Tag Archives: smell

Fragrance design using deep neural networks (DNNs)

A December 31, 2024 news item on ScienceDaily announces work from Japanese researchers on fragrance design,

Scientific research explores the potential of DNNs [deep neural networks] in transforming fragrance design. By analyzing the sensing data of 180 essential oils, the DNN was trained using the odor descriptor data from 94 essential oils to generate fragrance profiles, validated through sensory evaluations to align with human olfactory perceptions. The study underscores the technological ability to streamline fragrance creation, reduce costs, and foster innovation, opening up exciting possibilities for personalized and scalable scent development.

Caption: DNNs can transform fragrance design by predicting and creating novel scents from chemical data, ushering in a new era of digital scent creation. Credit: Institute of Science Tokyo

A January 9, 2025 Institute of Science Tokyo press release (also on EurekAlert but published December 31, 2024), which originated the news item, delves further into the topic of digitizing the sense of smell, Note: A link has been removed,

Deep Neural Networks (DNNs) have become an essential driver of innovation across various industries, from healthcare to manufacturing. By analyzing large datasets, identifying patterns, and making precise predictions, DNNs are transforming the way we approach complex tasks. One such area where DNNs are making a remarkable impact is in the digitalization of smell, a field traditionally dominated by human expertise and sensory evaluations. However, a recent study aims to revolutionize this practice by exploring how DNNs can assist in fragrance design.

Moreover, an odor reproduction technique has been developed, enabling a wide variety of scents to be generated by varying the mixing ratio of a small set of odor components. These odor components are prepared by blending essential oils used in the analysis.

A research team led by Professor Takamichi Nakamoto from the Laboratory for Future Interdisciplinary Research of Science and Technology (FIRST), Institute of Integrated Research (IIR), Institute of Science Tokyo, Japan, published their research in Scientific Reports on December 28. This study was driven by the growing need for more efficient and innovative methods of fragrance creation. The study aimed to quickly make the intended scent without trial and error, leveraging DNNs to predict odor profiles based on multidimensional sensing data.

Nakamoto explains “We hypothesized that the DNNs when integrated with chemistry and sensory science could offer new insights into fragrance development. We conducted the study by analyzing mass spectrometry data from 180 essential oils, providing a comprehensive understanding of their odor components. These data were then used to train a DNN designed to predict odor descriptors from the odor-component composition. The DNN employed multiple layers optimized to capture the intricate relationships between its compositions and the resulting scents.” To improve the model’s accuracy and generalization, the team augmented the data with random mixtures of essential oil spectra and introduced noise, ensuring the model could adapt to real-world complexities. Once the DNN model generated the odor-component compositions, human evaluators assessed the DNN- generated scents alongside reference oils.

The DNN achieved the highest accuracy in predicting the odor descriptor “floral” and lower accuracy for the descriptor “woody”. Sensory testing further confirmed the effectiveness of the model, as human panelists found that the DNN-generated oils using odor components were more similar to the reference oils than those with added odor descriptors. These findings highlight the system capability to accurately replicate existing fragrance profiles and, in some cases, generate entirely new combinations.

The study demonstrates numerous benefits, like DNN can significantly reduce the time and costs involved in fragrance development by streamlining both chemical analysis and sensory evaluations. Additionally, DNN makes fragrance creation scalable, allowing it to adapt to diverse market preferences and consumer demands. Most notably, the use of DNN opens up innovative possibilities by enabling the generation of new and unique scent profiles that might not have been discovered through traditional methods.

Looking to the future, the implications of this study are profound. “As DNN models continue to evolve, they could enable the creation of personalized fragrances tailored to individual preferences. Additionally, this approach could be extended to other sensory domains, such as taste, where similar methods could be used to craft personalized flavor profiles,” shares Nakamoto.

By combining DNNs, chemical analysis, and sensory testing, the study emphasizes the potential to replicate and innovate within the fragrance industry. With its ability to enhance efficiency and creativity, a revolution in fragrance design is expected, ushering in a new era of innovation.


About Institute of Science Tokyo (Science Tokyo)

Institute of Science Tokyo (Science Tokyo) was established on October 1, 2024, following the merger between Tokyo Medical and Dental University (TMDU) and Tokyo Institute of Technology (Tokyo Tech), with the mission of “Advancing science and human wellbeing to create value for and with society.”

