DETERMINATION OF PRACTICALLY SIGNIFICANT DIFFERENCES IN THE SENSORILY PERCEIVED CONSISTENCY OF SEMILIQUID FOODS

摘要

The consistency of commercial salad dressing, chocolate pudding and mustard samples before and after controlled disruption was assessed by squeezing flow viscometry and evaluated sensorily by an untrained panel. The instrumental parameters were the apparent stress at 1.5 and 1.0 mm height and the apparent residual stress after 60 and 120 s relaxation (at 1.0 mm height). The panelists were asked to identify the sample(s) with the stronger consistency in a triangular test. The percent correct identifications was plotted against the difference in the magnitude of the instrumental parameters and their ratios. The scatter of these plots suggests that the effective stimulus for consistency perception was primarily the overall resistance to deformation or flow and to a much lesser extent to more subtle rheological characteristics like the 'degree of solidity'. In the range of consistencies examined, the detection thresholds were on the order of 0.5-0.7 kPa and 0.4-0.6 kPa at 1.0 and 1.5 mm height, respectively. They corresponded to stress ratios on the order of 0.75-0.85. Results of this kind will enable setting objective standards for the consistency of commercial semi liquid foods and tolerance margins to deviations from them.