• Journal of the East Asian Society of Dietary Life
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• v.14 no.2
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• pp.145-155
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• 2004

From the cooking data, Japanese rice showed higher water uptake but lower expansion volume, pH and iodine blue value than those of Korean rice. Japanese rice had higher maximum viscosity, breakdown viscosity and pasting temperature but lower final viscosity and setback viscosity than those of Korean rice by RVA analysis. Japanese rice had higher LC (low compression) hardness, U stickiness and HC (high compression) stickiness, LC balance and HC balance, but had lower HC hardness and thickness in the tensipresser data. Also Japanese rice had higher stickiness and balance, and lower hardness from the texturometer analysis. Japanese rice showed higher a cooked taste score than that of the Satake cooked taste machine. The various mean values of Japanese rice after cooking showed better cooking characteristics than the Korean rice. These results might be caused because Japanese rice had a little lower amylose and protein content, but higher tat acidity content.

• 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.

• Korean journal of food and cookery science
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• v.27 no.6
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• pp.745-754
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• 2011

To improve the textural properties of gluten free rice flour based products, the physicochemical and pasting properties of extruded non-waxy rice flours using extruder were investigated. The high yielding Tongil type rice variety, Hanarum was used. Hanarum rice flour was prepared by dry milling from soaked and dried rice grain. The operation conditions of twin screw extruder were 250 rpm of screw speed, $160^{\circ}C$ of barrel temperature, and 24, 27, and 30% of moisture content. Hanarum extruded rice flour (HERF) were lower in crude lipid and ash contents, but higher in crude protein than Hanarum rice flour (HRF). The color values of HERF showed significantly different (p<0.05) with different moisture contents. Water binding capacities, apparent amylose contents, and damaged starch of HERF were higher than those of HRF. Moisture contents affected water binding capacities of HERF. Solubility increased with increasing heating temperature and solubilities of HERF differed significantly (p<0.05). X-ray crystallinity was changed after extrusion cooking and that of HERF showed sharp peaks at $2{\theta}=18-20^{\circ}$. The pasting viscosities of HERF kept lower values (~ 10 RVU) constantly.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.2
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• pp.35-46
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• 2023

The transplanting period limit considering the rice yield in the Dague region, the inland plains of Gyeongsangbuk-do, was estimated to be July 15^th for early and mid-maturing rice and July 5^th for mid-late maturing rice. However, as the transplanting time was delayed, the characteristics of rice starch changed significantly. In the case of early and mid-maturing rice varieties, the starch granule size increased as the transplanting time was delayed; the opposite tendency was observed for mid-late maturing varieties. In all mature rice types, the late transplanting resulted in a longer pasting time and a higher pasting temperature. In addition, the peak viscosity, breakdown, and gelatinization temperature were significantly lowered, the relative crystallinity degree decreased, and the setback was significantly increased. In the case of Ilpum, a mid-late maturing rice variety, the distribution of amylopectin short chains tended to increase when rice was transplanted on June 30^th.

• Korean journal of food and cookery science
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• v.23 no.6
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• pp.908-918
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• 2007

To prepare ready-to-use rice flour as de novo material for processed rice foods, glutinous(W) and normal rice grains (N) were soaked for 1, 8, and 12 hours prior to processing. One half (DG) was air-dried and milled, and the other (WG) was milled and air-dried. General, morphological and pasting properties of the flours (NDG, NWG, WDG, WWG) were compared to those of a control (raw milled rice without soaking). The general compositions of the rice flours varied with soaking. Crude ash was considerably decreased at the beginning of soaking (1 hour). With the soaking, the rice flour, having polygonal shaped particles and a layered surface, acquired particles with smooth edges, which were then uniformly distributed. Additionally, the WG flour was lighter and had a lower ${\Delta}E$ value than the DG flour, due to a higher L and less +b as a result of soaking. Compared to the control, the WBC of the normal rice flour was decreased significantly with soaking, and the WG flour had significantly lower WBCs than the DG flour. Stirring number (SN), an indicator of ${\alpha}-amylase$ activity, was highly and significantly correlated with WBC (r=-0.85, p=0.0001) in the normal rice flour. At $80^{\circ}C$, the SP and solubility of all the soaked rice flours were much higher than those of the control. Positive (r=+0.85, p=0.0001) and negative (r=-0.61, p=0.02) correlations between the SP and solubility of the normal and glutinous rice flours were found, respectively. Using RVA, the pasting temperature of NDG was lower than that of NWG (p<0.0001). The peak viscosities of all the soaked flours were significantly decreased with soaking (p<0.0l), with the highest viscosity in the normal rice flour soaked for 8 hrs. Total setback, indicative of retrogradation, was lower in NDG than in NWG, with the lowest setback at 8 hrs of' soaking. Based on these finding, the NDG flour with 8 hrs of soaking was less damaged, and had a lower total setback and lower pasting temperature, which would make it an appropriate rice flour for commercial mass production.

