Free sorting as a sensory research method

Understanding the consumers’ perception of fragrances

July 2009 - Market researchers of the French company ADRIANT®, a member of the European Sensory Network, have developed a method that easily allows to achieve insights into how consumers perceive multi-dimensional product categories. They show how it works by using an example from the cosmetic sector...

Developing new fragrances that fulfil the consumers’ preferences, dreams, desires, and expectations is a complex challenge for the fragrance designer. To get it right, the designer must understand precisely how consumers perceive fragrances, how they structure their fragrance world, which fragrances appeal to them, and what words consumers use to describe them. Conventional tests often do not go very far in answering these concerns.

This simple key to understanding the consumer’s perception of fragrances is called “free sorting”. Using this method, the test subject’s brain does exactly what it would naturally do to process the impressions coming out of a complex environment: it orders the various sensations and impressions into categories based on similarity. Thus it is possible to structure the world of sensations and impressions in a manner that is easily understandable.

120 female consumers took part in a case study on shower gels. The women all regularly used such products in their daily lives. In a one hour 30 minute test session, they received 15 different shower gels, all of which were described by the manufacturers as “relaxing and soothing”. The tests were conducted under standardised blind conditions using red lights so that their was no influence of the samples’ appearance on their fragrance perception.
In the first round of testing the subjects were asked to smell the samples, and then sort them according to their perceived similarities. In the next part, the women were instructed to describe the groups they had formed and explain what differentiated one group from the other. In the third and last section, a pre-formulated list of terms was handed to the subjects to help them to frame their descriptions more precisely.

Highly differentiating abilities

The results were that out of all the choices, the consumers perceived two categories of fragrances as “relaxing”: the shower gels with flowery-mild-fresh notes, and the gels with sweet-vanilla notes. On the contrary, fruity, spicy shower gels were perceived as “tonifying” and “firming”. Thus, it is clear that the consumer differentiates the fragrance world’s offerings more precisely than the descriptions on the product labels. The fragrances that were perceived as relaxing induced associations with sun, beach, tropics and exoticism or with nature. Fruity and spicy notes were more easily classified as summer fragrances, whereas flowery, fresh, and mild fragrances were associated more with spring and with a higher frequency of usage. The test subjects found some of the fragrances more suitable for children and women, whereas others had a more “manly” notes.

Perception of product categories

“The study shows that the free sorting technique is an interesting method to use in understanding the consumer’s perception of a particular product’s category,” says the case study leader, ADRIANT’s Lise Dreyfuss; “In the case of the shower gels that were tested, we have found that consumers who were offered products that were advertised as “relaxing and soothing” had highly differentiated perceptions of the products, and “transposed” the producers’ respective product descriptions into different olfactory notes. The next step would be to make the connection between the consumer’s perceptions and the professionals’ characterisation of the product. Only then will the fragrance designer be able to create fragrances that reach the consumer as targeted messages that are truly understood as they are meant to be understood.”

The free sorting method is especially suited for clarifying how consumers perceive such multi-dimensional product descriptions as “energizing” or “care”. Such terminology is not limited to the cosmetic industry; it is also popular in the food sector – for instance when a product is advertised as “aromatic”, “fresh”, or “healthy”. Here too, it is worthwhile to use free sorting as a research method…   


Senior Project Manager


Free sorting in sensory research 

  • the free sorting of products as to their similarity is an easier task than comparing the features of individual products,
  • does not cause problems when testing larger numbers of products,
  • allows the screening of market and product positioning completely from the perspective of the consumer,
  • spotlights which difference and which similarity is perceived by the consumer, and what terms they use to describe these sensory impressions,
  • makes it possible to identify potential consumer sub-groups by the way in which they perceive, and thus better understand the “individual” reactions,
  • makes it possible to identify the key sensory, usage and symbolic characteristics that help the consumer to understand and sort the market
  • creates the prerequisites for a comparison between professional and layman classifications