• Journal of the East Asian Society of Dietary Life
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• v.22 no.6
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• pp.802-811
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• 2012

This study was conducted to test the characteristics of dough made with rice flour for preparation of steamed cakes containing rice flour. We used a RVA (Rapid Visco Analyser), farinogram and alveogram to analyze cake flour and mixed powder containing 10, 20, and 30% rice flour for the water activity, texture, and, color changes after different storage periods. We found that rice flour inhibited starch aging, and that gluten free rice flour made the cakes more delicate. However, steamed cakes containing rice flour were harder than wheat cakes during storage. Because the cake was steamed, it had more moisture and was softer than cakes baked in an oven. The steamed cake prepared with rice flour became brighter than the control. The results of the consumer acceptance test and sensory characteristics showed that the steamed cake containing 20% rice flour obtained the highest score, indicating that this is the most appropriate level for making steamed cakes.

• The Korean Journal of Food And Nutrition
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• v.21 no.4
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• pp.463-469
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• 2008

To make of basic date for the progressive global brand of Korean rice, we compared with characteristics of Calrose and two Korean rice cultivar, Chucheongbyeo(medium-late maturing cultivar) and Odaebyeo(early-maturing cultivar). General characteristics of rice, pasting property of rice flour by Rapid visco Analyser, determination of optimal ratio of water to rice for cooking by electric and pressure cooker and eating quality(sensory evaluation) of Calrose with that of Korean rice cooked at the optimal cooking conditions were measured. One kernel length of Calrose, Chucheongbyeo and Odaebyeo were 6.00, 4.73 and 5.22 mm, respectively. Calrose showed higher viscosity(195 RVU) in all parameters than Korean rices(Chucheongbyeo 176 RVU, Odaebyeo 178 RVU), of which the values were similar. These data imply that the properties of starch of Calrose may be different from that of Korean rice. In general, it is agreed, in Korea and Japan, that the balance of hardness and stickiness of cooked rice is very important. However, stickiness and overall eating quality for cooked Calrose was significantly poorer than Korean rices. Cooked Calrose did not significantly different in hardness, stickiness and overall eating quality compared with those of Korean rices. Calrose cooked with the ratio of water to rice of 1.4 with electric cooker was less sticky than Korean rices and thus was poorer in eating quality compared with Korean counterparts. Calrose cooked with the ratio of water to rice of 1.3 with pressure cooker had the same eating quality with Korean rices.

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.762-769
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• 2012

In order to study the cooking characteristics of four rice cultivars of Seolhyangchal, Baegjinju, Ilpum and Haiami, we investigated the relationship between the textures of cooked rice and their physicochemical properties. Different levels in grain weight. length/width ratio and amylose content were observed among the four rice cultivars. There was no significant difference in the amylopectin chain length distribution among the cultivars. Water absorptions of rice grains during soaking were completed between 30 and 40 min, with Haiami showing the slowest absorption. Significant differences in the viscosity properties of rice flour were found by a Rapid Visco Analyser. Baegjinju with low amylose content had the highest viscosity in paste breakdown. According to the DSC results of rice starches, there were significant differences in the onset, peak and conclusion temperatures of the endothermic peak. Gelatinization enthalpy showed energy content changes between 4.20 and 6.97 J/g, with the lowest change in Haiami. Texture properties of cooked rice were assessed using a Texture Analyzer, which showed that the hardness of cooked rice was decreased with soaking than without soaking. However, this finding was not applicable for Haiami rice.

