• Food Science and Preservation
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• v.15 no.3
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• pp.390-395
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• 2008

The rheological properties of dough made with 0% 1 % 2% or 3% Corni fructus flour were investigated Rapid Visco Analyzer (RVA) analysis showed that the initial pasting temperature increased with increasing Corni fructusflour content, while the peak viscosity decreased. The water absorption, stability, development time, elasticity and valorimeter value of the dough, as determined using a farinograph and alveograph, decreased with increasing amounts of Corni fructusflour, while weakness increased. The extensibility, fermented volume and consistency of the dough increased gradually with increasing Corni fructus flour content. These results indicate that the addition of Corni fructus flour affects the rheological properties of bread.

• Journal of Korea Water Resources Association
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• v.43 no.4
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• pp.325-336
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• 2010

This study presents the alteration of flow regime by effects of dams and water use in the Geum River Basin. The surface water use rate and the Impounded Runoff (IR) index were examined to assess the pressure indicators of the flow alteration. We applied the flow duration curve, flow regime coefficient, flood and low-flow frequency analysis as well as Range of Variability Approach (RVA) to investigate the quantitative changes in natural flow regimes. The results indicate that the high flow decreased and low flow increased respectively compared to the natural flow regimes at eight gauging stations. The Geum river is regulated by 139 dams and reservoirs storing 24% of the annual mean discharge and has high surface water use rate of 36%. These indicators are main pressure factors to alter flow regimes.

• The Korean Journal of Food And Nutrition
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• v.30 no.4
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• pp.635-643
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• 2017

The properties of rice were studied, and 8 rice flour cultivars were used to study the effect of particle size on the physicochemical properties, color value, RVA viscosities, water absorption index (WAI), and water solubility index (WSI) of rice flours. The mean particle size by the 3 particle size classification of 150 mesh, 200 mesh, and 250 mesh was, $90.75{\mu}m$, $60.73{\mu}m$, $39.94{\mu}m$, respectively. Thai rice had the highest amylose content and Samkwang rice had the lowest amylose content. Protein content of rice flours prepared was decreased as the particle size of rice flour decreased. In terms of color values, the L-value and the a-value of rice flour were increased as the particle size of rice flours decreased, while the b-value was decreased as the particle size of rice flours decreased. Using a rapid visco analyzer (RVA), the initial pasting temperature of Thai rice cultivar was found to be the highest; the peak viscosities of Sunpum cultivar and Misomi cultivar, and Samkwang rice were higher than those of other rice flours. The water absorption index and water solubility index were increased as the particle size of rice flour decreased. In order to use processed rice flour for the development of processed foods, proper characteristics of the cultivars and particle size should be considered.

• Korean Journal of Food Science and Technology
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• v.39 no.5
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• pp.534-540
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• 2007

In this study, waxy rice starch was chemically modified using phosphorous oxychloride ($POCl_3$, 0.002-0.008%). Then the physicochemical properties of resulting cross-linked waxy rice starches were investigated in order to reduce the steeping time of Yukwa (a Korean oil-puffed rice snack) processing. The swelling powers of the cross-linked waxy rice starch samples were higher than the native waxy rice starch at temperatures above $60^{\circ}C$, and their increases were proportional to the $POCl_3$, concentration. The solubility of the cross-linked waxy rice starch was lower (1.6-3.4%) than the native waxy rice starch (2.7-6.1%). However, the moisture sorption isotherm of the cross-linked waxy rice starch was not significantly different from the native waxy rice starch. The rapid visco analyze. (RVA) pasting temperatures $(65.4-67^{\circ}C)$ of the cross-linked waxy rice starch were lower than those of the native starch $(67^{\circ}C)$. The RVA peak viscosities (287-337 RVU) of the cross-linked waxy rice starch were higher than that of native starch (179 rapid visco units (RVU)), and increased with increasing $POCl_3$ concentration. For the differential scornning calorimeter thermal characteristics, although Tc shifted toward higher temperatures with cross-linking, the To, Tp, and amylopectiin melting enthalpy of the cross-linked waxy rice starch showed no differences compared to the native waxy rice starch. The X-ray diffraction patterns of both the native and cross-linked waxy rice starches showed typical A-type crystal patterns, suggesting that cross-linking mainly occurs in the amorphous regions of starch granules. Therefore, the cross-linking reaction did not change the crystalline region, but altered the amorphous region of the waxy rice starch molecules, resulting in changes of solubility and RVA pasting properties in the cross-linked waxy rice starch. In summary, since cross-linked waxy rice starch has a high puffing efficiency and no browning reaction, it may be applicable for Yukwa processing without a long steeping process.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.15 no.1
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• pp.113-125
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• 2004

