• Korean Journal of Food Science and Technology
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• v.49 no.4
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• pp.360-368
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• 2017

The objective of this research was to elucidate the physicochemical, structural, pasting and rheological properties of potato starch isolated from a foreign potato cultivar ('Atlantic') and new domestic potato cultivars ('Goun', 'Sebong', and 'Jinsun'). Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and one-dimensional nuclear magnetic resonance (1D NMR) showed that the structural properties of potato starch did not vary significantly with cultivars. RVA analysis demonstrated that the 'Atlantic' starch had the highest breakdown viscosity among all potato starches. In steady shear rheological analysis, all potato starch dispersions showed shear-thinning behaviors (n =0.63-0.72) at $25^{\circ}C$. The highest apparent viscosity (${\eta}_{a,5}$), consistency index (K), and yield stress (${\sigma}_{oc}$) were observed in the 'Goun' starch dispersion. In dynamic shear rheological analysis, storage modulus (G') and loss modulus (G") values of new domestic potato starch dispersions were higher than those of the 'Atlantic' starch dispersion.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1291-1297
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• 2000

Particle size distribution, pasting properties by Rapid Visco Analyser, and textural properties of acorn, mungbean and buckwheat starches, which are the basic raw materials for mook, are compared. The major particle size of mungbean starch was $10{\sim}30$ micron, whereas acorn and buckwheat starches were $5{\sim}20$ micron. At the same starch concentration, mungbean starch had the highest peak viscosity, breakdown and setback. Acorn starch showed the lowest peak viscosity and breakdown. The peak viscosity of buckwheat starch was close to that of mungbean, however the trough and final viscosity were comparable to those of acorn starch. At the same peak viscosity, mungbean starch showed the lowest trough and final viscosity and the highest breakdown and setback. Acorn starch was differentiated from buckwheat starch in that the former had the higher value of setback. The textural properties of mungbean starch gel were significantly different from others. The texture of gels from acorn and buckwheat starches revealed that only the hardness and gumminess were different each other. The hardness of starch gels were negatively correlated with trough and final viscosity, and positively correlated with setback.

• Food Science and Preservation
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• v.18 no.3
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• pp.271-278
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• 2011

Considering the importance of cassava as food crops in humid tropics, the effect of feed moisture (20, 25%) and barrel temperature (110, $130^{\circ}C$) on physical properties (piece density, expansion, mechanical properties, color, water solubility index, water absorption index) and pasting properties of extruded cassava starch was investigated. The feed moisture used during extrusion processing had a significant effect on extrudates SME input, specific length and piece density at (p<0.05) while effect on cross-sectional expansion index, apparent elastic modulus and breaking strength in bending shown significantly at p<0.1. Furthermore, the interaction effect of feed moisture and barrel temperature gave a significantly affected the SME input and piece density (p<0.1), specific length (p<0.05) and on redness (p<0.01). The increase in water injection rate led to increase in piece density, apparent elastic modulus, breaking strength in bending, cold peak viscosity, breakdown and final viscosity and decrease in cross-sectional expansion index and specific length. It was found that the extrusion cooking process did not affect the value of color L, color b, water solubility index and water absorption index. Thus, the results of this study can be useful to some extent in developing extruded cassava starch as human and animal feeds.

• Journal of the Korean Mathematical Society
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• v.45 no.4
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• pp.1007-1025
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• 2008

We will describe a way to construct Ford domains of cusped hyperbolic 3-manifolds on maximal cusp diagrams and compute fundamental groups using face pairing maps as generators and Cannon-Floyd-Parry's edge cycles as relations. We also describe explicitly a cutting and pasting alteration to reduce the number of faces on the bottom region of Ford domains. We expect that our analysis of Ford domains will be useful on other future research.

• Proceedings of the Korean Society of Crop Science Conference
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• 2003.10a
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• pp.232-233
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• 2003

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.3
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• pp.186-190
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• 2005

This experiment was conducted to collect the basic information on the varietal diversity in amylogram properties of 3 different rice sub-species under tropical conditions in IRRI 2001 wet season based upon correlation and principal component analysis. The peak viscosity and breakdown property of Tongil type, i.e.; temperate Indica species showed higher similarity with Japonica type species rather than typical Indica and tropical japonica types. The amylogram properties such as final viscosity, pasting consistency and setback of Tongil type varieties were lower than those of typical Indica and tropical japonica types. The peak viscosity showed positive correlation with trough, while the breakdown showed negative correlation with setback in all tested 3 rice subspecies. The first principal component was applicable to increase the gelatinization temperature, final viscosity, pasting consistency and setback, and applicable to decrease the peak viscosity and breakdown. Varietal classification by the principal component score of each pedigree could be applied to the interpretation of the community by the scatter diagram for the amylogram properties to the different sub-species of rice at IRRI conditions.

