• Journal of the East Asian Society of Dietary Life
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• v.7 no.3
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• pp.315-324
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• 1997

Physicochemical properties of potato starches oxidized with sodium hypochlorite containing 1.5, 3.0, 4.5, and 6.0% active Cl/g starch at pH 7.0 were examined. Carboxyl group contents of oxidized potato starches were proportional to active chlorine concentration in use and water binding capacity, alkali number, and solubility increased with increasing the degree of oxidation. Blue value and iodine binding property indicated the change of amylose structure by the oxidation. Gelatinization trends obtained from transmittance and DSC thermograms showed that gelatinization temperature was lower as starch was oxidized higher. X-ray diffraction patterns and scanning electron micrographs implied oxidation might occur on the surface amorphous regions of starch granule.

• Journal of the Korean Society of Food Culture
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• v.25 no.1
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• pp.82-90
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• 2010

In this study, the rheological properties of doughs blended with 5% to 20% fermented rice bran (FRB) were investigated using farinographs, amylographs, extensographs, and SEM. In the farinograph analysis, the water absorption decreased and the replacement ratio of FRB increased over the time of development of the dough. The stability time of the dough was shortened, and the degree of softening decreased with added volume of FRB. The amylograph analysis showed that the temperature at the beginning of gelatinization showed a tendency to increase with increasing replacement ratio of FRB, but the gelatinization temperature showed no significant difference between the FRB-added groups and control group. The extensograph analysis showed that when the replacement ratio of FRB was over 10%, the extension of the dough decreased while the resistance was increased. In the SEM analysis, the added dough with less than 10% FRB had similar characteristics in gluten matrix and gas bubbles to those of the control of wheat flour alone. It was concluded that an added FRB volume of below 10% is most suitable for bread making.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.269-269
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• 2017

Germination is one of the techniques used to enhance the texture properties and nutritional value of the brown rice (BR). Therefore, germinated BR (GBR) has received significant attention during the last decade. Physicochemical and cooking properties of brown rice were examined before and after germination. Germination raised the cooking properties, such as water absorption, expanded volume and soluble solid of cooked BR (brown rice). The texture, measured using tensipresser, was significantly improved by germination. The hardness of cooked BR was decreased by germination, but the GBR was sticker. In RVA, all viscosity value (peak viscosity, break down, set back, and final viscosity) of germinated rice flour was also reduced while gelatinization temperature did not change. Amylose content and amylopectin chain length distribution of BR starch were slightly changed by germination. Overall results revealed that germination was an effective tool to improve texture and cooking properties of BR.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.4
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• pp.519-526
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• 1997

Physicochemical properties of potato starches with degree of substitution of 0-0.2645 hydroxypropylated with propylene oxide were examined. Hydorxypropyl group content of the starch was proportional to propylene oxide concentration. Water binding capacity increased but pH decreased with the increase of degree of substitution. Blue value and iodine absorption property decreased with the increase of hydroxypropylation. Differential scanning calorimeter showed that hydroxypropylation lowered the gelatinization temperature of the starch. Relative crystallinity in X-ray diffraction patterns decreased and starch granule observed by scanning electron microscopy was destroyed by hydroxypropylation. This result implied that high level hydroxypropylation affected the crystal region as well as amorphous region of starch.

• The Korean Journal of Food And Nutrition
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• v.12 no.5
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• pp.523-528
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• 1999

The influence of ginseng on the paste or gelatinization properties by amylograph and mixing properties by farinograph of wheat flour and on quality properties color cooking quality textural and sensory properties and reducing microbial population of LL(Long Life) noodles was studied. The contents of ginseng used were from 5% to 10% based on flour weight. The viscosity property of wheat flour with ginseng was increased the initial pasting temperature but the amylograph peak viscosity were decreased in vice versa. The farinograph absorption stability and breakdown were increased by ginseng. The whiteness of Ll nodles manufactured with ginseng was lower than that of control The shear extrusion force and hardness of LL noodles manufactured with ginseng were shown much higher value than those of control. At cooking quality examination of LL noodles manufactured with ginseng weight of cooked LL noodles was decreased but volum was appeared in ice versa,. Extraction amounts of LL noodles manufactured with ginseng during cooking were much smaller than those of control Total count of microorganism of Ll noodles manufactured with ginseng were decreased during storage at 3$0^{\circ}C$ Sensory properties of cooked LL noodles which was manufactured with ginseng showed quite acceptable. Based on the cooking and sensory evaluation test addition of 7.0% ginseng to wheat flour may be suitable for processing LL noodles.