Here’s a link to and a citation for the paper,

Automatic scent creation by cheminformatics method by Manuel Aleixandre, Dani Prasetyawan & Takamichi Nakamoto. Scientific Reports volume 14, Article number: 31284 (2024) DOI: https://doi.org/10.1038/s41598-024-82654-7 Published: 28 December 2024

This paper is open access.

Olfactory ethics

Smell is a very charged topic as I learned almost 20 years ago when working on a master’s programme on creating writing and digital technology via distance education. I had innocently suggested that we include the sense of smell when looking at immersive technology.

One of the members in our group of three ‘blew up’. As someone who had led the Irish teams involved in Microsoft’s multimedia efforts, he asserted his superior understanding of multimedia and narrative. Never one to go away quietly, I persisted, as did the other member of our group, in the discussion.

The whole thing culminated in three projects where our ‘expert’ colleague titled his project ‘STFU’. It was a several minute video diatribe starting with the words ‘shut the …’ You can probably fill in the blanks.

It seems that smell is a very charged topic when applied to creative writing and/or literature. Amelia Louks, research supervisor in English literature at the University of Cambridge, writes about her experience with smell and literature in a December 16, 2024 essay on The Conversation, Note: Links have been removed,

In November [2024], I celebrated finishing my PhD. After three and a half years of writing and research, it was an occasion I wanted to share with my academic network, so I posted a photo of myself holding a physical copy of my PhD thesis on X. The post amassed 120 million views and sparked a lot of anger in response to its title: Olfactory Ethics: The Politics of Smell in Modern and Contemporary Prose.

The title received criticism from those who were wilfully misrepresenting the nature of the research. “Smells are racist,” became a misguided refrain. One user commented that it was a study of “why it’s racist and/or classist to not like it when people exhibit body odors consistent with poor hygiene”.

My thesis studies how certain authors of the past century used smell in literature to indicate social hostilities, such as prejudice and exploitation. It also connects this to our real-world understanding of the role the sense plays in society.

For instance, in The Road to Wigan Pier (1936), George Orwell states that “the real secret of class distinctions in the West” can be summed up in four frightful words: “The lower classes smell.” Orwell proceeds to unpick the harm that this kind of messaging causes and how we might combat it.

It is well documented that smell has been used as a justification for expressions of racism, classism and sexism. Since the 1980s, researchers have been assessing the moral implications of perceptions and stereotypes related to smell.

My thesis adds to this work by assessing the contributions of a selection of books and films that take smell seriously. In each of the texts I considered, smell takes on a role beyond mere sense perception.

I include examples from well-known works by George Orwell, Vladimir Nabokov, J.M. Coetzee and Toni Morrison, as well as notable recent examples, such as Bong Joon-ho’s film, Parasite.

Sheena Goodyear’s December 5, 2025 Canadian Broadcasting Corporation (CBC) article based on the interview conducted with Louks for the CBC/s As It Happens radio programme delves further into Louks’ experience with posting about her PhD and how she responded to the barrage,

When Ally Louks posted last week that she was “PhDone” with her English literature thesis, she didn’t expect to find herself at the centre of a culture war.

Louks posted a picture of herself on X, formerly known as Twitter, smiling proudly and holding a bound copy of her University of Cambridge thesis on the “politics of smell” in literature. 

One week later, the seemingly innocuous post has been viewed 117.1 million times, made headlines around the world, and put Louks on the receiving end of plenty of praise but also heaps of hate, including a rape threat that’s now under investigation by police.

“I couldn’t possibly have anticipated that this post would even go beyond my little academic community on Twitter of about 200 people,” Louks told As It Happens host Nil Köksal. 

At the heart of the backlash is the title of Louks’s thesis, visible in the photo: “Olfactory Ethics: The Politics of Smell in Modern and Contemporary Prose.”

CBC reviewed dozens of comments on the post, many from men saying the topic was too “woke,” or a waste of time and money. Others suggested women don’t belong in academia.

“What a stupid f–king thing to ‘study,'” wrote one person. 

“You have made no valuable contributions in your thesis, and perhaps in your entire life,” wrote another. 

“You would have spent your years better by getting married and having children,” someone else posted.

Louks says she doesn’t take it personally. 

“I do think that it’s clear that misogyny is at play [emphasis mine], especially since I’m a young and high achieving woman,” she said.

