Sunscreen Sensory Attribute Prediction via Textural, Rheological, and Tribological Tests

This study aims to find the quick ways to predict sensorial attributes of sunscreens using instrumental measurements. We specifically focus on the attributes most rele- vant to consumer “liking” and the easiest measurements to implement in industrial labs for product development. Of the latter, we consider three types of measurements: emulative “textural” tests typically performed with a texture analyzer as well as rheo- logical and tribological measurements. Textural tests are generally preferred but may be paralleled by rheological measurements provided they are implementable on simple viscometers used in industry (albeit with additional data processing). We found that both textural and simple rheological/viscometrical tests work well for predicting sen- sorial attributes about flow before (thickness) and during (spreadability) application of the products. Tribology provides useful additional information for the latter but is primarily useful for after-feel or residue attributes (absorption and skin stickiness). These findings show that simple lab tests relying on these techniques can predict hu- man sensory attributes, thus efficiently guiding product developers while reducing the need for costly and time-consuming panel studies.