RELATIONSHIPS BETWEEN SENSORY VISCOSITY AND APPARENT VISCOSITY OF CORN STARCH PASTES

摘要

Sensory viscosity and apparent viscosity of corn starch pastes were studied at 15°, 25°, 37° and 50C, within the concentration range 0.9%-6.2%. The oral and visual sensory viscosity estimations were obtained by the converging limits method, a modified version of magnitude estimation. The exponents (perceptual growth rate) were similar (0.40 oral and 0.41 visual). No significant differences were detected between the two evaluations. Visual stimulation yielded results with a lower deviation, suggesting that this type of judgment is easier for the subject. The consistency of results obtained by the converging limits was determined by comparison of the viscosity of starch pastes with silicone oil by cross-modality matching. The ratio upper/lower limit of physical range used (13/0.03 for corn starch ～ 1100/1.80 for silicone oil) is approximately the same for both substances. This is also shown by the fact that the slope of the log-log function relating them equals 1.11 ± 0.21. No significant effect of temperature was observed on the oral viscosity estimates. The effective range of sensory viscosity for corn starch pastes was between 340 and 1300 cP.