“But I also think there’s a kind of broader arc here going on about people questioning the value of literary study and of the humanities and, indeed, of academia [emphases mine].”

Louks says she decided not to lock her account or take the post down. She also isn’t squabbling with commenters.

“I didn’t want them to think that they’d chased me off or that they’d affected me in any way because they truly haven’t,” she said. “I do feel safe.”

he barrage of hate, she says, was quickly followed by a surge of support. 

“This has been a bit of a case study in how we present ourselves online,” she said.

“Being polite and respectful has actually done something kind of magical here in that so many people have rallied around me and supported me just because I didn’t stoop to the level of the online trolls.”

May you experience the freedom to explore even topics that seem obscure.

Preserving heritage smells (scents)

Preserving a smell? It’s an intriguing idea and forms the research focus for scientists at the University College London’s (UCL) Institute for Sustainable Heritage according to an April 6, 2017 Biomed Central news release on EurekAlert,

A ‘Historic Book Odour Wheel’ which has been developed to document and archive the aroma associated with old books, is being presented in a study in the open access journal Heritage Science. Researchers at UCL Institute for Sustainable Heritage created the wheel as part of an experiment in which they asked visitors to St Paul’s Cathedral’s Dean and Chapter library in London to characterize its smell.

The visitors most frequently described the aroma of the library as ‘woody’ (selected by 100% of the visitors who were asked), followed by ‘smoky’ (86%), ‘earthy'(71%) and ‘vanilla’ (41%). The intensity of the smells was assessed as between ‘strong odor’ and ‘very strong odor’. Over 70% of the visitors described the smell as pleasant, 14% as ‘mildly pleasant’ and 14% as ‘neutral’.

In a separate experiment, the researchers presented visitors to the Birmingham Museum and Art Gallery with an unlabelled historic book smell – sampled from a 1928 book they obtained from a second-hand bookshop in London – and collected the terms used to describe the smell. The word ‘chocolate’ – or variations such as ‘cocoa’ or ‘chocolatey’ – was used most often, followed by ‘coffee’, ‘old’, ‘wood’ and ‘burnt’. Participants also mentioned smells including ‘fish’, ‘body odour’, ‘rotten socks’ and ‘mothballs’.

Cecilia Bembibre, heritage scientist at UCL and corresponding author of the study said: “Our odour wheel provides an example of how scientists and historians could begin to identify, analyze and document smells that have cultural significance, such as the aroma of old books in historic libraries. The role of smells in how we perceive heritage has not been systematically explored until now.”

Attempting to answer the question of whether certain smells could be considered part of our cultural heritage and if so how they could be identified, protected and conserved, the researchers also conducted a chemical analysis of volatile organic compounds (VOCs) which they sampled from books in the library. VOCs are chemicals that evaporate at low temperatures, many of which can be perceived as scents or odors.

Combining their findings from the VOC analysis with the visitors’ characterizations, the authors created their Historic Book Odour wheel, which shows the chemical description of a smell (such as acetic acid) together with the sensory descriptions provided by the visitors (such as ‘vinegar’).

Cecilia Bembibre said: “By documenting the words used by the visitors to describe a heritage smell, our study opens a discussion about developing a vocabulary to identify aromas that have cultural meaning and significance.”

She added: “The Historic Book Odour Wheel also has the potential to be used as a diagnostic tool by conservators, informing on the condition of an object, for example its state of decay, through its olfactory profile.”

The authors suggest that, in addition to its use for the identification and conservation of smells, the Historic Book Odour Wheel could potentially be used to recreate smells and aid the design of olfactory experiences in museums, allowing visitors to form a personal connection with exhibits by allowing them to understand what the past smelled like.

Before this can be done, further research is needed to build on the preliminary findings in this study to allow them to inform and benefit heritage management, conservation, visitor experience design and heritage policy making.

Here’s what the Historic Book Odour Wheel looks like,

Odour wheel of historic book containing general aroma categories, sensory descriptors and chemical information on the smells as sampled (colours are arbitrary) Courtesy: Heritage Science [downloaded from https://heritagesciencejournal.springeropen.com/articles/10.1186/s40494-016-0114-1

Here’s a link to and a citation for the paper,

Smell of heritage: a framework for the identification, analysis and archival of historic odours by Cecilia Bembibre and Matija Strlič. Heritage Science20175:2 DOI: 10.1186/s40494-016-0114-1 Published: 7 April 2017

©  The Author(s) 2017

This paper is open access.

