If you heard that a scent you liked was “made from natural ingredients,” would you like it even more? Conversely, would your impression of it become less favorable if you heard that it was “made using biocatalysis or biotechnology”?
A 2023 study investigated how these explanations of origin relate to evaluations of scents. The background is a move to reconsider fragrance production methods from an environmental perspective. Even if new production methods could be useful, they are unlikely to become widespread without consumer acceptance. The researchers therefore conducted an experiment to examine how closely perceiving a scent as natural is linked to liking it.
Comparing materials and descriptions separately, even for scents with the same name
The experiment, conducted in Switzerland, involved 193 participants. Three scents were used: bergamot, rose, and sandalwood. For each, there was a sample made with a natural essential oil or absolute, and another sample made by combining its main components to create a similar scent. The latter included molecules derived from biocatalysis or biotechnology.
Biocatalysis is a method of promoting chemical reactions by using biological activity, such as that of enzymes. Here, scents extracted directly from natural raw materials were compared with reconstructed scents containing components made using these technologies. This does not mean that every component of the reconstructed scents was made by the same process.
Participants were randomly assigned to groups that smelled either the natural samples or the reconstructed samples, and were further divided into groups that were or were not informed of the samples’ origin. When information was provided, the natural-sample group was told that the samples were made from natural ingredients, while the reconstructed-sample group was told that they were made in a laboratory using biocatalysis or industrial biotechnology.
All participants smelled the three scents in sequence on paper smelling strips and rated aspects including liking, intensity, perceived naturalness, pleasantness, and attractiveness. Even though the natural and reconstructed samples were intended to have the same scent, their actual compositions differed. Differences between the samples and the effects of explaining their origin need to be considered separately.
Higher perceived naturalness does not consistently mean greater liking
The natural samples were rated as more natural when participants were informed of their origin. However, that information did not consistently increase liking or pleasantness. Perceiving something as natural and liking it did not necessarily move in the same direction.
For the reconstructed samples, too, the results did not show a consistent decline in ratings when the production method was explained. Across the conditions with and without information, the reconstructed samples used in this study received higher ratings for liking and pleasant impressions than the natural samples. This was a comparison of the samples that participants actually smelled; it does not mean that the words “bio-based” alone increased liking.
Intensity ratings differed by scent, but there were no significant effects of origin or of information about it. Thus, this experiment did not consistently reproduce the effect reported in earlier research that “a scent is liked more when people are told it is natural.”
Can information about production methods and the environment change opinions?
After evaluating the scents, all participants read an explanatory text about the environmental impacts of producing natural ingredients and about production methods using biocatalysis. In the subsequent responses, the importance placed on using natural ingredients in fragrances was reported to have fallen from an average of 2.8 to 2.2 on a four-point scale. The authors also reported that ratings of how environmentally friendly the production of natural ingredients was fell after the text, while there was no clear change in the ratings for biocatalysis.
However, this before-and-after comparison has an important limitation. Of the 193 participants, 62 said that reading the explanation had not changed their minds, so the researchers did not ask them to rate the items again and instead used their initial scores as their later scores. The authors acknowledge that this approach could not account for variability arising from answering again, and that the results need to be interpreted cautiously. There was also no control group that did not read the explanatory text.
These figures alone therefore do not establish that the explanation changes opinions by a particular amount, or that reading it weakens everyone’s preference for natural ingredients. Even so, the results point toward further testing of how people consider their preferences alongside specific information about production methods, rather than just labels describing origin.
Why did the findings differ from earlier research?
The authors suggest several possibilities. The reconstructed scents may have been more familiar because they were closer to impressions people had experienced in commercial fragrances. Also, the term “bio” used in this study can evoke organic products in German-speaking regions, which may have weakened negative impressions of the technology. Neither explanation was established by this study alone.
The participants had volunteered for an experiment at a technical university, and their mean age was 32. The sample may have been biased toward people with a strong interest in science or scents. The experiment did not involve choosing a finished perfume together with its branding and packaging. Instead, participants smelled three relatively simple scents in a fixed order: bergamot, rose, and sandalwood. Purchasing behavior and continued use were not measured either.
The words that participants associated with the scents also included places and memories, which did not fit into ingredient names or perfumery classifications. The authors draw attention to differences between experts’ descriptions of scents and consumers’ perceptions. Their view is that understanding evaluations and choices requires investigating not only origin, but also familiarity, personal experience, and the purpose of the choice.
The study’s acknowledgments and competing-interest declaration state that one of the authors received funding through a Junior Fellowship from Collegium Helveticum.
Summary
Telling participants that a scent was natural increased its perceived naturalness, but did not necessarily increase liking consistently. The participants in this study also did not consistently reject production methods using biocatalysis and related technologies. The authors believe there is scope for consumers to accept new fragrance production methods.
The resulting proposal is to communicate transparently what is being made and how, rather than relying solely on a “natural” label. However, this experiment did not measure whether the actual environmental impacts of the individual samples were lower. The next steps are to explain the advantages of production methods with supporting evidence, and to examine how they are received by more diverse people and in real choices involving packaging and brands.
References
Michailidou, F., Bearth, A., Deilmann, C., & Siegrist, M. (2023). Scent and sustainability: investigating consumer evaluations of biocatalysis and naturalness in fragrances. Food Quality and Preference, 111, 104994. DOI: 10.1016/j.foodqual.2023.104994 / Original paper archived by ETH Zurich.
© 2023 The Authors. Published by Elsevier Ltd. Original article license: CC BY 4.0.
