• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.38-43
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• 2003

The rheological properties of wheat flour and black rice flour dough were investigated in dough added with 0, 10, 20, and 30% of black rice flour (BRF). Increase in BRF concentration resulted in: decreases in protein and gluten contents, whereas ash content increased; decreases in water absorption, stability, development time, elasticity, and valorimeter value of the dough, whereas increase in weakness of the dough, as revealed through farinogram; low initial pasting temperature and temperature at peak viscosity, and decreases in viscosity at peak point and at $94^{\circ}C$, as revealed through amylogram; decreases in extensibility, resistance to extension, and energy, whereas increase in R/E ratio, as revealed through extensogram.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1052-1058
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• 1996

The effect of varietal differences of rice starches by amylose content and gel consistency on the retrogradation behavior was studied. Setback viscosity of rice flour measured in a Brabender amylograph was significantly affected by amylose content as well as gel consistency. Increase in the rigidity modulus (E) of rice starch gels during storage determined by using texture analyzer indicated that amylose content was an important factor in terms of hardness increase. Kinetics of retrogradation showed that time constant of rice starch gels was influenced by amylose content, but not by gel consistency.

• Korean Journal of Food Science and Technology
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• v.22 no.1
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• pp.38-43
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• 1990

Effects of concentration (5-8%, db) and heating temperature $(80^{\circ}C-95^{\circ}C)$ on rheological of mungbean starch were examined. The pasting curve by amylograph revealed no peak viscosity and the viscosity continued to increase during cooking, regardless the starch concentrations. Mungbean starch paste showed a pseudoplastic flow behavior with yield stress. The consistency index of paste increased as the heating temperature was raised at a given concentration. However, flow behavior index showed opposite trend. The percent sag of starch gel stored at $4^{\circ}C$ decreased with the increase of concentration and heating temperature. The firmness of fresh gel prepared from 7 and 8% starch suspensions by heating at $95^{\circ}C$ for 15 min with amylograph was about 2-times higher than that of 6% gel. However, the time constant, reciprocal of rate constant, of starch gels during aging at $4^{\circ}C$ was not significantly influenced by concentrations and heating temperatures.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.3
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• pp.414-419
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• 2005

Newly harvested milled rice and stored milled rice for 2 years were steeped at the elevated temperatures of 40, 50, and 60℃ for 2hr, and physicochemical properties of the wet-milled rice flour were investigated. The lightness of rice flour was slightly higher in the newly harvested milled-rice, while yellowness was higher in the stored milled rice. For both newly harvested and stored milled rice, WAI, WSI, and gel consistency increased as steeping temperature increased. The amylograph pasting properties indicated that increasing steeping temperature increased peak viscosity. The differential scanning calorimetry (DSC) results of the rice flour showed that increasing steeping temperature increased onset and peak temperatures, with reduced gelatinization enthalphy, suggesting partial annealing occured. Particle size of rice flour from newly harvested milled rice was larger than that from stored milled rice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.3
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• pp.346-351
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• 2009

This study was carried out to determine the rheological properties of bread doughs containing flour-ferments prepared with seed mash obtained by Koji incubation, yeast, and lactic acid bacteria, using farinograph, extensograph, amylograph, and large scale-dough mixer. According to farinograph, the addition of the flour-ferments did not influence the water-absorption rate of doughs, regardless of the kinds of flour-ferments, however, it increased development time and decreased stability of doughs. According to extensograph, both dough resistance and resistance-to-extensibility ratio increased with the addition of flour-ferments. Especially the dough containing the flour-ferments prepared with seed mash, S. cerervisiae, and L. brevis showed the highest resistance-to-extensibility ratio. According to amylograph, although the doughs containing the flour-ferments did not show the differences in gelatinization temperature and temperature at maximum viscosity with the control which does not contain the flour-ferments, they showed lower maximum viscosity than the control. They also showed lower development value and faster development time.