Scented video games: a nanotechnology project in Europe

Ten years ago when I was working on a master’s degree (creative writing and new media), I was part of a group presentation on multimedia and to prepare started a conversation about scent as part of a multimedia experience. Our group leader was somewhat outraged. He’d led international multimedia projects and as far as he was concerned the ‘scent’ discussion was a waste of time when we were trying to prepare a major presentation.

He was right and wrong. I think you’re supposed to have these discussions when you’re learning and exploring ideas but, in 2006, there wasn’t much work of that type to discuss. It seems things may be changing according to a May 21, 2016 news item on Nanowerk (Note: A link has been removed),

Controlled odour emission could transform video games and television viewing experiences and benefit industries such as pest control and medicine [emphasis mine]. The NANOSMELL project aims to switch smells on and off by tagging artificial odorants with nanoparticles exposed to electromagnetic field.

I wonder if the medicinal possibilities include nanotechnology-enabled aroma therapy?

Getting back to the news, a May 10, 2016 European Commission press release, which originated the news item, expands on the theme,

The ‘smellyvision’ – a TV that offers olfactory as well as visual stimulation – has been a science fiction staple for years. However, realising this concept has proved difficult given the sheer complexity of how smell works and the technical challenges of emitting odours on demand.

NANOSMELL will specifically address these two challenges by developing artificial smells that can be switched on and off remotely. This would be achieved by tagging specific DNA-based artificial odorants – chemical compounds that give off smells – with nanoparticles that respond to external electromagnetic fields.

With the ability to remotely control these artificial odours, the project team would then be able to examine exactly how olfactory receptors respond. Sensory imaging to investigate the patterns of neural activity and behavioural tests will be carried out in animals.

The project would next apply artificial odorants to the human olfactory system and measure perceptions by switching artificial smells on and off. Researchers will also assess whether artificial odorants have a role to play in wound healing by placing olfactory receptors in skin.

The researchers aim to develop controllable odour-emitting components that will further understanding of smell and open the door to novel odour-emitting applications in fields ranging from entertainment to medicine.

Project details

  • Project acronym: NanoSmell
  • Participants: Israel (Coordinator), Spain, Germany, Switzerland
  • Project Reference N° 662629
  • Total cost: € 3 979 069
  • EU contribution: € 3 979 069
  • Duration:September 2015 – September 2019

You can find more information on the European Commission’s NANOSMELL project page.

For the smell of it

Having had a tussle with a fellow student some years ago about what constituted multimedia, I wanted to discuss smell as a possible means of communication and he adamantly disagreed (he won),  these  two items that feature the sense of smell  are of particular interest, especially (tongue firmly in cheek) as one of these items may indicate I was* ahead of my time.

The first is about about a phone-like device that sends scent (from a Feb. 11, 2014 news item on ScienceDaily),

A Paris laboratory under the direction of David Edwards, Michigan Technological University alumnus, has created the oPhone, which will allow odors — oNotes — to be sent, via Bluetooth and smartphone attachments, to oPhones across the state, country or ocean, where the recipient can enjoy American Beauties or any other variety of rose.

It can be sent via email, tweet, or text.

Edwards says the idea started with student designers in his class at Harvard, where he is a professor.

“We invite young students to bring their design dreams,” he says. “We have a different theme each year, and that year it was virtual worlds.”

The all-female team came up with virtual aromas, and he brought two of the students to Paris to work on the project. Normally, he says, there’s a clear end in sight, but with their project no one had a clue who was going to pay for the research or if there was even a market.

A Feb. 11, 2014 Michigan Technological University news release by Dennis Walikainen, which originated the news item, provides more details about the project development and goals,

“We create unique aromatic profiles,” says Blake Armstrong, director of business communications at Vapor Communications, an organization operating out of Le Laboratorie (Le Lab) in Paris. “We put that into the oChip that faithfully renders that smell.”

Edwards said that the initial four chips that will come with the first oPhones can be combined into thousands different odors—produced for 20 to 30 seconds—creating what he calls “an evolution of odor.”

The secret is in accurate scent reproduction, locked in those chips plugged into the devices. Odors are first captured in wax after they are perfected using “The Nose”– an aroma expert at Le Lab, Marlène Staiger — who deconstructs the scents.

