• Culinary science and hospitality research
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• v.20 no.3
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• pp.148-160
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• 2014

This study was performed to find out the optimum condition of a thickening agent for brown sauce. Four thickening agents of non-glutinous rice, glutinous rice and potato starch, and roux as control thickeners were tested with various concentrations of each thickener to investigate the quality characteristics of brown sauce samples. The moisture contents of the brown sauce samples thickened with non-glutinous rice, glutinous rice and potato starch showed higher than that of the brown sauce samples thickened with roux. The brown sauce samples thickened with non-glutinous rice and potato starch had higher viscosity than the samples with glutinous rice and roux. The brown sauce with roux showed the highest on Hunter's color L and b value and the brown sauce with non-glutinous rice showed the highest a value. The brown sauce samples with 11% of roux, 11% of non-glutinous rice powder, 12% of glutinous rice powder and 6% of potato starch showed significantly higher scores in the acceptance test. The brown sauce with 6% potato starch resulted in the highest score in brown color, gloss, and transparency, and the brown sauce with 11% of roux showed the highest roast smell. The brown sauces with 6% potato starch and 11% of roux showed higher viscosity than the samples with 11% of non-glutinous rice and 12% of glutinous rice.

• Macromolecular Research
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• v.9 no.6
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• pp.297-302
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• 2001

Rice starch was incorporated into linear low density polyethylene (LLDPE) using a Brabender Plastic-Corder internal mixer at a temperature of 140$\^{C}$ and 40 rpm. The starch loading was varied from 0 to 30% with 5 intervals. Studies on brabender torque development, mechanical properties and water absorption were investigated. The starch loading did not influence the brabender torque significantly. With respect to mechanical properties; the tensile strength and elongation at break decrease with increasing starch loading. The Young's modulus also increases with the starch filling. Mechanical properties were deteriorated as the starch absorbed moisture. The rate of water absorption was dependent on the starch filling in the composites. The scanning electron microscope (SEM) analysis was performed for the tensile fracture surfaces and it revealed the starch agglomeration and a poor dispersion of starch in the LLDPE matrix.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.294-294
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• 2017

Rice (Oryza sativa L.) is one of the main agricultural crops in Asian countries, including Korea, and is considered as the most important staple food in the world. Rice is also processed into flour, which is consumed through various foods such as cake, noodle, bread, and confectionary. Rice flour quality is highly dependent on variety and milling conditions. Producing rice flour with fine particles is more difficult than wheat flour because of its grain hardness. The Korean rice varieties representing different amylose contents were selected for this study. The relationship between the morphological and starch characteristics of rice kernels and the appropriate varieties for producing good-quality, dry-milled rice flour were examined. The hardness of the rice kernels was determined by measuring the pressure at the grain breakage point. The damaged starch content of the rice flour was determined using a Megazyme starch damage assay kit. The particle-size distribution of the rice flour was measured as the volume-base distribution using a laser-diffraction particle size analyzer. The mean particle-size distribution of the dry-milled flour obtained was between $65.3{\sim}105.1{\mu}m$ among the rice varieties. The opaque, non-glutinous, Seolgaeng rice demonstrated a narrow peak at the fine size, whereas the entire particle-distribution range for other varieties was wide. Seolgaeng exhibited significantly lower damaged starch content of dry-milled flour than the other varieties (p < 0.05). Seolgaeng showed lowest in energy consumption on rice flour production with 200 mesh particle size. Accordingly, it is possible to produce dry-milled rice flour which is similar to wheat flour that would considerably reduce milling costs.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.766-771
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• 1989

physicochemical properties of rice starch isolated from eight varieties were examined to evaluate the rice processing suitability The amylose contents of rice starch were varied with 16.7-29.7%, and IR 30, Godael, Aguja and Lengkwang varieties showed higher amylose content than the other varieties. The water binding capacity and blue value were in the range of 87.0 103.0 and 0.178-0.305, respectively. As the amylose content increased, the amylogram pasting temperature and the break down ratio increased, while the peak viscosity did not show any significant difference. The transmittance of 0.1% starch suspension slowly increased at $50^{\circ}C$ in the low-amylose content rice group, and rapidly increased at $65^{\circ}C$ in the high-amylose content rice group, but there were no differences above $75^{\circ}C$ among varieties. Also the low-amylose rice starch showed higher values in the swelling power and solubility. The hardness of the 30% rice starch gels was low in low-amylose one. During storage at $20^{\circ}C$ for 14 days, the increment of hardness was more slow in high-amylose one. The retrogradation velocity constant of rice starch gel by Avrami equation was the highest as 0.219 in Aguja variety.