• Culinary science and hospitality research
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• v.15 no.1
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• pp.202-208
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• 2009

This study was conducted to investigate the differences on physicochemical properties and cookie potentialities of Korean wheat cultivars. The protein contents of the wheat cultivars ranged from 8.80$\pm$0.76% to 11.19$\pm$0.25%. Korean wheat cultivars had sedimentation values of 19.82 mL to 35.54 mL. Their peak viscosity range measured by Amylograph was from 60 BU to 640 BU. Diameter of cookies for soft wheat was 8.28 cm and Korean wheat cultivars ranged from 7.63 cm to 8.55 cm. Olgeunmil resulted in a higher cookie diameter and top grain score than the soft wheat. Protein content had significantly negative correlations with the coefficient of cookie diameter(r=-0.838$^*$) and with the top grain score(r=-0.751$^*$). There was a significant correlation between protein content and sedimentation value(r=0.762$^*$).

• Korean Journal of Food Science and Technology
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• v.19 no.1
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• pp.69-74
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• 1987

These studies were conducted to investigate the changes in carbohydrate properties of the endosperm during the stages of maturity. Original moisture continued to decrease while 1,000-kernel weight and test weight increased steadily in all varieties with maturation. Starch content of the endosperm increased continuously by 35 to 40 days after heading. The B-type starch granules synthesis of the the early mature variety, Chokwang, was depressed at the later stages of development. Amylose and amylopectin components of starch both increased as the kernel matured, and amylose-amylopectin ratio also increased during the same period. Amount of pentosan per kernel basis increased throughout the maturation period. Amylograph break-down had a highly negative coefficient correlation with starch and pentosan content of endosperm. Results indicated that wheat maturation was characterized by an increase in the starch and pentosan content of the kernel.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1373-1380
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• 1998

Wet noodles were prepared with wheat flour and mushroom powder (oyster and oak mushrooms), and effects of added mushroom powders on dough rheology and wet noodle quality were examined. Particle size distribution of mushroom powder ranged from 0.04 to $500\;{\mu}m$, which was different from that of wheat flour. The initial pasting temperature in amylograph, and the water absorption and the dough development time in farinograph increased with the increase of mushroom powder. The peak and final viscosities in amylograph, and dough stability in farinograph decreased with the increase of mushroom powder. Decrease of L value and increase of a and b values were shown with the increase of mushroom powder in wheat flour-mushroom powder composite as well as wet noodles. The cooked weight and volume of cooked noodles were decreased, but the turbidity of soup were increased with the addition of mushroom powder. Most of texture parameters (hardness, cohesiveness, chewiness and cutting force) of cooked noodles decreased with the addition of oyster mushroom powder, but increased with the addition of oak mushroom powder. From the result of sensory evaluation, wet noodles containing 3% oyster mushroom powder and 5% oak mushroom powder were rated as high quality wet noodles.

• Korean Journal of Food Science and Technology
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• v.19 no.4
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• pp.382-386
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• 1987

Changes of proteins of whole soybean and soy flour stored under different conditions of humidity (RH 65% and 85%) and packing material (HDPE and OPP/Al/PE film) for 90 days and their influence on formation of soybean curd were investigated. The water holding capacity, total nitrogen, soluble nitrogen, pH and Amylograph viscosity of whole soybean and soy flour were rapidly decreased during storage at high relative humidity. Furthermore, such quality changes were accompanied by considerable differences in final quality of soybean curds; lower volumes of soybean curds. Under the conditions of HDPE and OPP/Al/PE film packing, smaller changes were observed in protein qualify than those without packing.

• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.317-324
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• 1991

Gelatinization behaviours and gel properties of hydroxypropylated corn starches (HPCS) were investigated with differential scanning calorimeter, amylograph and rheometer. Gelatinization temperature of HPCS decreased as degree of substitution increased. The retrogradation of corn starch was greatly reduced by hydroxypropylation, indicating that the association of starch molecules was sterically hindered by hydroxypropyl groups. In HPCS, gel was formed slowly and gel strength decreased resulting in soft and sticky texture. Texture profiles of HPCS gels were similar to those of tapioca and waxy corn starch. HPCS has shown a remarkable increase of paste transparency compared to native corn starch.