• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.436-440
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• 2012

This study was carried out to find optimal rice varieties and selection index for sushi. The suitability tests about appearance and palatability were conducted by 31 professional sushi chefs and the physicochemical and pasting properties of the selected 7 rice varieties (Koshihikari, Dami, Deuraechan, Boramchan, Juanbyeo, Sindongjin and Hopum) of milled and cooked rice were evaluated. According to the adaptability for sushi shape and taste of rice, Hopum and Sindongjin showed more suitable appearance and taste than others. Also, they showed remarkable pasting properties similar to Koshihikari which is widely known as a suitable for sushi. In the relationship between suitability and pasting properties for sushi, peak viscosity and breakdown viscosity showed highly positive correlation, and setback viscosity showed negative correlation. These results suggest that pasting properties can be applied to select the suitable varieties for sushi.

• Korean Journal of Food Science and Technology
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• v.24 no.1
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• pp.70-73
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• 1992

Gelatinization behaviour and gel properties of corn starch modified either by hydroxypropylation only or by cross-linking and hydroxypropylation were investigated. Gelatinization temperature of corn starch decreased greatly by hydroxypropylation, but increased slightly by cross-linking with epichlorohydrin. The treatment of both hydroxypropylation and cross-linking lowered the gelatinization temperature, although it was not significantly different from that of hydroxypropylated corn starch. The swelling power of the corn starch was reduced and gel strength was increased by both modifications. The results suggested that the gelatinization behaviour and gel properties of corn starch could be improved by both cross-linking and hydroxypropylation.

• 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.

• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.57-61
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• 1991

Rheological properties of Tongjinbyeo(Japonica) and Samgangbyeo($J{\times}Indica$) rice starches gelatinized with thermal or alkali solutions were investigated with rotational viscometer(Brabender Viscotron). The two starches showed Bingham pseudoplastics behavior in $4{\sim}8%$ thermal or alkali gelatinized starch solutions. Rheological properties of thermal gelatinized starch solutions were similar between the two varieties. However, alkali gelatinized Samgangbyeo starch solutions showed higher values of yield stress and consistency index than that of Tongjinbyeo starch. The values of pseudoplasticity, yield stress and consistency index were higher in the thermal gelatinized samples than those of in the alkali gelatinized ones.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.1
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• pp.87-92
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• 2005

This study was investigated to examine gelatinization properties of waxy black rice starches. X-ray diffraction patterns in raw starches showed traditional A type of cereals. The crystalline regions of both black rice and Shinsunchalbyeo starches disappeared when temperature increased to $65^{\circ}C$ where the crystalline regions of two starches changed to amorphous ones. Scanning Electron Microscope showed that granule type of Shinsunchalbyeo starch was more collapsed compared to that of black rice starch heated at 6$0^{\circ}C$. Gelatinization in both samples completed when samples were heated at 63$^{\circ}C$. The results by Differential Scanning Calorimetry (DSC) revealed that gelatinization patterns were similar in both samples. In Rapid Visco Analyzer examination, there was no difference in peak viscosity, breakdown, final viscosity and setback between Shinsunchalbyeo and waxy black rice starches.

• Proceedings of the Korean Society of Food and Cookery Science Conference
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• 2003.05a
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• pp.90-90
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• 2003

겔상 식품중에서 오미자 젤리는 우리나라의 전통식품으로 활발한 이용이 기대되며, 키토산은 다양한 생리활성을 가지는 것이 알려져 최근 주목받고 있는 첨가물이다. 본 연구에서는 녹두전분, 동부전분, 옥수수전분 등 3종류의 전분에 오미자즙을 첨가하고 1％ chitosan을 첨가한 오미자 젤리를 제조하여 각 전분의 RVA에 의한 점도 특성, 겔의 색도, 이수율 및 파단 특성, TPA 특성 등의 텍스쳐 특성을 조사하고, 관능검사를 실시하였다. RVA 특성치를 보면 키토산의 첨가에 의해 녹두, 옥수수전분의 호화온도는 무첨가와 비교하여 높아져 호화가 지연되었고, 동부전분의 호화온도는 7％, 8％농도에서 낮아졌다. (중략)

