• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.57-61
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• 1991

Rheological properties of Tongjinbyeo(Japonica) and Samgangbyeo($J{\times}Indica$) 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. Rheological properties of thermal gelatinized starch solutions were similar between the two varieties. However, alkali gelatinized Samgangbyeo starch solutions showed higher values of yield stress and consistency index than that of Tongjinbyeo starch. The values of pseudoplasticity, yield stress and consistency index were higher in the thermal gelatinized samples than those of in the alkali gelatinized ones.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.826-831
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• 1989

The rheological properties of concentrated Kochujang (Korean red pepper paste)-water suspensions were investigated. The rheological behavior of Kochujang-water suspension was illustrated by Herschel-Bulkley equation. All Kochujang-water suspensions with 12.5-100% of water addition showed pseudoplasticity in yield stress at the shear rate range of $0.25-179.20sec^{-1}$., but at the shear rate above $5.16 sec^{-1}$, more shear thinning behavior was observed with increasing shear rate. Also, pseudoplasticity of the suspension became weak by increasing water addition and decreasing temperature, The temperature dependence of consistency index on Kochujang-suspension was very low and the values of consistency index was lowered by increasing solid contents, but as heating, the values of that was increased. It was suggested that the main components responsible for rheological behavior of the suspensions at high temperature might be undigested starch or protein in Kochujang. Also, the changes of rheological behavior with vinegar addtion was only due to dilution effect.

• Food Industry
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• s.132
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• pp.9-18
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• 1995

• Bulletin of Food Technology
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• v.15 no.1
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• pp.27-33
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• 2002

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.131-135
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• 1985

The rheological studies on dilute and concentrate solutions of naked and covered barley starches were carried out with various viscosimeters. The rheology of dilute solutions (0.05-0.3%) were characterized by intrinsic viscosity and related parameter according to Huggins equation. Also, the rheology of the solutions of higher concentrations (1-5%) were characterized by time dependent characteristics and pseudoplastic behaviors. The values of consistency index according to the power equation were exponen tially dependent upon concentration and temperature. The results showed that the rheological properties could differ greatly due to difference in varieties. The naked barley starch exhibited higher intrinsic viscosity, more thixotropic behavior and more dependence of consistency index on concentration and temperature than the covered barley starch.

• Korean Journal of Food Science and Technology
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• v.24 no.1
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• pp.54-58
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• 1992

The reological properties of commercial corn starch solutions at various concentrations($4{\sim}9%$) and temperatures($30{\sim}60^{\circ}C$) were investigated. The rheological behavior of corn starch solutions was illustrated by Herschel-Bulkley equation and exhibited pseudoplastic behavior with yield stress. The degree of pseudoplasticity of starch solution increased as the starch concentration increased but was independent on temperature. Apparent viscosity and yield stress of starch solutions were exponentially dependent on concentration and temperature. The critical concentrations for sol-gel transition and for the onset of close-packing of the starch granules were $6.22{\sim}6.52%\;and\;2.68{\sim}2.78%$ respectively.

• Bulletin of Food Technology
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• v.13 no.3
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• pp.54-63
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• 2000

• Applied Biological Chemistry
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• v.41 no.5
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• pp.367-371
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• 1998

The characteristics of four samples of noodle flours milled from Australian Standard White(ASW) wheat were compared with one sample of noodle flour prepared from a blend of hard red winter(HRW) and western white(WW) American wheats. The ASW flours had lower content of protein and ash. Farinograms revealed that the absorption of the ASW flours was slightly higher than that of the HRW-WW flour. The mixing time, however, showed no difference between ASW flours and HRW-WW flour. The stability and the mechanical tolerance index were different among ASW flours, which were lower than HRW-WW flour. The ratios of resistance to extention determined by extensigraph for ASW flours were higher except one flour than HRW-WW flour. The flours showed characteristic mean particle sizes, which may reflect the differences in hardness of wheat used in the flour production. Farinograph indices showed no correlations with protein content and extensigraph indices. The amylograph peak viscosity was inversely correlated with the protein content (p<0.05).

• Korean Journal of Food Science and Technology
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• v.24 no.2
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• pp.127-131
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• 1992

The effects of chlorine treatment on the rheological properties (farinogram, extensogram, amylogram) of soft white wheat flour were studied by treating flour with different amounts (1, 2 and 4 ounces per 100 pounds of flour) of liquidized chlorine gas. Departure time, water absorption and dough stability increased while mechanical tolerance index decreased as the level of chlorine increased. It was appeared that extensibility and resistance at chlorine level of 1 to 2 oz was appropriate for baking properties of flour compared to those of untreated wheat flour. The temperature at maximum viscosity increased gradually with increasing levels of chlorine. It was noted that maximum viscosity was greatly increased at 4 oz compared to those of lower levels of chlorine treatment.

• Applied Biological Chemistry
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• v.28 no.4
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• pp.278-283
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• 1985

These studies were conducted to investigate the changes and relation in protein, rheology and bread-mating properties during hard and soft wheat maturation. Samples were collected from the fields at 25 to 50 days after heading at intervals of 5 days. Protein content, sedimentation value and Pelshenke value of the tested wheat kernel or flour differed significantly between hard and soft wheat, and was relatively constant at 35 to 40 days after heading in each cultivar. In Mixogram water absorption of the flour, soft wheat increased only slightly, while intermediate and hard wheat increased remarkedly with maturation of the kernel. Total Mixogram characteristics increased and reached its maximum level at 35 days after heading. Farinogram pattern and bread loaf volume of the flour was greatly differences at the early stages of development due to cultivar, and was relatively constant at 40 days after heading. Significant positive and negative correlations were obtained among the protein and rheological properties, and tread loaf volume as the kernel matured.