Dynamic sensory characterization of cosmetic creams during application using Temporal Check-All-That-Apply (TCATA) questions

The evolution of sensory characteristics during the application of cosmetic creams has been long recognized as important. However, standard methodologies do not evaluate how sensory characteristics of products change during application, and do not determine the onset of specific sensations. In this manuscript, a new temporal methodology, Temporal Check-All-That-Apply (TCATA), is used to enable characterization of the dynamic sensory properties of cosmetic creams during application. Six cosmetic emulsions were evaluated by 22 semi-trained assessors in duplicate using TCATA. Nine sensory attributes were considered: sticky, difficult to spread, easy to spread, white residue, fresh, smooth, waxy, greasy, and oily. Data were analyzed using line plots, difference curves, and correspondence analysis. The temporal profiles of the products during application were determined and fitted expectations due to changes in their rheological properties, water evaporation, and absorption into the stratum corneum of the skin, which cause changes in the structure of the film of product left on the skin. Differences in the temporal profiles of the samples were identified and explained by differences in their formulations, which indicates the validity of the data collected using TCATA with semi-trained assessors. These results show the potential of TCATA for characterizing the dynamic sensory profile of cosmetic creams during application, which opens new possibilities to sensory characterization of other cosmetic products. (C) 2015 Elsevier Ltd. All rights reserved.