What does Clean Really Smell Like? Designing Studies to Evaluate the Odour Removal Efficacy of Laundry Detergents Designed for Cold Wash

New laundry detergents are designed to be efficient at low temperatures, aiming to preserve textiles and reduce energy consumption. To demonstrate their effectiveness in removing sweat malodours, reliable and discriminating evaluation methods are needed. This study explores the impact of several experimental parameters on the assessment of malodour removal performance, including fabric composition (cotton vs polyester), post-wash evaluation stage (damp vs dry) or malodour origin (in vivo vs in vitro approach). Using both wear-and-wash and in vitro protocols, malodour and fragrance intensities were evaluated by a trained sensory panel. The results underline the importance of careful test design to accurately differentiate product performance, highlighting key methodological choices for future test protocols.