One of the key challenges to predict odor from the molecular structure is unarguably our limited understanding of the odor space and the complexity of the underlying structure-odor relationships. Here, we introduce an expert-curated taxonomy (ET) that captures the hierarchical relations between odor descriptors for molecular datasets. To quantify the usefulness and relevance of this expert taxonomy, we provide a systematic validation that leverages the predictive performance of machine learning models for structure-based odor predictions, as well as known structure-odor relationships. As a control next to the ET based on semantic and perceptual similarities, we provide a data-driven taxonomy (DT) based on clustering co-occurrence patterns of odor descriptors from our expert-curated molecular dataset. The latter is derived from available datasets in the Pyrfume repository. Both taxonomies (ET and DT) add value in the semantic organization of odor descriptors and provide an avenue for novel insights in molecular structure-odor prediction. Together with in-depth validation steps that highlight the value of odor taxonomies, the quality of the ET is quantitatively assessed. The DT further allows critical evaluation of the expert taxonomy, identification of potential inconsistencies, and a better understanding of the molecular odor space. Finally, we highlight the results of the expert-curated taxonomy by showcasing odor predictions for the case of pear odorants used in perfumery. Both taxonomies as well as a full molecular dataset are made available to the community, providing a stepping stone for a future community-driven exploration of the molecular basis of smell.

One of the key challenges to predict odor from molecular structure is unarguably our limited understanding of the odor space and the complexity of the underlying structure-odor relationships. Here, we show that the predictive performance of machine learning models for structure-based odor predictions can be improved using both, an expert and a data-driven odor taxonomy. The expert taxonomy is based on semantic and perceptual similarities, while the data-driven taxonomy is based on clustering co-occurrence patterns of odor descriptors directly from the prepared dataset. Both taxonomies improve the predictions of different machine learning models and outperform random groupings of descriptors that do not reflect existing relations between odor descriptors. We assess the quality of both taxonomies through their predictive performance across different odor classes and perform an in-depth error analysis highlighting the complexity of odor-structure relationships and identifying potential inconsistencies within the taxonomies by showcasing pear odorants used in perfumery. The data-driven taxonomy allows us to critically evaluate our expert taxonomy and better understand the molecular odor space. Both taxonomies as well as a full dataset are made available to the community, providing a stepping stone for a future community-driven exploration of the molecular basis of smell. In addition, we provide a detailed multi-layer expert taxonomy including a total of 777 different descriptors from the Pyrfume repository.

Since the 1990s, the term sensory turn has been used in the humanities to refer to the increased attention paid to the role and significance of sensory experiences in the analysis and interpretation of cultural phenomena. However, this term does not fully cover the concept, because researchers have long had a blind spot for the “lower” senses. Following Plato, Aristotle, Kant and Hegel, among others, this refers to smell, taste and touch. A similar development took place in art history. Whereas cultural history could already boast groundbreaking studies on smell in 1982, such as Alain Corbin's Le miasme et la jonquille (1982), there was still a gap in art history for a long time. Despite the fact that avant-garde artists made scents and tactile poems shine in their total works of art, art historians paid little attention to them. In recent years, this gap in art history seems to be closing. In this contribution, I will discuss a specific part of the “lower” sensory turn, namely the olfactory turn: the growing attention to the sense of smell, one of the last bastions to be conquered within the sensory turn.

Within the field of sensory museology, olfactory approaches are gaining more attention, from curators, heritage communication and education, artists and researchers. However, olfactory museology, conducting and studying experiments with smell in curatorial practices, is suffering from a lack of documentation - both regarding the experiments conducted, and the impact of the approaches. In this paper we report on the development of scented guided tours in the Rijksmuseum Amsterdam (2015-2020): a co-creation between academics, heritage professionals, and the scent industry. We describe 1) the creation of historically informed and artistic scents to accompany works of art, 2) the experimentation with different methods for olfactory storytelling and smell distribution techniques, 3) the development of a methodology for impact measurement (through questionnaires, interviews and observation), and 4) the outcomes of the impact analysis, also taking into account the advantages of olfactory storytelling for people of different abilities, in this case blind people and people with low vision.

The interrelationships between humans, smells and the built environment have been the focus of increasing numbers of research studies in the past ten years. This paper reviews these trends and identifies the challenges in smellscape research from three aspects: methodological approaches, artistic design interventions and museum practices, and odour policy making. In response to the gaps and challenges identified, three areas of future research have also been identified for this field: smell archives and databases, social justice within odour control and management, and research into advanced building materials.

For her doctoral dissertation “In Search of Lost Scents,” art and scent historian Caro Verbeek (Vrije Universiteit Amsterdam, Kunstmuseum, The Hague) collected olfactory neologisms or newly invented smell related words from (art) historical sources ranging from 1855 to 1975, which she categorised according to the themes poetry, mind, concepts, material and synaesthesia. Three never-before-published artistic illustrations by the author help establish a more embodied cognition of the meaning of some of these concepts, as including “smell images” is impossible. In addition, she has created a “synaesthetic odour wheel” based on literary sources (2021).

Unfortunately most of these events and objects are by now inodorate, lost, or never recorded. Therefore the (re)construction of these art historical scents, in collaboration with IFF (International Flavours & Fragrances) and several heritage institutions, such as the Rijksmuseum, will once again enable us to ‘get in touch’ with this volatile heritage. This research is financially supported by NWO.

No ‘visual’ artist addressed the sense of smell as often as Marcel Duchamp did. Whereas his solid objects can still be studied visually and textually, the scents he used have by now evaporated, and a vocabulary to describe them is lacking until today. What we have left are nose witness reports and the possibility to smell olfactory reconstructions. Rereading canonical text with a more sensory gaze and inhaling these historical fragrances, such as cedar, erotic perfumes and coffee, will enable us to reconstruct the olfactory dimension of our highly ocularcentric history of art.

When putting an olfactory reconstruction on display in a museum, curators, conservators, and scholars face many challenges. Three aspects should be taken into account: the perceived object (the replicated scent), the perceiving subject (associations and hedonic value then and now), and the physical and infrastructural circumstances (function and context then and now). Two examples will demonstrate the opportunities and risks professionals encounter when putting scents on display in an ocularcentric, deodorized institution. The first case study deals with ancient perfumes of which residual material was found in a perfume factory dating back to 2000 B.C. The second one deals with The Beanery: a multisensory artwork by Edward Kienholz in the collection of the Stedelijk Museum, Amsterdam.

Smell and taste are strong inducers of autobiographical and collective memories. Marcel Proust described a now famous taste memory almost a century ago. The main character in A la recherche du temps perdu suddenly gets transported back in time when tasting a madeleine cake dipped in lime tea. The flavor enables him to vividly relive moments long forgotten. According to Proust, consciously recalling an event by means of language or simply looking at the same object would not have had the same effect. What he understood intuitively is currently being explored by a growing number of artists and neuropsychologists. This article discusses two matters: (1) What are sense memories? (2) How are sense memories different from memories evoked by language? The analysis of works of art and scientific experiments with the closely linked senses of smell and taste demonstrate social, emotional, and aesthetic values. Finally, we reflect on the practical dimension of olfactory memory in society. Over the past decade interdisciplinary artists have increasingly been engaged in educational and care projects using the sense of smell. They appear to take a leading role in successfully applying the sense of olfaction in education and well-being.