• Korean journal of food and cookery science
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• v.13 no.5
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• pp.627-634
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• 1997

The purpose of this study is to examine the effect of protein content on the physicochemical properties, gelatinized characteristics and textural properties of cowpea precipitate gels stored for 24 hrs and 48 hrs at room temperature. The contents of protein, total fat, and ash ranged from 0.35%∼1.38%, 0.54%∼0.64%, and 0.21%∼0.25%, respectively. The X-ray diffraction patterns were all Ca-type, showing no difference according to the protein content. Protein content did not make any difference in the blue values of cowpea precipitate. The blue value of cowpea precipitate powder as protein content was decreased. The water-binding capacity of cowpea precipitate powder increased as the protein content increased. Swelling power and solubility of cowpea precipitate powder increased as protein content decreased. The transmittance of cowpea precipitate powder was not different according to the protein content. The initial pasting temperature of cowpea precipitate powder by differential scanning calorimetry (DSC) and rapid visco analyser (RVA) showed no differences according to the protein content. In sensory evaluation, the color and clarity of cowpea precipitate gels stored for 24 hrs and 48 hrs at room temperature as the protein content increased, and the hardness, cohesiveness, springiness, acceptability were greater when the gels were stored for 48 hrs. Instrumental analyses using a rheometer showed that the hardness, gumminess, and chewiness of cowpea precipitate gels stored for 24 hrs, which was increased as the high protein content increased. For the gels stored for 48 hrs, all other factors are significantly different except cohesiveness as the protein content increased.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.952-958
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• 2004

Effects of normal (non-waxy) and waxy millet flours on properties of sponge cake were examined. Total dietary fiber contents of normal and waxy millets were 5.04 and 5.12%, respectively, while that of soft wheat flour was 2.23%. Alkaline water retention capacity value generally increased with addition of normal and waxy millet flours, whereas peak, minimum, and final viscosities decreased. Mixing time and mixing height decreased with addition of millet flour. Lightness of cake crust increased with addition of normal millet flour, whereas it decreased with addition of waxy millet flour, tightness of cake crumb decreased as the amount of normal and waxy millet flours increased. Increasing proportions of normal and waxy millet flours resulted in significantly decreased loaf volume. Replacement of 10% wheat flour by both normal and waxy millet flours did not significantly affect characteristics of sponge cake, but addition of more than 20% millet flour resulted in significant differences in quality characteristics.

• Korean journal of food and cookery science
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• v.15 no.2
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• pp.127-132
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• 1999

Dried noodles (somyon) were stored for 7 months at 25, 35 and 45$^{\circ}C$, and changes of water activity, amylograms and color of dried noodle at 4 week intervals were comparatively analyzed. The water activities during storage period were 0.43∼0.56 at all storage temperature. The breakdown of dried noodle by RVA(rapid visco analyser) increased as storage period increased. Color difference ($\Delta$E) was chosen for quality index due to the highest correlation coefficient between sensory score and color difference. The shelf-life of dried noodle was estimated from change of color, which was linearly increased as the storage period increased. The activation energy and Q$\sub$10/ value for color difference were 75.21 kJ/mol and 2.76 at 25$^{\circ}C$, respectively. Shelf-life of dried noodle at 25 were 27.9 months, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.3
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• pp.430-435
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• 2012

This study was carried out to investigate the rheological effects of black garlic extracts on the bread dough. 0, 5, 10 and 15% of black garlic extracts were added in the bread flour. Falling number, RVA (Rapid visco analyser), farinograph and alveograph were analyzed. Falling number was lowered by increasing the amount of the extract added in the wheat flour. The pasting characteristics of the dough by RVA, value of pasting temperature, peak viscosity, holding strength, final viscosity, break down and set back were increased compared to the control. In the Farinograph analysis, the consistency and the water absorption ratio were elevated with the increase of the extract added. However, the rapid decrease of stability and the time to breakdown values were observed by increasing the extract addition amount compared to the control. However the mixing tolerance index (MTI) was rapidly increased as the amount of the extract addition was increased, and the highest farinogram quality number was observed in the control. Through the alveograph analysis, $P_{max}$ value was found to show the highest value in the control, while the L and G values were higher but W values was lowered in the dough with added 15% black garlic extract. As a result of the analysis, there was no significant bad effect until 5% of black garlic extracts was added to the bread dough.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.4
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• pp.441-451
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• 2019

