• Korean journal of food and cookery science
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• v.12 no.4
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• pp.557-561
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• 1996

Physicochemical properties of nonwaxy (Dongjin byeo) and waxy (Sin-seunchal byeo) brown rice flour were investigated. The proximate composition of nonwaxy brown rice flour was 7.02% of protein, 1.14％ of ash, 3.2% of lipid and that of wfny brown rice was 7.74% of protein, 1.48% of ash,4.83% of lipid. X-ray dif- fraction patterns were A types, and relatives crystallinity of nonwaxy brown rice flour was higher than that of waxy brown rice flour. Swelling power and solubility increased with the increase of temperature, waxy brown rice flour showed higher than nonwaxy rice flour until 70$^{\circ}C$, but lower after 80$^{\circ}C$. The gelatinization temperature, breakdown and consistency of nonwaxy brown rice flour by amylogram were higher than those of the waxy brown rice flour but setback was same. The initial gelatinization temperature and the enthalpy of nonwaxy brown rice flour by DSC were higher than those of the waxy brown rice flour.

• Journal of the East Asian Society of Dietary Life
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• v.12 no.6
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• pp.574-579
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• 2002

The effect of Woomegi Dduct mixed with Tack-ioo and So-ju, and made of glutinous rice flour added with various proportions of nonwaxy rice and wheat flour, were studied by the textural and the sensory characteristics. Springiness, gumminess of Woomegi Dduck added with wheat flour tended to be higher than the one with nonwaxy rice flour and cohesiveness tended to increase as the addition amount of glutinous rice flour increased. The degree of gelatinization tended to decrease as the addition of nonwaxy rice flour and wheat flour contents increased from 10 to 50% Overall sensory score of the sample with 50% of wheat flour added to the glutinous rice flour and mixed with Tack-joo was the highest.

• Korean journal of food and cookery science
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• v.17 no.4
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• pp.309-315
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• 2001

The effects of soaking time of nonwaxy rice and particle size of rice flour on the properties of nonwaxy rice flour after steeping at room temperature were investigated. Nonwaxy rice was soaked at 20$^{\circ}C$ for 0, 1, 12, or 24hr, dried at room temperature and milled. Nonwaxy rice flours were passed through 45 mesh or 100 mesh sieve, and were compared for the properties depending on the particle size and soaking time. The particles of rice flour were separated into 10$\mu\textrm{m}$∼30$\mu\textrm{m}$ and 40$\mu\textrm{m}$∼80$\mu\textrm{m}$ groups, and the amount of large particle size(40$\mu\textrm{m}$∼80$\mu\textrm{m}$) was greater in the flour sieved through 45 mesh than 100 mesh sieve. The protein and ash contents decreased and amylose contents increased as the soaking time increased. The water-binding capacity increased rapidly up to 1 hr of soaking and increased slowly thereafter. The swelling power and the solubility increased with temperature rising in the range of 65$^{\circ}C$∼95$^{\circ}C$, and these two properties increased rapidly up to 12 hr of soaking. Peak viscosity and breakdown of the pastes prepared with 12 hr-soaked nonwaxy rice flour were higher than those with 1 hr-soaked ones, while the setback and viscosity at 95$^{\circ}C$ of 12 hr-soaked ones were lower than 1hr-soaked ones.

• Korean journal of food and cookery science
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• v.13 no.4
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• pp.478-483
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• 1997

The effects of defatting by ether or 85% methanol on the properties of nonwaxy rice flours (Odaebyeo and Mankeumbyeo) were investigated. Starch granules in the rice flour were all polygonal and showed all A-type crystalline patterns regardless of defatting. Amylose content of the rice flour extracted by ether (crude lipid-defatted rice flour, CLDRF) was similar to the untreated (untreated rice flour, URF), however, that of 85% methanol (total lipid-defatted rice flour, TLDRF) was increased. Defatting decreased the water binding capacities of rice flour in all samples. The swelling power of rice flour was higher in Odaebyeo than Mankeumbyeo, and that of CLDRF showed a similar pattern to the untreated. Swelling power was the highest in TLDRF up to 85$^{\circ}C$, but decreased in the following order CLDRF > URF > TLDRF at above 95$^{\circ}C$. A similar pattern was observed in the leached soluble fraction, and its apparent amyloae content was increased rapidly at above 85$^{\circ}C$.

• Food Science and Preservation
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• v.6 no.1
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• pp.81-86
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• 1999

The textural characteristics of nonxaxy rice flour gels and rice cake(Injolmi) with different water contents and additives were evaluated after freezing and microwave heating. As moisture content of rice flour gels increased from 45% to 55%, its hardness and gumminess decreased, but adhesive and cohesiveness had no significant difference. Microwave heating did not markedly affect the texture but frozen storage was very effective to prevent the hardening of products. Hardness of reheated rice gels increased more rapidly in non-packaged sample than in PE wrap film and affected by storage time of 24hrs at 20$^{\circ}C$. As sugar content of rice flour gels increased from 0% to 10%, its hardness, adhesiveness, and gumminess decreased, while cohesiveness did not change.