• The Korean Journal of Food And Nutrition
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• v.12 no.3
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• pp.252-257
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• 1999

In an attempt to evaluate the effects of calcium on paste or gelatinization properties by amylograph and mixing properties by farinograph of wheat flour and on viscosity property cooking quality textural and sensory properties of Ramyon were examined. The contents of calcium used were from 1.0% to 3.0% based on flour weight. The viscosity property of wheat flour with calcium was increased the initial past-ing temperature but the amylograph peak viscosity were decreased in vice versa. The farinograph absorp-tion stability and breakdown were increased by calcium. The shear extrusion force and hardness of Ram-yon manufactured with calcium were shown much higher value than those of control. At cooking quality examination of Ramyon manufactured with calcium weight of cooked Ramyon was increased by volume was decreased. Extraction amounts of Ramyon manufactured with calcium during cooking were much smaller than those of control. These changes will provided many advantages in the preparation of Ram-yon. The I2 reaction value of Ramyon manufactured with calcium and control were shown to almost same values. Sensory properties of cooked Ramyon which was manufactured with calcium showed quite acceptable. Based on the cooking and sensory evaluation test addition of 0.3% calcim to wheat flour may be suitable for processing Ramyon.

• Food Engineering Progress
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• v.15 no.2
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• pp.169-174
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• 2011

This study was performed to analyze the effects of ultra fine pulverization (UFP) on the physicochemical properties of sweet potato starch (SPS). The average diameter and specific surface area of the SPS was decreased from 22.94 to 10.25 $\mu$m and from 0.879 to 1.909 $m^2$ /g throughout UFP, respectively, and the damaged starch content was increased from 13.7 to 99.2%. The pulverized sweet potato starch (PSPS) had higher swelling power, solubility, and transmittance values than the SPS. X-ray diffractograms revealed that the SPS had a C-type pattern, which disappeared in PSPS. The rapid visco analysis (RVA) characteristics, peak viscosity, break down, and set back of SPS ceased to exist in PSPS. According to differential scanning calorimetry (DSC) curves, the peak temperature ($T_p$) and gelatinization enthalpy ($\Delta$E) of SPS were $71.95^{\circ}C$ and 10.40 J/g, respectively, while these remained undetected in PSPS. The enzymatic digestibilities of SPS and PSPS were 61.7 and 84.7%, respectively.

• The Korean Journal of Food And Nutrition
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• v.32 no.4
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• pp.304-311
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• 2019

Ohmic heating is a heating method based on the principle when an electrical current passes through food. Since this method is internal, electrical current damage occurred during heating treatment. The results of ohmic heated starch's external structure, X-ray diffraction, DSC analysis and RVA were differed from those of conventional heating at the same temperature. Several starches changed more rigid by structure re-aggregation. This change in starch was caused by change of physical, chemical, rheological property. The rheology of ohmic heated potato and corn starch of different heated methods were compared with chemically modified starch. After gelatinization, sample starch suspension (2%, 3%) measured flow curves by rheometer. Cross-linked chemically modified starch's shear stress was decreased with degree of substitution reversibly. Ohmic heated more dramatic, at $60^{\circ}C$. Potato starch's shear stress was less than commercial high cross-linked modified starch. Flow curves of potato starches measured at $4^{\circ}C$, $10^{\circ}C$, $20^{\circ}C$. Showed that Ohmic heated potato starch's shear stress ranging between $4^{\circ}C$ and $20^{\circ}C$ was narrower than modified starch. According to this study, ohmic heated potato starch can be used by decreasing viscosity agent like cross-linked modified starch.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.470-475
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• 1988

The extrusion-cooking method was used to make gelatinized rice extrudate from rice grits of the Chuchung and the Samgang varieties. The water contents of raw rice grits varied from 15% to 25%, and the physicochemical properties of extrudates were evaluated. Low moisture content showed high expansion ratio in rice extrudate and resulted in some decrease in gelatinization, bulk density and break strength. Increasing the water content to 25% resulted in increase in water absoption index but decrease in water solubility index. With regards to Brabender Amylograph values and rheological patterns, higher moisture content in raw materials revealed stronger pseudoplastic flow behavior with lower viscogram property. Hunter's color values of rice flours extruded at low water content were low in b values. Scanning electron microscopy demonstrated the break-down of starch granules during extrusion.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.700-706
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• 2005

The objectives of this research were to analyze physicochemical properties of physically modified rice starch which was prepared by hydro-shear homogenizer and ultrasonic homogenizer. The 5:1 of water to starch ratio, 20,500 rpm of hydro-shear homogenizer, and 5 sec of pulse and 40 kHz of frequency of ultrasonic homogenizer, which were operated for 10 min. The 1/3 of size reduction of raw rice starch and gelatinized rice starch, and reduced of particle size were achieved by above processing conditions. The homogenization of raw rice starch and gelatinized rice starch were higher values of specific area, transmittance, solubility and swelling power than control. While, these had lower value of apparent viscosity than control. In raw rice starch, the gelatinization characteristics of ultrasonic homogenizer treated rice starch had some higher values of gelatinization temperature, peak temperature and enthalpy than those of control. While, those of hydro-shear homogenizer treated rice starch had similar values to those of control.