• Journal of Microbiology and Biotechnology
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• v.19 no.10
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• pp.1161-1168
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• 2009

Ethanol production by the simultaneous saccharification and fermentation (SSF) of low-value rice wine cake (RWC) without cooking was investigated. RWC is the filtered solid waste of fermented rice wine mash and contains 53% raw starch. For the SSF, the RWC slurry was mixed with the raw-starch-digesting enzyme of Rhizopus sp. and yeast, where the yeast strain was selected from 300 strains and identified as Saccharomyces cerevisiae KV25. The highest efficiency (94%) of ethanol production was achieved when the uncooked RWC slurry contained 23.03% starch. The optimal SSF conditions were determined as 1.125 units of the raw-starch-digesting enzyme per gram of RWC, a fermentation temperature of $30^{\circ}C$, slurry pH of 4.5, 36-h-old seeding culture, initial yeast cell number of $2{\times}10^7$ per ml of slurry, 17 mM of urea as the nitrogen additive, 0.25 mM of $Cu^{2+}$ as the metal ion additive, and a fermentation time of 90 h. Under these optimal conditions, the ethanol production resulting from the SSF of the uncooked RWC slurry was improved to 16.8% (v/v) from 15.1% (v/v) of pre-optimization.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.2
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• pp.219-222
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• 2005

Some structural characteristics of hot-water soluble and insoluble starches (waxy black rice starch) were investigated. The hot-water soluble material content of waxy black rice starch was higher (16.6%) than that (13.4%) of Shinsunchalbyeo starch heated at 98$^{\circ}C$ for 8 min. The Amax and absorbance at 625 nm for hot-water soluble and insoluble material of waxy black rice starch were lower than those of Shinsunchalbyeo. Elution patterns of hot water soluble and insoluble materials by gel permeation chromatography (Sepharose CL-2B) were similar in both samples.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.4
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• pp.428-435
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• 1992

Intrinsic viscosity and gelatinization properties of brown rice starches of Japonica and Tonsil type cultivars were investigated. The intrinsic viscosity was similar between the two cultivars. The gelatinization temperature of Japonica brown rice starch determined by differential scanning calorimetry was higher than that of Tonsil brown rice starch. However, the range of gelatinization temperature, gelatinization enthalpy and the water content for gelatinization were similar between the two starches. The treatment of starch at 6$0^{\circ}C$ for 24hr increased the gelatinization temperature and gelatinization enthalpy and decreased the range of geltinization temperature. The water content for gelatinization was negatively correlated with the range of gelatinization temperature in case of Japonica starch and with the intrinsic viscosity in case of Tonsil one. The in-trinsic viscosities of both Japonica and Tonsil starches were positively correlated with gelatinization enthalpy.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.814-818
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• 2008

Com and rice starches were physically modified by planetary mill. While native starches showed high peak viscosities (1,001 and 563 cp), it decreased largely (42 and 20 cp for rice and com starch, respectively) after 2 hr of physical modification. When two starches were co-ground, peak viscosities decreased more largely than single ground one only in 30 min, indicating the pasting properties could be easily changed by co-grinding. Especially, the higher the amount of com starch, the viscosity decreased more largely, which means that paste stability could be controlled also by changing the ratio of com and rice starch. Mean particle size increased with physical modification time since particles became spread because of shear force. There were also changes in surface morphology after physical modification. Fluid property, such as mean time to avalanche (MTA), was improved (from $6.16{\pm}0.47$ and $8.37{\pm}1.23\;sec$ to $5.47{\pm}0.78$ and $5.26{\pm}1.37\;sec$ for rice and com starch, respectively) by physical modification. Pasting property, such as swelling power, was also improved by physical modification. These mean that native starches can be applied to both conventional powder and new paste-food industry more efficiently by physical modification.

• Journal of Food Hygiene and Safety
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• v.6 no.3
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• pp.127-131
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• 1991

${\alpha}-amylase\;and\;{\beta}-amylase$ were extracted from barley and wheat malt, respectively. Their kinetic parameters on gultinous and nonglutinous rice starch were examined. During the germination of barley and wheat, the increaments of ATP levels were significant after 2-day germination and the levels were reduced after 5 days. The dry weights were decreased after 3 days. The activities of amylases were the highest for 6 days in the barley and wheat malt. As for ${\alpha}-amylase$, that the substrate affinity of barley malt on nonglutionous rice starch was greater than other cases. The $V_{max}$ values of ${\alpha}-amylase$ from wheat malt on either type of rice starch showed high, and from barley malt on nonglutinous rice starch were high. The ${\beta}-amylse$ from barley malt showed high substrate affinity on the glutinous rice starch, and $V_{max}$ value of the enzyme from wheat malt on glutinous rice starch was higher than other. The substrate efficiency ($V_{max}/K_{m}$) of ${\beta}-amylase$ on the non glutinous rice strach was better than other cases.

• Microbiology and Biotechnology Letters
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• v.18 no.5
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• pp.506-510
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• 1990

The Takju brewing of raw rice starch was carried out by the simultaneous saccharification- fermentation using Rhizopus sp. koji and yeast, and compared with the Takju mash brewed by the conventional method. Rhitopus koji was prepared with uncooked rice for Takju brewing without cooking of rice starch. Alcohol concentration of Takju mash brewed with uncooked rice was slightly higher of 1.8% than that with cooked one. Amino acid contents was almost double and fuse1 oil contents was lower in uncooked brewing. The Takju mash prepared after fermentation without cooking of rice had a characteristic odor of raw material and a good quality of taste.