June 6, 2006

This year’s annual meeting of the Association for Chemoreception Sciences (AChemS) featured more events and papers of interest to the fragrance industry than usual. The meeting, which is held in April in Sarasota, Florida, draws most of its contributors and attendees from academic ranks. This tends to give the meeting a focus that is not of immediate interest to people from our industry. Over the past year, however, a newly energized Industrial Relations Committee has greatly increased corporate memberships and has used the corporate membership dues to fund a symposium presented at this meeting entitled: Taste and Smell in Translation: Applications from Basic Research. The symposium speakers reviewed the current, hot areas in smell and taste molecular biology and perception in a way that was understandable to the non-expert. They also suggested some potential product applications for this new technology. The industry people at the meeting gave the symposium a big thumbs-up!

The committee also worked with Theresa Molnar, Executive Director of the Sense of Smell Institute, to develop the Science of Fragrance Award. The award recognizes an outstanding slide or poster presentation on research that has relevancy for application to the creation and/or marketing of fragrance products. This year’s winner was Dr. John Prescott of the James Cook University, Carins, Queensland, Australia. His poster is reviewed below.

This meeting is the largest one devoted solely to taste and smell. A mix of 500 posters and slide presentations are presented to the around 800 participants. It is a very intellectually stimulating – and exhausting event. I have attended the majority of the 28 annual meetings and have always come away with my batteries recharged, and during my 23 years at IFF, with a number of new product ideas. Of the 503 posters and papers presented at the meeting, I have culled out seven which are presented below. It could have just as easily been 27. After reading through my seven reviews you may be inspired to check out the full list of papers presented this year on the AChemS website at: http://www.achems.org/clientuploads/FinalCompleteShortProgram.pdf

The poster and slide presentation abstracts will be published in the October 2006 issue of Chemical Senses.

Presentation Highlights
1) Sweet Odors Increase Pain Tolerance. This paper won the Science of Fragrance Award given by the Sense of Smell Institute. Shortly, the authors will be submitting a white paper that reviews this area. This paper will be put up on the SOSI website. Jenell Wilkie and John Prescott found that sweet odors increase a subject’s tolerance to pain induced by cold. What I find interesting is not that sweet odors may some day become an aspirin substitute but that the analgesic effect of smelling a sweet odor is hypothesized to be caused by secretion of endorphins in the brain. Wilkie and Prescott tell us, however, that the endorphin release is not due intrinsically to the sweet smell of the odorant but to its paired association to a sweet food. As most of us know endorphins interact with opium receptors in the brain to reduce the perception of pain and to make us feel good. Endorphin release may very well be the hidden reward of smelling a sweet odor and the reason why sweet smelling fragrances and aroma chemicals are so commercially successful. In fact, I doubt if there is a commercially successful fragrance that does not contain a sweet note.

2) Molecular Structure Predicts Human Judgments of Pleasantness and Similarity. Noam Sobel’s group at U.C. Berkley found a way to correlate the molecular structure of an odor with its perceived pleasantness. Up to this point people in the field have tried mainly to correlate molecular structure with odor character. Consistent aroma chemical odor character information is difficult to generate, with the possible exception of musk aroma chemicals, which have a very characteristic odor. Pleasantness and intensity, on the other hand, are the two key attributes that underlie the odor character of a aroma chemical. Dr. Khan in Sobel’s lab used Andy Dravnieks’s data set of 160 odors characterized by 146 attributes. Principle component analysis (a statistical technique) of these data showed the first attribute to be pleasantness. That is, people were subconsciously basing their selection of odor attributes on their preference for the odor. To compare the molecule’s pleasantness to its molecular properties Khan used a computer program called “Dragon” (http://www.talete.mi.it/main_exp.htm ) which supplied 1500 molecular properties for each of the molecules in Dravnieks’ data set. Turning the crank, Khan found that fewer than 20 molecular properties predicted the pleasantness of the molecules. They then used these molecular properties to predict the pleasantness of molecules outside the data set. It will be interesting to see if the molecular structures that correlate with pleasantness correlate with some other odor attribute such as sweetness or a mood attribute such as confidence.

3) The Inhibition of Stress – Odor Conditioning. This work is out of Dr. Pamela Dalton’s lab at the Monell Chemical Senses Center. Dr. Dalton’s group used galbanum, an odorant that smells like a freshly broken green twig, as the odorant. This odorant is well known to perfumers and people associated with the fragrance industry, but it is a novel odor to people outside the industry. The use of a novel odorant is to avoid prior odor associations that can interfere with the experimentally induced ones. Subjects were exposed to galbanum during a stressful task (public speaking) or during a non-stressful task (watching a pleasant slide show). Upon re-exposure to galbanum subjects exhibited either stress or relaxation responses depending on their prior conditioning. This is an example of the paired association of an odor with a negative or positive emotion and it verifies this phenomenon scientifically. Fragrance marketing has employed paired associations for years. Fragrances are associated with emotional moments and beautiful people. Dr. Dalton’s work shows that people subconsciously feel the effect of the association when re-exposed to the fragrance.

4) Heterosexual Females but not Lesbians Sensitize to Low Levels of Odorant. This study was carried out by Dr. Charles Wysocki and co-workers at the Monell Chemical Senses Center. Here’s the background. Dr. Pam Dalton, a colleague of Dr. Wysocki’s at Monell, reported that woman not men developed increased sensitivity to an odorant when re-exposed to it over a series of sessions. Specifically, the concentration at which the women could first detect the odor (detection threshold) decreased with repeated exposure. Wysocki asked what happens if a lesbian is exposed to the same odor over a series of sessions, will she become more sensitive to it or will her sensitivity remain unchanged? He found that their sensitivity to the odorant remained unchanged, which is the same response that men show. Dr. Wysocki does not have an explanation as yet for his findings. This leaves the readers of this paragraph free to come to their own conclusions.