• Applied Biological Chemistry
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• v.30 no.1
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• pp.24-30
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• 1987

starches, isolated from Japonica and nonwaxy rites, were analyzed fur gelatinization characteristics. Amylose contents of Taebaeg and Sangpung starch were 16 and 17%, respectively. The portion of large-sized particles was more pronounced in the case of Sangpung starch. Swelling power and solubility increased according to the rise in gelatinization temperature. The decrease of pasting temperature according to the incense in starch concentration in Sangpung starch was higher than that of Taebaeg starch. Most of the increase in light penetration was accomplished between 85 and $90^{\circ}C$. Gelatinization reactions of Taebaeg and Sangpung starch appeared as 2 different stages up to the gelatinization temperature of $90^{\circ}C$.

• The Korean Journal of Food And Nutrition
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• v.20 no.4
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• pp.399-405
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• 2007

The quality characteristics of breads made by adding levels of 30%, 60%, and 100% aloe gel were investigated. The 60% aloe gel sample had a larger dough volume than the control dough. Also, the loaf volume and specific volume of the bread made with 60% aloe gel were larger than those of the control bread. The pasting temperature increased gradually with the increasing amounts of substituted aloe gel as compared to wheat flour with water added$(66.5{\pm}12^{\circ}C)$; the wheat flour with 100% aloe gel had a pasting temperature of $90.7{\pm}1.1^{\circ}C$. Peak viscosity decreased gradually with increasing amounts of aloe gel when compared to the wheat flour with water added. Setback also was decreased gradually with the increasing amounts of aloe gel as compared to the wheat flour with added water. From the setback decrease it is suggested that the aloe controlled retrogradation of the bread during short-term storage. The crumb color of the bread made with the aloe gel was not significantly different to that of the control bread, and the color of the crumb was yellow-white. Bread hardness decreased gradually with increasing amounts of the substituted aloe gel. However, bread gumminess and chewiness increased gradually with increasing amounts of aloe gel. The springiness of the bread made with 100% aloe gel was lower than that of the control bread. With regard to flavor and taste, the bread made with 100% aloe gel produced a green-like odor and had a bitter taste. The mouth feel of the breads made with aloe gel was considered soft and moist. The overall acceptabilities of the breads made with 30% and 60% aloe gel were not significantly different from the control bread, but the bread made with 100% aloe gel had a green smell and bitter taste. Yet accordingly, the results indicate that functional and health products with improved quality could be developed by adding aloe gel to breads and cakes.

• Korean journal of food and cookery science
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• v.22 no.2 s.92
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• pp.193-203
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• 2006

The quality characteristics of cookies containing black rice flour, which has a greater variety of functional components than wheat flour, were studied. The results of the pasting properties shows that the inclusion of black rice flour to the wheat flour-mixture did not affect the pasting temperature but increased the enthalpy, indicating that more energy is needed for the starch gelatinization. The total dietary fiber and total polyphenol content increased and the cookies color became darker and deeper with increasing black rice flour content. According to the results from TA on texture, the hardness decreased and the crispness increased significantly (both, p<0.001) with increasing black rice flour content. From the acceptance test, the appearance, aroma and texture of the cookies with added black rice flour were significantly (p<0.001) lower than those of the wheat flour cookies. However, the taste and overall acceptance of the cookies with added black rice (lour did not differ significantly from those of the wheat flour cookies. According to the results from the sensory evaluation, the aroma, black rice flavor, crispness, graininess and color(gray-violet) of the cookies increased significantly(p<0.001) with increasing black rice flour content and those of the cookies with 30% black rice flour had the highest values among the cookies which weren't significantly different from those of the cookies with 20% black rice flour. From the above results, the optimal ratio for the addition of black rice flour to the cookies was 10% from the viewpoint of the sensory evaluation and functional components.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.185-185
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• 2017

In previously study, we evaluated seed germination for longevity derived from a cross between 'Ilmi' and 'Dharial', a weed rice collected in Bangladesh. The strong germination trait originated from 'Dharial' was incorporated into 'Ilmi', through backcross method. The germination ratio was evaluated after two years of room temperature storage conditions. A high germination ratio of 80.5% in donor plant of 'Dharial' and 77.3% in an introgression lines was observed based on the two years of storage while the recurrent japonica cultivars, 'Ilmi' was failed in germination. In this study, we investigate changes in physicochemical properties of 'Ilmi' and introgression lines (ILs) stored at room temperature. We analyzed germination rate, texture of cooked rice, toyo glossiness value, pasting properties, amylose content, protein content and ${\alpha}-amylase$ content of 'Ilmi' and 5 introgressions every 4 months on the room temperature condition. Seed germinations were decreased by storage periods. Three ILs germination rate was slowly decreased more than 'Ilmi' and 2 another ILs after 4 months. Toyo glossiness value of 'Ilmi' and three ILs were no difference, but, 2 ILs gradually decreased every 4 months at storage periods. Pasting properties were affected by storage temperatures and periods of 'Ilmi' and ILs. The increase at breakdown was observed but setback was decreased by storage periods. Amylose content and protein content were no significant difference at storage periods, respectively. The ${\alpha}-amylase$ content was gradually increased during the storage periods. The introgression line could be useful to increase longevity and maintain quality during storage of japonica rice seed.