This study was conducted to investigate the crop characteristics of 181 sweetpotato germplasms collected from Korea and overseas. The longest shoot vine length was observed in IT232211 (354.8 cm) and the shortest shoot vine length was observed in IT232185 (32 cm). The maximum numbers of shoot branches and nodes were produced by IT232091 (23.0) and IT232174 (67.8), respectively. Differences in Rapid Visco Analyser profiles were observed for pasting parameters such peak, trough, final, breakdown, and setback viscosities; and pasting temperature. The peak and breakdown viscosities were highest in IT232050 and IT232010, at 338.3 and 207.2 Rapid Visco Unit (RVU), respectively. The trough viscosity was lowest in IT232019 at 103.8 RVU. IT232101 had the highest final viscosity (284.6 RVU), and IT232192 had the highest setback viscosity (81.7 RVU). IT232197 had the highest pasting temperature at 86.8℃, and that of IT232134 was lowest at 72.7℃. To evaluate functional substance content, we analyzed 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and total polyphenol content. The highest frequency proportion of starch was in the 10%-15% range (50.8% of the plants), followed by the 5%-10% range (38.1% of the germplasms). Sugar content ranged from 13.5 to 33.3% (23.2% on average); the highest frequency proportion of sugar was in the 20%-25% range (56.9% of the germplasms), followed by the 25%-30% range (25.4% of the germplasms). The highest frequency proportion of water was in the 70%-80% range (52.5% of the germplasms), followed by the 60%-70% range (44.2% of the germplasms). Our results provide basic data for the selection of useful resources and for the development of new sweetpotato varieties.

• Korean Journal of Food Science and Technology
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• v.39 no.1
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• pp.33-38
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• 2007

The peak time, peak height, width at peak, and the width at 8 min of Mixograph increased as the amount of sodium chloride in yellow alkaline noodle sheet was increased. The peak time of the Mixograph duration increased almost twice when 0.5% sodium carbonate was added to yellow alkaline noodle sheet, but decreased when the amount of sodium carbonate was above 0.5%. The peak height decreased as the amount of sodium carbonate increased. Protein content and sedimentation values showed positive correlations with the Mixograph peak height, width at peak, and width at 8min. The pasting temperature, peak viscosity, minimum viscosity, and final viscosity increased as the amount of sodium chloride in yellow alkaline noodle sheets was increased for all wheat flours. The peak viscosity, minimum viscosity, and final viscosity also increased as the amount of sodium carbonate increased. The pasting temperature showed a positive correlation with the water retention capacity and the alkaline water retention capacity.

• Food Science and Preservation
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• v.23 no.2
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• pp.194-203
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• 2016

The purpose of this study was to investigate the properties of tteok prepared from white (Samkwang) and brown rice (Heugseol, Heugjinju). The moisture and crude protein contents of rice were 14.89~17.15% and 4.79~6.81%, respectively. The crude lipid and crude ash contents of rice were 0.48~2.66% and 0.39~1.60%, respectively. The water binding capacity of Heugjinju (141.97%) was higher than those of other rice flours. As the soaking time increased, water absorption ability was in the order of Samkwang > Heugseol > Heugjinju. Using a rapid visco analyser (RVA), the initial pasting temperature of Heugseol was the highest, and the peak viscosities of Heugseol were higher than those of other rice flours. The quality characteristics of Tteokbokki tteok were assessed after its preparation by adding different amounts of Heugseol and Heugjinju (0, 5, 10, and 20%, w/w) content. The textural properties (hardness), of Heugseol and Heugseol measured using a texture analyzer, were greater than those of the control. Sensory preference tests revealed that 10% Heugseol and, 10% Heugjinju had the highest scores in appearance, color, and overall acceptability. The sensory test results revealed that Tteokbokki tteok prepared by addition of 10% added brown rice was the best.