Smelling in Stereo: How 3D Olfaction Processes can Revolutionize Perfumery

In numerous scientific studies, olfactory performance is operationalized as olfactoryJacques Blanc, founder, Jacques Blanc ParfumCourtesy of Jacques Blanc identification, discrimination and/or odor detection threshold¹. In this contribution, we will address olfactory threshold between traditionally formulated perfumes and newly formulated perfumes.  

Perfumers miss this challenge. Their perfumes are amazing, consumers are satisfied, but there is something missing when they want to reproduce a natural scent: a lack of veracity.  The question is: how is it that, having all the skills and ingredients, they can’t achieve this goal? The answer is so simple to state that few who hear it really believe in it. 

Let’s examine why there is always something missing with the perfumers’ traditional methods and how is it possible to reproduce the natural scent of a rose – or a garden – with a new simple process.  

the Oculus Effect: Two Versions of the Same Information 

Human beings, and animals in general, have two eyes, two ears and two nostrils. 

Why two and not only one? For survival. 

Two organs allow us to have a spatial 3D perception of our environment. For example, try to play tennis with only one eye, you’ll miss the ball.  It means we only need two slightly different versions of the same information to reproduce its volume. 

Introducing Stereo in Music

Until the 1970’s, when people used to listen to music at home, they only had one loudspeaker dispensing the music recorded by one microphone during the concert. Everybody was quite content with that. They were so satisfied that they called it Hi Fidelity. 

Then comes an innovation: stereophonic records. Two loudspeakers or earphones each dispensing at home the sounds recorded by two microphones during the concert.  

Suddenly, you have at home the magic of 3D: more depth and amazing spatialization of the instruments and the voices. The musical threshold had been improved: stereo was definitely better than mono. As a result, stereo sound has been in common use since the 1970s⁵. 

How Does 3D Work? 

Simply put, by dispensing two versions of the same information, the sound perceived by your left ear is not the same sound perceived by your right ear. Likewise, what you see with your right eye is not what you see with your left eye. And to that effect,, what you smell with your left nostril is not exactly what you smell with your right nostril. 

These tiny perceived differences of right and left (in fact two versions of the same information) are treated in your brain to create the three-dimensional effect, the volume, the depth. When you walk in nature you feel a natural sensation of an olfactory volume.  

Fig. 1: The two olfactory nervesCourtesy of Jacques Blanc

Fig. 2: View of the human olfactory bulbs in yellowCourtesy of StudyBlueWe can reproduce the same process for fragrances. The challenge is so simple that no one can understand why it has not sooner been on the market, as it has already been achieved for a long time with music and stereophony or sight and stereoscopy.

Why? The reason for this lies in the perfumer’s literature. Textbooks, and trade articles almost unanimously write that we have one olfactory bulb, one epithelium³. That’s what perfumers and student perfumers are told.  

It’s not simply an error; it’s a blunder. In fact, we do have two nostrils, two nasal cavities, two epitheliums, two olfactory bulbs (see fig. 1 and 2). And we have two olfactory nerves, just as we have for sight or hearing, each of them independent and carrying their own information into the brain which turn them into spatial information^4,6.

So, what does it change for a perfumer to know that?  Everything. 

Scent of a Rose 

Flowers have hundreds of different organic compounds. In a rose, for example, we find compounds like geraniol, citronellol, nerol, ß-damascenone, ß-ionone⁹,  all of them unequally dispersed in a space around the flower like the instruments of an orchestra in a concert hall. 

Trying to faithfully reproduce this scent with the traditional methods, perfumers will take these compounds and put them into a bottle. But by doing so, they’ve just missed the spatial distribution of the rose’s molecules in the air. This gives customers only one olfactive information, however great it is.  So far, all the perfumes in the world have been formulated in mono-olfaction, as if we only had one nostril, one olfactory bulb. 

Introducing stereOscent: Perfumer’s Innovation 

The stereOscent bottle is designed to recreate the 3D nature of scent. Courtesy of Jacques BlancSo, what to do? Should we need 100 different sprays,each spray for one molecule, coming from 100 bottles at the same time?  