Effect of microwave radiation on physico-chemical properties of cor'n starches was studied. Waxy com, com and high amylose com starches of varying moisture content(20～35%) were subjected to microwave processing(2450MHz) at $120^{\circ}$ and the experimental starch samples were examined by a X-ray diffractometry, rapid viscosity analyzer(RVA) and. with the samples in temperature was observed and the peaks of high amylose com starches at $2^{\circ}$=5.0, 15.0 and $23.0^{\circ}$, were disappeared indicating the melting of crystallines while those of com and waxy com had not changed. A change in gelatinization pattern was observed in the case of corn starches from type A with nearly no peak-viscosity and breakdown to type C. Except a decreased viscosity, no change was observed in those of waxy com starches.

• 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.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.1
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• pp.53-59
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• 2011

The purpose of this study was to investigate the properties of frozen cookies containing buckwheat flour. Buckwheat flour was added to cake flour bases at concentrations of 3%, 6%, and 9%. Falling numbers, RVA (rapid visco analyzer) increased with the addition of buckwheat flour, whereas initial pasting temperature decreased. The set back value, which is a prediction of retrogradation, did not show any significant difference. The alveographic P values of the treatment were lower than that of the Control. In the farinogram test, water absorption increased upon the addition of buckwheat flour, whereas stability and farinogram quality number decreased. In conclusion, the addition of 6% buckwheat flour is recommended to obtain the optimal volume of frozen cookies.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.2
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• pp.198-202
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• 2009

The starch properties of two chinese yams were evaluated in this study. Amylose content ranged 13.5% to 19.3%. The swelling power of starches varied 10.98% to 11.43%. Water binding capacity in chinese yam starches ranged 93.46% to 107.21%, high WBC was observed in Ma 1. The onset temperature (To) of two chinese yam starches ranged 62.9 to $75.0^{\circ}C$, peak temperature (Tp) ranged 76.2 to $84.7^{\circ}C$. The PHI(peak height index) was about 4-fold higher in Anwon cultivar than in Ma 1 cultivar. SEM revealed that starches has a presence of large oval or spherical to small irregular-shape granules. Starch granule size ranged 15.23 to 15.52 ${\mu}m$, showing a typical C-type X-ray pattern.

• The Korean Journal of Community Living Science
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• v.26 no.1
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• pp.135-143
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• 2015

This study investigates the rheological properties of bread containing lotus leaf powder, added to the bread bases at 1%, 2%, and 3% concentrations. Physical properties of bread with lotus leaf powder were tested using the rapid viscoanalyzer (RVA), a farinogram, an alveogram, and a rheofermentometer. The initial pasting temperature increased with an increase in lotus leaf powder, whereas peak viscosity and, the peak time decreased. According to the farinogram test, consistency and water absorption increased with an increase in the ratio of lotus leaf powder. The p value of the alveogram increased with an increase in lotus leaf powder, whereas L and G values decreased. The fermentation time of the dough increased with an increase in the ratio of lotus leaf powder. The results suggest the potential development of bread containing functional ingredient such as lotus leaf powder based on the rheological properties identified in this study.

• Food Science and Biotechnology
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• v.15 no.6
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• pp.860-865
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• 2006

The quality parameters of sponge cake supplemented with soy protein concentrate (SPC) were evaluated. The addition of SPC to wheat flour increased the protein content and alkaline water retention value, but decreased the sedimentation value. Protein content had a positive correlation with the alkaline water retention value, and a negative correlation with the sedintentation value. The higher the concentration of SPC, the higher the RVA pasting temperature and the lower the viscosity. Increasing the level of SPC in flour led to a decrease in mixogram peak time, whereas peak height, width at peak, and width at 8 min progressively increased. As the amount of SPC increased in the formulation, the pH and specific gravity of cake batter increased, whereas the volume and specific volume of sponge cake decreased. The total isoflavones content in SPC increased after heat treatment. The hardness, gumminess, and chewiness increased progressively in accordance with increasing level of SPC.