Comparing touch senses of naïve and expert panels through treated hair swatches: which associated wordings correlate with hair physical properties?

Objectives This study (i) compared the sense of touch between a naive and expert panels, under visual or blind conditions, using differently treated hair swatches and (ii) explored possible common wordings used by both panels and their possible links with some physical properties of hairs. Methods Two sets of 15 hair swatches of Caucasian and Chinese origins were differently treated (bleached, permed, brushed, etc.) or organized (root–tip vs. tip–root). These were evaluated by tactile assessments by two panels (105 naive consumers and 10 hair experts) under visual or blind conditions, in two geographical locations. A series of 17 defined antonym adjectives, as descriptors, allowed responses of each panel to being scored and their preference mappings to being defined on a like–dislike scale. Hair swatches were measured and assessed by various instrumental techniques (bending, diameter, cuticle cohesion, alignments of hair). Results Apart from a few overlaps, all 15 hair swatches were well differentiated by both panels which showed a global agreement, making experts reliable assessors. Only three descriptors among 17 correlated with some objective measurements. Tactile-visual assessments differ from those performed tactile blind in both panels. Agreements between both panels appear, however, closer under tactile-blind conditions. Conclusion Trained hair experts were confirmed as reliable representatives of a larger and naive cohort, viewed as consumers. Hair swatches were well differentiated by both panels, with comparable descriptor rankings.