No. As mentioned before, we just need two sprays – two slightly different versions of the same perfume in each spray – to allow our brain to reproduce the natural volume and depth of our rose. The same molecules, but slightly differently distributed by the means of two sprays coming from two recipients, according to a special brief.  It's a new way to formulate a perfume without changing the ingredients, nor the consumer behavior. 

How to Achieve This Challenge  

Imagine now you want to reproduce a walk along the Swiss Matterhorn mountains, Californian Salt Creek beach or Japanese Katsura Rikyu gardens. You would like to share with your clients this natural olfactive impression of a volume you’ve been missing till now.  

You may have two headspaces and record the two slightly different pieces of information, like two microphones in a concert hall. It could work, but this is not a traditional perfumer’s process. Up to now for different reasons, the creativity and imagination of a perfumer works better. The only thing you must do is to imagine what your left nostril smells by walking around, and then your right nostril. A little difference, because the scents are unequally dispersed around you: a little more narcissus on this side, a little more lavender and cedar on the other side.

Fig. 3: Diagram of stereOscent designCourtesy of Jacques Blanc

The two sprays will converge and will be partly mixed to reproduce the original 2D perfume (hatched area on fig. 3) while the two “wing” sides will each deliver a different faceted version, giving a 3D quality to your perfume. This specific spatial distribution of the molecules will add a new quality to fine fragrances: depth. Plus, this new patented process¹⁰ now allows all the perfumes to be protected, thanks to the design of an adequate spray system.  

Like a Sphere vs a Point 

stereOscent has been tested among young perfumers, with blotters turning as a windmill. Young customers are the main target because they are more open and demanding for innovation. The results are positive: “It turns around me,” said one; another said, “Compared to the stereOscent, the mono seems more squeezed, bland”; “It’s like a sphere compared to a point.”¹² 

Any perfume, existing or new, can now be formulated in 3D. It will smell like the traditional, but it will gain  depth and verticality thanks to a real spatial and temporal distribution of the ingredients. 

Just like the same jazz concert provides better feelings when listened to in stereo rather than in mono. Thus, we can say that stereOscent is a nature-like process. 

This process can be applied to functional perfumery and to flavors, and will be the subject of another contribution.  

References

1. Sorokowski P, Karwowski M, Misiak M, Marczak MK, Dziekan M, Hummel T and Sorokowska A (2019) Sex Differences in Human Olfaction: A Meta-Analysis. Front. Psychol. 10:242. doi: 10.3389/fpsyg.2019.00242
2. Harrouis, A. (2025, July 11). Portrait. François Demachy, Le Nez de la Maison Dior. Nice. https://www.nicematin.com/societe/vie-locale/portrait-francois-demachy-le-nez-de-la-maison-dior-76183  
3. Jean Claude Ellena, ‘le Parfum’, PUF, 2007, pp.19, 20 ; Brigitte Proust, ‘petite géométrie des parfums’, Sciences Seuil, 2010, pp. 12, 18. « l’odorat » La Recherche N°393, 2006,  https://www.palaisdecouverte.fr/fr/lascienceestla/dessine-moi-lessciences/la-chimie-des-odeurs/etc  
4. Wikimedia Foundation. (2025, October 21). Stereophonic sound. Wikipedia. https://en.wikipedia.org/wiki/Stereophonic_sound
5. Sobel, N., Khan, R., Saltman, A. et al. The world smells different to each nostril. Nature 402, 35 (1999). https://doi.org/10.1038/46944
6. Sanders, R. (n.d.). Two nostrils better than one, researchers show. UC Berkeley. https://newsarchive.berkeley.edu/news/media/releases/2006/12/18_scents.shtml
7. Mukherjee, S. (2017). The gene: An intimate history. Scribner.
8. Roudnitska, E. (1990). Le parfum. Presses Universitaires de France.
9. The fragrant compounds in Rose Oil. (n.d.). https://www.futurelearn.com/info/courses/everyday-chemistry/0/steps/22300
10. Patents FR1700783 ; FR2012345 ; FR1910966
11. Jacques Blanc | linkedin. (n.d.-a). https://www.linkedin.com/in/jacques-blanc-9b432611/ 
12. stereOscent is a registered trademark.