• Korean Journal of Food Science and Technology
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• v.16 no.1
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• pp.11-16
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• 1984

Rheological properties of waxy and non-waxy rice starch solutions were evaluated with a narrow gap rotational and Cannon Fenske viscometers. The gelatinized rice starch solutions containing 0.2-1.0% starch displayed pseudoplastic flow behavior. At higher starch level, degree of pseudoplasticity of waxy rice starch solutions increased, while that of non-waxy rice did not changed apparently. The consistency coefficient (K) of non-waxy rice starch solutions increased with increasing gelatinization temperature, but waxy rice starch solutions remained constant, and in alkaline aqueous solutions both of them showed increasing K values. The value of K increased exponentially with an increase in concentration. The effect of the temperature on the viscosity of the solutions followed Arrhenius' type equation, and the activation energies were in the range of 3.675-3.775 kcal/g-mol that were near to that of pure water. The changes of reduced viscosity with concentration were followed Huggin's equation and the values of intrinsic viscosity and interaction coefficient were 0.78-1.59 dl/g and 0.67-2.75, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.9
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• pp.1405-1409
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• 2010

The compositions of fatty acid and amino acid of specialty rice which includes colored rice (Heugjinju, Jeugjinju, Josangheugchalbyeo), flavored rice (Heughyangmi, Hyangmi1), and giant embryo rice (Keunnun) were determined and compared to those of regular rice (Ilpumbyeo, Whaseonchalbyeo). Major fatty acids were linoleic acid (C18:2) and oleic acid (C18:1), which were composed of 75~80% of total fatty acids. Major amino acids were glutamic acid and aspartic acid in most cultivars but Jeugjinju in which cysteine (169.61 nmol) and GABA (129.32 nmol) were the most abundant amino acids. Thermal properties measured by differential scanning calorimeter (DSC) revealed that the enthalpy (${\Delta}H$) for starch gelatinization was the highest in Josangheugchalbyeo and Whaseonchalbyeo. It suggests that the starch structure of waxy rice could be more crystallized compared to non-waxy rice, and also that amylopectin could have more impact on starch gelatinization than amylose. The on-set and complete temperature for starch gelatinization were higher in colored rice of Heugjinju and Jeugjinju, and regular rice of Whateonchalbyeo.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.1
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• pp.17-24
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• 1997

The effects of steeping on the physicochemical and gelatinization characteristics of glutinous rice flour and its starch were studied. Steeping conditions were 1 day at 25"C,7 days at 2iC and 7 days at 35"C. Crude protein, lipid and ash content were decreased br steeping. It was observed with scanning electron microscopy that endosperm cell wall of glutinous rice flour was diminished by steeping. Although morphology of the glutinous rice starch granules was not affected, the size was decreased by steeping. Density and water binding capacity(WBC) of glutinous rice flour and its starch were changed by steeping. X-ray diffraction pattern of glutinous rice starch was A type and was not affected by steeping. Swelling power of glutinous rice flour and its starch was increased but solubility was decreased by steeping. In Brabender amylographic examination, peak viscosity of untreated glutinous rice flour was very low and increased enormously by steeping resulting in the similar Brabender viscosity pattern to its starch. The gelatinization temperature examined by X-ray diffractometry was lowered by steeping. And the degree of gelatinization under the conclusion temperature increased with increasing of steeping Period and temperature.mperature.

• Korean Journal of Food Science and Technology
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• v.52 no.4
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• pp.396-402
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• 2020

In order to investigate the changes in the quality attributes during the storage of dry-milled rice flour, two flour samples were obtained from two rice varieties (Hangaru (HG), Samkwang (SK)). These samples were stored at 4℃ and room temperature, respectively, and we analyzed the initial rice flour moisture content and chemical properties. The changes in the rice flour pasting and quality properties during storage were measured for 12 months. Our results showed that HG exhibited better pasting properties than SK, while the fat acidity of HG rapidly increased at room temperature, resulting in short shelf-life. However, the low-temperature (4℃) storage of dry-milled rice flour could reduce the change in the free fatty acid values of both samples. Therefore, low-temperature storage seems to contribute not only to an increased rice flour shelf-life by reducing the fatty acid value changes but also to a reduction in the changes in pasting properties.