• Korean Journal of Human Ecology
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• v.14 no.6
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• pp.1037-1046
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• 2005

Using three consecutive years' harvested rices and their starches isolated from rice flours by alkaline method, it was found that no significant aging effect on rice flour and starch was observed based on following results. Proximate data of flours or starches showed in similarity, except high level of crude fat in rice flour and rice starch harvested in 2002. In SEM, the surface of aged rice flour had slightly layered shape due to possible abrasion during storage, and that of aged starch showed more smooth and less rigid polygonal shape. X-ray diffraction patterns of flours and starches were all A type, and crystallinity of rice starch harvested in 2000 had the smallest. From tristimulus colorimetry (Hunterlab Color), total color difference ($\Delta$E) calculated from L, a, and b gave less color difference with the darkest in 2002 harvested one among flours and the lightest in 2001 one among starches. WBCs of both 2002 rice flour and starch were the lowest among samples studied. At 80$^{\circ}C$, swelling power and solubility of rice starches harvested in 2000, 2001 and 2002 were 14.35, 9.75; 14.04, 9.6; and 12.49, 8.82, respectively. The highest peak viscosities measured by RVA were shown both in 2001 rice flour and in its starch. Starch and milled rice flour harvested in 2000 had higher hydrolytic $\alpha$-amylase, compared to other flour and starch samples.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.879-884
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• 2004

Effects of soaking time and particle size on physicochemical properties of nonwaxy rice flour were investigated. Nonwaxy rice grains were soaked at $4^{\circ}C$ for 0, 1, 12, and 24 hr, dried at room temperature, and milled. Resulting flours were passed through 45-mesh ($<355\;{\mu}m$, IL45) and 100-mesh ($<150\;{\mu}m$, IL100) sieves and separated into $<40\;{\mu}m\;and\;40-100\;{\mu}m$ series. IL45 series showed higher amount of large particles ($40-100\;{\mu}m$) than IL100 series. As the soaking time increased, protein and ash contents decreased, and amylose content, water-binding capacity, swelling power, and solubity of nonwaxy rice flours increased. Swelling power and solubility of nonwaxy rice flours also increased between $65-85^{\circ}C$. Water-binding capacity, swelling power, and solubility of IL100 series were higher than those of IL45 series. 12 hr-soaked nonwaxy rice flour pastes showed higher peak viscosity and breakdown but lower setback and viscosity at 95 and $50^{\circ}C$ than 1 hr-soaked ones. X-Ray diffractograms of nonwaxy rice flours were not affected, whereas surface appearance was affected, by soaking time and particle size.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.268-275
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• 2004

Effects of soaking time and particle size on physicochemical properties of nonwaxy rice flour were investigated. Nonwaxy rice grains were soaked at $4^{\circ}C$ for 0, 1, 12, and 24 hr, dried at room temperature, and milled, Resulting flours were passed through 45-mesh ($<355{\mu}m,\;IL45$) and 100-mesh ($<150{\mu}m\;IL100$) sieves and separated into $<40{\mu}m\;and\;40-100{\mu}m$ series. IL45 series showed higher amount of large particles ($40-100{\mu}m$) than IL100 series. As the soaking time increased, protein and ash contents decreased, and amylose content, water-binding capacity, swelling power, and solubity of nonwaxy rice flours increased. Swelling power and solibility of nonwaxy rice flours also increased between $65-85^{\circ}C$. Water-binding capacity, swelling power, and solubility of IL100 series were higher than those of IL45 series. 12 hr-soaked nonwaxy rice flour pastes showed higher peak viscosity and breakdown but lower setback and visicosity at $95\;and\;50^{\circ}C$ than 1 hr-soaked ones. X-Ray diffractograms of nonwaxy rice flours were not affected, whereas surface appearance was affected, by soaking time and particle size.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.959-964
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• 1996

The physicochemical and gelatinization properties of rice flours, which were prepared by polishing nonwaxy brown rice (Dongjin byeo), depending on polishing degrees were investigated. The contents of protein, ash, lipid and fiber decreased significantly as the degrees of polishing increased and water uptake of rice grains decreased during hydration. When the surface of the soaked rice grains was examined by the SEM, extensive crack formation was observed. The water binding capacities, swelling power and solubility of rice flour increased as the polishing degree increased. By the amylogram, the initial gelatinization temperatures of rice flour decreased as the polishing degree increased and the peak viscosities, the breakdown and consistency of rice flour increased as the polishing degree increased.

• Applied Biological Chemistry
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• v.39 no.1
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• pp.44-48
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• 1996

Effects of storage temperature on the retrogradation of 50% nonwaxy rice flour gels stored at $20^{\circ}C,\;4^{\circ}C\;and\;-18^{\circ}C$ for 6 days were investigated by ${\alpha}-amylase-iodine$ method, differential scanning calorimetry(DSC) and x-ray diffractometry. The retrogradation of gels increased with increasing storage time and the initial retrogradation rate was higher. The degree of retrogradation gels stored at different temperature increased as following order, $-18^{\circ}C>20^{\circ}C>4^{\circ}C$. The enthalpy of retrograded rice flour by DSC showed similar as the degree of retrogradation by ${\alpha}-amylase-iodine$ method, but the differences between storage temperatures were clear in using ${\alpha}-amylase-iodine$ method. X-ray diffraction patterns of gels stored at $4^{\circ}C\;and\;20^{\circ}C$ showed small peaks at $2{\theta}=17^{\circ}\;and\;20^{\circ}$, but the difference was not detected.