The hidden science of haptics: A pedagogical review of tactile evaluation in cosmetics.

Sensory analysis is a cornerstone of cosmetic development, yet remains underrepresented in peer-reviewed literature due to its frequent confinement to internal or industrial use, unlike food science, where shared methodologies foster wider academic development. This review explores the multiple dimensions of haptics as tactile sensory analysis in cosmetics, underscoring its central role in product development. The skin, as the primary organ of touch, is examined in detail, along with the eye, which plays a secondary role in the perception of cosmetic products. Particular emphasis is placed on the biological mechanisms underpinning sensory evaluation, especially the role of mechanoreceptors and photoreceptors in stimulus detection, neural transmission and sensory response generation. These responses, evaluated by expert assessors, form the basis of standardized sensory protocols. The review covers key methodologies, from discriminatory and hedonic tests to descriptive sensory analysis, each with its strengths and limitations. Conventional sensory profiling remains robust but time- and resource-intensive, prompting interest in faster alternatives such as free-choice profiling or flash profiling. While more flexible, these methods pose challenges in terms of variability and data interpretation. Instrumental techniques, such as texture analysis, rheology and biometrological approaches, are increasingly integrated as proxies to provide quantitative data that correlate with standardized sensory evaluations. These tools enhance analytical accuracy and enable product testing in contexts where human trials may not be feasible. Finally, the review highlights emerging innovations: virtual and augmented reality, artificial intelligence and electronic sensing devices are reshaping the landscape of sensory evaluation. These technologies support predictive modelling and objective assessment, though their implementation raises new challenges, including the artificial modulation of perception and environmental control. This pedagogical review provides a comprehensive overview of tactile sensory analysis in cosmetics, bridging traditional methods with cutting-edge innovations and offering guidance for future research and application.