• Korean Journal of Food Science and Technology
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• v.43 no.4
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• pp.401-406
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• 2011

This study was conducted to investigate the pasting and sensory properties of different commercial rice cultivars. All samples had adequate moisture content, and Gyeonggi Kosihikari had the lowest protein content (6.75%). Apparent quality of head rice ranged from 85.63 to 98.70% and amylose content was 21.51-26.54%. In a rapid visco analyzer examination, pasting temperature of Gyeonggi Kosihikari was the lowest (84.87). Breakdown of Gangwon Oade (43.64 RVU) was lower that of others, indicating the highest pasting stability. The setback of Jeonam Hitomebore was the lowest (81.56 RVU), suggesting slow deterioration. A texture analysis test showed that Gyeonggi Koshihikari had the lowest hardness and Chungnam Samgwang had the highest adhesiveness. Gyeonggi Koshihikari had the highest sensory scores for appearance, flavor, taste, texture and overall acceptability. These results indicate that Gyeonggi Koshihikari is the most adequate rice product among cultivars.

• Applied Biological Chemistry
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• v.49 no.1
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• pp.49-54
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• 2006

Physicochemical properties of cross-linked rice starches were investigated. Swelling power of cross-linked rice starch increased at relatively lower temperature $(60^{\circ}C)$ than native rice starch $(70^{\circ}C)$. Cross-linked rice starch showed lower solubility $(1.7{\sim}6.1%)$ than native rice starch $(2.2{\sim}13.8%)$ and solubility is not significantly different with the amount of phosphorus oxychloride. Pasting temperature $(69.2{\sim}70.6^{\circ}C)$ and peak viscosity $(2,874{\sim}3,175\;cp)$ of cross-linked rice starch were lower than native starch $(71.6^{\circ}C,\;3,976\;cp)$, but holding strength $(2,177{\sim}2,708\;cp)$ and final viscosity $(3,424{\sim}3,826 \;cp)$ of cross-linked rice starch were higher than native starch (1,000 cp, 2,312 cp). DSC thermal transitions of cross-linked rice starches were shifted to a lower temperature than native rice starch but there was no significant difference in gelatinization enthalpy between native and cross-linked rice starches. X-ray diffraction pattern of both native and cross-linked rice starches showed typical A-type crystal indicating that cross-linking had not affected the crystalline region of starch.

• The Korean Journal of Community Living Science
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• v.23 no.4
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• pp.537-552
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• 2012

This study was conducted to investigate the quality characteristics of cooked rice with cereals frequently consumed in Korea by blending ratio. Seven kinds of cereals, white rice, glutinous barley, brown rice, black rice, glutinous rice, glutinous foxtail millet and proso millet, were chosen for the study. According to the results from rapid viscosity analyzer, glutinous barley had the lowest pasting temperature($66.55^{\circ}C$) and black rice had the highest values in the peak(231.77 RVU), trough(162.25 RVU), final viscosity(295.81 RVU) and set back(64.05 RVU)(p<0.05). Water absorption rate by soaking time for black rice and brown rice was increased only 18.77% and 14.57%, respectively, even after 120 minutes, whereas those of other cereals were increased up to 20.28~39.32% after 50 minutes. The pasting characteristics of white rice blended with cereals tended to be lower than white rice in the peak, trough, and final viscosity. Textural property of cooked white rice blended with black rice, brown rice, and glutinous foxtail millet showed a significantly higher value for hardness than that of cooked white rice only(p<0.05). The most preferred blending ratio of the respective cereals was 25% for glutinous barley, 10% for black rice, brown rice and proso millet, and 5% for glutinous foxtail millet and glutinous rice in the sensory evaluation for overall quality, but there were no significant differences except glutinous barley, brown rice and glutinous foxtail millet.

• 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 $90^{\circ}C$.

• 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.