• Applied Biological Chemistry
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• v.33 no.1
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• pp.24-33
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• 1990

The changes in water uptake rate, cooking properties, color of rice grains and gelatinization properties of brown and milled rices during storage were studied. The brown and milled rices were stored at $4^{\circ}$ and $25^{\circ}C$ for 5 and 3 months, respectively. The water uptake rate constants of rices during hydration at $30^{\circ}$ were linearly decreased during storage. The volume increase rate also showed similar trend to the water uptake rate. The terminal point of cooking of milled rice at $100^{\circ}$ in a sealed brass vessel was about a half of that of brown rice. The cooking rate of milled rice was 1.8 times faster than that of brown rice. The cooking rate constant of both brown and milled rices linearly decreased with the increase of storage time. The L(lightness) value increased for brown rice grain and remained unchanged for milled rice grain during storage. The peak viscosity of rice flours by amylograph increased during storage, but enthalpy for gelatinization decreased, as measured by differential scanning calorimetry.

• Applied Biological Chemistry
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• v.33 no.1
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• pp.1-7
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• 1990

Starch samples of rice and glutinous rice starches were adjusted to 27 % of moisture and heated at $100^{\circ}C$ for 16 hours, respectively. After the treatment, their physicochemical properties were investigated. The granule shapes of all the starches were polygonal and they became slightly bigger in their sizes after the treatment. All their X-ray diffraction patterns were A types. The specific gravity of the starches decreased to 1.03-1.09 by the treatment. The water binding capacity of rice starches increased, while that of glutinous counterparts slightly decreased. Almost no change in the amount of amylose included was found. Swelling power and solubility were increased with the increase of temperature. At a certain temperature, however, the solubility of the treated starches increased when the swelling power decreased. The initial gelatinization temperatures of Akkibare, Yongmun, and Taebaek starches were $60{\sim}65^{\circ}C$ but those of glutinous rice starch and U.S.A. rice starch were $55{\sim}60^{\circ}C$ and $70{\sim}75^{\circ}C$, respectively, as measured by transmittance. The gelatinization temperature of the treated starches was higher than that of the untreated starches.

• Korean journal of food and cookery science
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• v.5 no.2
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• pp.43-50
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• 1989

Physicochemical properties on defatted potato starches, Irish Cobbler and Dejima, were investigated. The average diameter of the Irish Cobbler and Dejima starch were $22.5-29.8\mu\textrm{m}$, and both the starches had birefringence. Irish Cobbler starch was lower than that of Dejima starch in water binding capacity, swelling power and solubility. Relative crystallinity of both the starches was decreased after defatted. The blue value of Irich Cobbvler and Dejima starch was measured 0.37 and 0.35 respectively Transmittnace of 0.1% starch suspensions was higher on defatted starch than on untreated starch. Differential Scanning Calorimetry of untreated potato starch showeed higher gelatinization temperature in Irish Cobbler starch than in Dejiam starch. The gelatinization enthalpy of untreated starch was higher in Irisch Cobbler starch than in Dejima starch, but, after defatted, it was decreased.

• Applied Biological Chemistry
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• v.34 no.4
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• pp.360-365
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• 1991

Rheological properties of Shinsunchalbyeo(Japonica) and $Hangangchalbyeo(J{\times}Indica)$ waxy-rice starches gelatinized with thermal or alkali solutions were investigated with rotational viscometer(Brabender Viscotron). The two starches showed Bingham pseudoplastics behavior in $4{\sim}8%$ thermal or alkali gelatinized starch solutions. The shear stress of Hangangchalbyeo starch solution gelatinized with thermal or alkali showed higher values than that of Shinsunchalbyeo starch and the difference of the two varieties gelatinized with alkali showed higher values than that gelatinized with thermal. Consistency index and yield stress values of Hangangchalbyeo starch showed higher than that of Shinsunchalbyeo starch in the two gelatinized methods and the difference of the two varieties gelatinized with alkali showed higher values. And it was higher that the deffendence of consistency index on starch concentration and initial starch concentration of yield stress in the alkali gelatinized samples than those of in the thermal gelatinized ones.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.1098-1102
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• 2005

Properties of rice flours prepared from milled and broken rice produced by pre-washing and subsequent drying process were investigated. Compared to untreated ordinary milled rice, pre-washing process slightly increased lightness of rice flour, while decreased yellowness. Both WAI and WSI were higher in the flour from pre-washed rice, and gel consistency was the highest in the flour from pre-washed broken rice. Pre-washed rice showed increased amylograph peak viscosity and reduced setback values. On the other hand, pre-washed broken rice showed decreased peak viscosity and increased setback values. Differential scanning calorimetry (DSC) results showed that the pre-washing process reduced gelatinization onset- and peak temperatures, with increased gelatinization enthalpy. Total bacteria and yeast count were lower in the pre­washed rice, suggesting the pre-washing process could partially eliminate microbial contamination of ordinary milled rice.

