The Impact of Colour on Olfactory Perceptions of Binary Fragrance Mixtures

This work forms part of a broader investigation into how colour influences odour perception. In each study, cis-3-hexenol is paired with a different odour molecule, using both equal and varying intensity combinations to examine the impact of colour cues on olfactory experience.

In the cosmetics industry, significant attention is given to sensorial aspects of products to enhance consumer satisfaction alongside product effectiveness. Consumers often assess the quality and appeal of a product through tactile experiences, such as evaluating its texture and fulfilling haptic desires. Given the existence of data highlighting cross-modal effects and effective applications between colour and odour, these sensory components are important to consider for personal care products. Fragrance, in particular, has psychophysiological effects and can positively influence mood, making it a valuable addition to cosmetic products.
 
Previous research has shown that colour can influence perceived odour intensity, particularly in binary mixtures matched for perceptual strength. However, these findings were limited to a single odourant pair, isobornyl cyclohexanolloandolimonene, and did not consider how perceived intensity asymmetries might affect colour-odour interactions.

The present study extends this work by testing additional odourants, citronellol and cis-3-hexenol, and examining colour effects across three mixture types. These include a perceptually balanced 1:1 blend and two unbalanced mixtures where one component dominates. This design enables investigation of colour’s role in modulating perception under varying odour dominance, contributing to a more nuanced understanding of multisensory integration.