For example, with coffee, “the most universally recognized aroma,” she replaces words like “citrus” or “berry” with actual scents that will be created by ordering molecules and combining them in different percentages.

In fact, Le Lab is working with Café Coutume, the premier coffee shop in Paris, housing baristas in their building and using oPhones to create full sensory experiences.

“Imagine you are online and want to know what a particular brand of coffee would smell like,” Edwards says. “Or, you are in an actual long line waiting to order. You just tap on the oNote and get the experience.”

The result for Coutume, and all oPhone recipients, is a pure cloud of scent close to the device. Perhaps six inches in diameter, it is released and then disappears, retaining its personal and subtle aura.

And there other sectors that could benefit, Edwards says.

“Fragrance houses, of course, culinary, travel, but also healthcare.”

He cites an example at an exhibition last fall in London when someone with brain damage came forward. He had lost memory, and with it his sense of taste and smell.  The oPhone can help bring that memory back, Edwards says.

“We think there could be help for Alzheimer’s patients, related to the decline and loss of memory and olfactory sensation,” he says.

There is an image accompanying the news release which I believe are variations of the oPhone device,

Sending scents is closer than you think. [downloaded from http://www.mtu.edu/news/stories/2014/february/story102876.html]

Sending scents is closer than you think. [downloaded from http://www.mtu.edu/news/stories/2014/february/story102876.html]

You can find David Edwards’ Paris lab, Le Laboratoire (Le Lab), ici. From Le Lab’s homepage,

Opened since 2007, Le Laboratoire is a contemporary art and design center in central Paris, where artists and designers experiment at frontiers of science. Exhibition of works-in-progress from these experiments are frequently first steps toward larger scale cultural humanitarian and commercial works of art and design.

 

Le Laboratoire was founded in 2007 by David Edwards as the core-cultural lab of the international network, Artscience Labs.

Le Lab also offers a Mar. ?, 2013 news release describing the project then known as The Olfactive Project Or, The Third Dimension Global Communication (English language version ou en français).

The second item is concerned with some research from l’Université de Montréal as a Feb. 11, 2014 news item on ScienceDaily notes,

According to Simona Manescu and Johannes Frasnelli of the University of Montreal’s Department of Psychology, an odour is judged differently depending on whether it is accompanied by a positive or negative description when it is smelled. When associated with a pleasant label, we enjoy the odour more than when it is presented with a negative label. To put it another way, we also smell with our eyes!

This was demonstrated by researchers in a study recently published in the journal Chemical Senses.

A Feb. 11, 2014 Université de Montréal news release, which originated the news item, offers details about the research methodology and the conclusions,

For their study, they recruited 50 participants who were asked to smell the odours of four odorants (essential oil of pine, geraniol, cumin, as well as parmesan cheese). Each odour (administered through a mask) was randomly presented with a positive or negative label displayed on a computer screen. In this way, pine oil was presented either with the label “Pine Needles” or the label “Old Solvent”; geraniol was presented with the label “Fresh Flowers” or “Cheap Perfume”; cumin was presented with the label “Indian Food” or “Dirty Clothes; and finally, parmesan cheese was presented with the label of either the cheese or dried vomit.

The result was that all participants rated the four odours more positively when they were presented with positive labels than when presented with negative labels. Specifically, participants described the odours as pleasant and edible (even those associated with non-food items) when associated with positive labels. Conversely, the same odours were considered unpleasant and inedible when associated with negative labels – even the food odours. “It shows that odour perception is not objective: it is affected by the cognitive interpretation that occurs when one looks at a label,” says Manescu. “Moreover, this is the first time we have been able to influence the edibility perception of an odour, even though the positive and negative labels accompanying the odours showed non-food words,” adds Frasnelli.

Here’s a link to and a citation for the paper,

Now You Like Me, Now You Don’t: Impact of Labels on Odor Perception by  Simona Manescu, Johannes Frasnelli, Franco Lepore, and Jelena Djordjevic. Chem. Senses (2013) doi: 10.1093/chemse/bjt066 First published online: December 13, 2013

This paper is behind a paywall.

* Added ‘I was’ to sentence June 18, 2014. (sigh) Maybe I should spend less time with my tongue in cheek and give more time to my grammar.