• 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.

• 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.

• 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 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1277-1282
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• 2013

The effects of pregelatinized rice flour (PRF) as an additive on the textural properties of rice cookies were investigated in this study. PRF was used at 10, 20, 30, 40, 50, and 60% per 100 g of rice flour. The hardness of dough and cookies, as measured by a texture analyzer, increased upon the addition of PRF. In contrast, the moisture content of the dough and cookies decreased upon the addition of PRF. The L value of the dough and cookies decreased upon the addition of PRF, whereas the a value increased upon the addition of PRF. The bulk density of the cookies increased upon the addition of PRF. In addition, the spreadability of the cookies was lower than the control. In the sensory evaluation, rice cookies with 50% PRF showed the highest scores for hardness, brittleness, softness, and moisture. Rice cookies with 60% PRF showed the highest scores for sandiness. Our results suggest that the texture of the rice cookies can be improved by adding PRF.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.10
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• pp.1467-1475
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• 2016

To make soft and less stale bread, various amounts of gelatinized wheat flour dough were added for making pan bread. In the dough process, higher gelatinized wheat flour dough showed higher consistency and dough development time but a lower dough stability time. Expansion during fermentation represented the highest value upon addition of 10% gelatinized wheat flour dough (GWFD), and this value decreased with increasing amount of gelatinized wheat flour dough. Volume of bread was the highest in the control and lowest in 30% GWFD, and there was no difference between 10% GWFD and 20% GWFD. Moisture contents of bread made with various amounts of gelatinized wheat flour dough increased with increasing gelatinized wheat flour dough amount. Color values of bread made with various gelatinized wheat flour dough were not significantly different. Chewiness, brittleness, and hardness of bread made with control and 10% GWFD showed low values, whereas bread made with 20% GWFD and 30% GWFD showed high values. During storage, chewiness, brittleness, and hardness increased with increasing storage period in whole breads, whereas breads made with 10% GWFD showed the lowest increasing rate. In the sensory strength test, chewy texture increased upon addition of gelatinized wheat flour dough. In the consumer acceptance test, 10% GWFD showed the most overall acceptance. In conclusion, bread made with 10% gelatinized wheat flour dough is desirable for increasing softness and decreasing bread staling.

• Applied Biological Chemistry
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• v.34 no.4
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• pp.360-365
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• 1991

Rheological properties of Shinsunchalbyeo(Japonica) and $Hangangchalbyeo(J{\times}Indica)$ waxy-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. The shear stress of Hangangchalbyeo starch solution gelatinized with thermal or alkali showed higher values than that of Shinsunchalbyeo starch and the difference of the two varieties gelatinized with alkali showed higher values than that gelatinized with thermal. Consistency index and yield stress values of Hangangchalbyeo starch showed higher than that of Shinsunchalbyeo starch in the two gelatinized methods and the difference of the two varieties gelatinized with alkali showed higher values. And it was higher that the deffendence of consistency index on starch concentration and initial starch concentration of yield stress in the alkali gelatinized samples than those of in the thermal gelatinized ones.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.742-748
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• 1989

Rheological properties of gelatinized millet starch dispersions were evaluated. Gelatinized nonwaxy and waxy millet starch dispersion were typical pseudoplastic fluids. At constant shear rate, gelatinized waxy millet starch dispersion showed higher shear stress than nonwaxy millet starch dispersion. Flow behaviours of gelatinized nonwaxy and waxy millet starch dispersion were well fitted to Herschel-Bulkley equation and flow behaviour index (n) and consistency index (K) were strongly concentration dependent. There was a linear relationship between concentration of gelatinized starch dispersion and square root of yield stress. The concentrations of gelatinized nonwaxy and waxy millet starch dispersion where yield stresses become zero were estimated as 2.19 and 1.69%, respectively. Pseudoplastic constant (m) approaches to a constant value in each type of millet starch when the concentration of gelatinized starch dispersion was increased. As the measuring temperatures increase, n value was increased, whereas, K value was decreased. The activation energies of gelatinized nonwaxy and waxy millet starch dispersion were 2.89 and 3.18kcal/mol, respectively.