Influence of fading duration on TCATA evaluation

Abstract

Temporal Check All that Apply (TCATA) is a dynamic sensory evaluation technique in which participants select the terms they consider apply at each moment from a list of attributes and deselect them when they no longer apply. TCATA Fading is a variant that facilitates the TCATA task by making term deselection automatic and progressive over a period of a few seconds. The aim of the present work was to assess the influence of fading duration on the TCATA Fading task and results. Three studies evaluated two fading durations (4 s vs 8 s in Study 1 and 2, and 3 s vs 6 s in Study 3), using commercial cooked ham, a strawberry-flavoured dessert and orange juice, and compared task performance, TCATA curves and sensory trajectories. Longer fading times resulted in TCATA curves with higher citation proportions, in which differences among samples lasted slightly longer. TCATA curves and trajectories provided very similar information on differences in dynamic sensory perception of the products. Fading duration seems to be not critical when using values within a “reasonable” range, which can be determined in preliminary essays. Ideally it would be advisable to choose the shorter fading time in the range to avoid possible overestimation of the duration of sensations and “filling gaps” procedure to compensate the increase in gap events due to delay in reselection. This is the first paper to show the implications of duration of fading in TCATA evaluation.