygalacturonase of Wonki sweet potato were higher than those of Chunmi sweet potato. The cell sizes were smaller and the number of starch granules within the cells were higher in Wonki than in Chunmi. Gelatinization occurred in Wonki more lately than in Chunmi during baking. The difference in hardness after baking between Wonki and Chunmi was found distinctively. But both samples were gelatinized completely, the difference in hardness was not found.

• Korean journal of food and cookery science
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• v.5 no.1
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• pp.53-62
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• 1989

Granular shapes and size, physicochemical properties and gelatinization properties of potato starches from Irish cobber (the dry type), Dejima (the moist type), Shepody and Superior were investigated. The starch granule was round or oval and the size of Irish cobbler and Shepody starch were $11~30\mu\textrm{m}$ and those of Superior and Dejima were$ 21~40\mu\textrm{m}$. Blue value, amylose content, relative crystallinity and density of Irish cobbler were the highest, but that of Dejima were the lowest. Water binding capacity, swelling power, transmittance. peak viscosity and breakdown of amylogram of Superior starch were the highest, but that of Irish cobbler starch were the lowest. Gelatinization temperature of DSC of Irish cobbler starch was the highest, but that of Superior starch was the lowest.

• Korean Journal of Food Science and Technology
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• v.36 no.4
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• pp.568-573
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• 2004

Effects of dry heating and pH on pasting, thermal, and textural properties of corn starch containing soy protein isolate (SPI) were investigated. Samples were prepared by drying corn starch dispersions containing 3% SPI at $40^{\circ}C$ (unheated sample) or additionally heating dried mixtures at $130^{\circ}C$ (heated sample). Pasting properties of starch samples and textural properties of starch gels were measured using Rapid Visco-Analyzer (RVA) and Texture Analyzer (TA), respectively. Effects of SPI addition and dry heating on retrogradation and microstructure of gel samples were investigated using DSC and SEM, respectively. Pasting viscosity of dry-heated samples was significantly higher than that of unheated samples, and at pH 8 compared to pH 6. Dry-heat treatment decreased fracture stress and strain of starch gels containing SPI. No significant effects of dry-heat treatment and pH were observed on retrogradation of starch gels. Addition of SPI retarded starch retrogradation and modified starch gel properties with increased nutritional value. Dry-heat treatment with SPI could be possible method for starch modification.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.385-391
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• 2006

Physicochemical properties of hydroxypropylated waxy rice starches were investigated to reduce steeping-time of yukwa (Korean oil-puffed rice snack) processing. Swelling power of hydroxypropylated waxy rice starch increased at relatively higher temperature $(60^{\circ}C)$ than native waxy rice starch $(70^{\circ}C)$. Solubility of hydroxypropylated waxy rice starches increased with increasing propylene oxide content. Pasting temperature $(66.3-66.9^{\circ}C)$ and peak viscosity (216-232 RVU) of hydroxypropylated waxy rice starch were higher than those of native starch (179 RVU) and increased with increasing propylene oxide content. DSC thermal transitions of hydroxypropylated waxy rice starches shifted toward higher temperature. Amylopectin melting enthalpy of hydroxypropylated waxy rice starch (8.4-9.2 J/g) was similar to native starch (9.0 J/g). X-ray diffraction patterns of native and hydroxypropylated waxy rice starches showed typical A-type pattern with no significant differences between them, suggesting hydroxypropylation only affected amorphous region. Results suggest hydroxypropylated waxy rice starch is not applicable for yukwa due to low puffing efficiency and dark color.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1254-1261
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• 1999

The influence of addition of arrow(Pueraria hirsuta Matsum) root flour and its fractions by ultrafiltration on the flow properties of the rice flour-water systems were investigated. The flow properties of rice flour pastes during cold storage$(5^{\circ}C)$ were measured and the components from arrow root flour responsible for changes of flow properties were screened. Addition of arrow root flour significantly changed the flow properties of rice flour pastes. Permeate fractions by ultrafiltration, representing low molecular weight component fraction, significantly affected the flow property of rice flour paste stored at $5^{\circ}C$. Addition of permeate fraction to rice flour pastes rapidly decreased the consistency index, yield stress and pseudoplasticity, and showed a stability of flow property during storage suggesting the retardation of rice starch retrogradation. Permeate fractions of ultrafiltration were identified as puerarin, daidzein and daidzin known to representive isoflavonoid from arrow root.