• Korean Journal of Food Science and Technology
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• v.53 no.5
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• pp.521-526
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• 2021

This study characterized the chemical structure and physical properties of domestic commercial wheat starch and compared them with those of imported commercial wheat starch. Three varieties of domestic commercial wheat starch (DWS) were compared to three types of imported wheat starch (IWS). The morphology of DWS granules was spherical with diameters 17.0-18.3 ㎛; the IWS granules exhibited various diameter sizes (16.6-17.7 ㎛). The amylose content of both DWS and IWS was between 23.2-23.8%. DWS exhibited smaller gelatinization temperature ranges and gelatinization enthalpies compared to IWS. These results suggest that IWS-PW (plain wheat starch) is a mixture of many types of wheat starch. In conclusion, the quality of domestic wheat flour and imported wheat flour was related to gluten content as well as to the starch properties.

• Korean Journal of Food Science and Technology
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• v.8 no.1
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• pp.42-46
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• 1976

In order to compare the quality of starches, isolated from the various barley and naked barley species, the gelatinization-temperature and alkali number were determined for 11 species of barley and 13 species of naked barley. The results are as follows; 1. Gelatinizations start at $51-59^{\circ}C$ and complete at $58-64^{\circ}C$ in range. Average gelatinization temperature of the starches from naked barley showed $3^{\circ}C$ lower than those from barley while small differences were observed between species for both barleys. 2. Alkali number varies between 8.0 to 9.5. No significant changes of alkali number were observed between both barleys (8.8 for naked barley and 8.7 for barley in average).

• Korean journal of food and cookery science
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• v.15 no.3
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• pp.249-257
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• 1999

Jeung-Pyun is a traditional fermented Korean food with rice flour, water, sugar, salt and unrefined rice wine(Takju). In order to investigate how the addition of soybean has an influence on Jeung-Pyun fermentation, changing to adding amount of soybean 0%, 5%, l0%. 15%, 20% based on rice weight, we carried out sensory evaluation and measured the physicochemical properties, instrumental characteristics and degree of gelatinization. The specific volume of Jeung-Pyun was increased as the more soybean was added. The pH of Jeung-Pyun batter was decreased as the fermentation time was longer, but it was increased as more soybean was added. The degree of gelatinization of Jeung-Pyun was decreased as storage day was longer, but it was high as more soybean was added compared to control(0%). In sensory evaluation, Jeung-Pyun added 5∼10% of soybean was good generally. Correlation coefficient between hardness and degree of gelatinization was high. In instrumental characteristics, hardness was increased only in control for room temperature storage(20$^{\circ}C$), but at 4$^{\circ}C$ it was less increased than control(0%) as more soybean was added. Cohesiveness was decreased generally as storage day was longer at 4$^{\circ}C$, but it was less decreased as more soybean was added. In brittleness at 4$^{\circ}C$, Jeung-Pyun of adding soybean was higher compared to control. In surface structure of Jeung-Pyun observerd by SEM. air pore size was small and distributed regularly as more soybean added. In conclusion. it can be suggested that the addition of soybean improve the quality of Jeung-Pyun.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.15-22
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• 2005

Extrusion with enzyme treatment improved processing characteristics and physiological activity of whole grains, strongly suggesting industrial potential of whole grains for production of cereal-based functional foods containing activated nutraceuticals. Physicochemical properties of whole grains prepared by extrusion were characterized in terms of vitamin, mineral, and resistant starch contents, gelatinization, and digestibility in comparison with those of raw and roasted grains. Extrusion increased grain gelatinization, with degree of gelatinization in extruded barley being seven times higher than that of raw barley. Extrusion improved digestibility of whole grains in comparison with those of raw and roasted grains. Dispersibility of starch was improved through extrusion, while content of resistant starch decreased. Release of ${\beta}-sitosterol$ present in whole grains increased 13-fold when both extrusion and enzyme treatment were used.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.994-998
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• 1999

To evaluate the effects of sucrose-fatty acid ester (SE) on bread-making characteristics, the dough mixing, gelatinization, baking properties with the addition of SE alone and together with other surfactants were investigated. SE increased the peak time and the peak height in mixogram, indicating that it contributed the elasticity of dough. In farinogram, SE increased the peak time and mechanical tolerance index, but reduced the dough stability. SE increased the peak viscosity and reduced the gelatinization temperature and maximum consistency temperature in amylogram. SE increased the specific volume of bread loaf and retarded the increase in hardness of bread during storage, showing its anti-staling effects. The maximum anti-staling effect of SE was observed at 0.5% level. The addition of SE (0.2%), SSL (0.15%) and ES-95 (0.15%) blend showed the maximum specific loaf volume, and that of SE (0.25%) and SSL (0.25%) did the maximum anti-staling effect.