5) Different Cerebral Activation Produced by a Putative Social Chemosignal and Perceptually Similar Odorants. This title is not inviting to someone outside the field of olfactory neurophysiology. We’ll attempt to translate it to lay terms for our readers. Androstadienone has been shown previously by Dr. Charles Wysocki’s group at the Monell Chemical Senses Center and Dr. Martha McClintock’s group at the University of Chicago to be a human pheromone. Androstenone, the boar pheromone and a molecule in the same molecular class (steroid) as androstadienone, does not exhibit pheromone properties in humans. Does androstadienone activate a different part of the brain than androstenone? This was the question asked by the six researchers whose labs at the Universities of Dresden (Germany), Basel (Switzerland) and Berkeley (California) contributed this paper. They found, using fMRI brain scans, that in fact androstadienone produces different patterns of activation in the brain than does androstenone. This is an interesting result because it brings up the question of whether macrocyclic musks are special. For example, do muscone, exaltone, ambrettolide, or muskalactone produce a brain activation pattern that is similar to androstadienone? This question is prompted by the observation more than 20 years ago that these macrocyclic musks can assume the same molecular geometry as steroids such as androstadienone and androstenone. (A macrocyclic musk is a molecule that has a large ring composed of 15 or 16 carbon atoms, a macro ring, as the main element of its structure. This ring is very flexible and can bend in such a way as to assume the geometry of a steroid.) The techniques developed for this study can now determine whether this group of musks in fact exhibit human pheromone properties.

6) The Influence of Smelling Coffee on Olfactory Habituation. Here is another contribution of Noam Sobel’s lab at U.C. Berkeley. This one should be near to the hearts of perfume evaluators and sales people. Smelling coffee aroma is thought to clear the nose after smelling a perfume so as to increase its sensitivity for the next evaluation. Coffee aroma is not the only odor used for clearing the nose. Other popular nose clearing techniques employ smelling a swatch of wool or smelling an unfragranced forearm. Noam’s group did the study and found that smelling coffee aroma between perfume samples, as compared to smelling unscented air actually works. The perceived odor intensity of the perfume from sample to sample stayed the same after smelling coffee aroma while it decreased when smelling air between samples. The pleasantness of the perfume, however, was similar after smelling coffee or air. This is the first scientific evidence that coffee aroma works.

7) Floral Odor Prompts Positive Emotion Searches. This poster was the work of Dr. Pat Wilson of La Salle College, in Philadelphia and Drs. Coffield and Jeannette Haviland-Jones of Rutgers University in New Jersey. Haviland-Jones and Wilson recently provided a Paper entitled Fragrance: Emotion, Sensuality and Relationships; which can be found on the Sense of Smell website. In their paper they hypothesize that:

“Fragrance can be a biological “search engine.” If the fragrance of happiness is in the air, even if we do not “know” the scent of happy, we will search for happy events and people.”

In previous work they found that a gift of a bouquet of flowers increased the amount of happy smiles (Duchenne smile) and social behavior and decreased negative mood reports. In this work they ask the question: will floral odors also affect emotional behavior, will it serve as a biological search engine? Using peppermint, gardenia and solvent (ethyl alcohol) as their test odorants, the researchers found that floral odors do indeed prompt positive emotion searches. This result takes us back to the first paragraph, the work of Wilkie and Prescott who found that sweet aromas which are subconsciously associated with sweet foods increase the secretion of endorphins in the brain. Is the same mechanism at work for floral odors, i.e., a paired association to flowers? Flowers, however, unlike sweets do not provide an energy reward. So why do people spontaneous like flowers? We do not know. The effect of flowers on people is special. Haviland-Jones and Wilson, in their SOSI sponsored paper tell us that flower delivery people are often hugged and kissed by the recipient of the flowers. This is a case of the messenger not getting shot.

References:
1. SWEET ODOURS INCREASE PAIN TOLERANCE, Wilkie J.1, Prescott J.2; 1School of Psychology, James Cook University, Cairns, Queensland, Australia; 2Psychology, James Cook University, Cairns, Queensland, Australia

2. MOLECULAR STRUCTURE PREDICTS HUMAN JUDGMENTS OF PLEASANTNESS AND SIMILARITY, Khan R.M.1, Luk C.2, Flinker A.3, SobelN.1; 1Neuroscience, University of California, Berkeley, CA; 2Bioengineering, University of California, Berkeley, CA; 3University of California, Berkeley, CA

3. THE INHIBITION OF STRESS – ODOR CONDITIONING, Maute C.1, Sitvarin L.1, Petrova M.1, Dalton P.1; 1Monell Chemical Senses Center, Philadelphia, PA

4. HETEROSEXUAL FEMALES, BUT NOT LESBIANS, SENSITIZE TO LOW LEVELS OF ODORANT, Wysocki C.1, Sergeant M.2, Louie J.1 1Monell Chemical Senses Center, Philadelphia, PA; 2Division of Psychology, Nottingham Trent University, Nottingham, United Kingdom

5. DIFFERENT CEREBRAL ACTIVATION PRODUCED BY A PUTATIVE SOCIAL CHEMOSIGNAL AND PERCEPTUALLY SIMILAR ODORANTS, Gerber J.C.1, BensafiM.2, Husner A.3, Frasnelli J.4, Reden J.4, Hummel T.4; 1University of Dresden, Dresden, Germany; 2Neuroscience, University of California, Berkeley, Berkeley, CA; 3ENT Department, University of Basel, Basel, Switzerland; 4ENT, University of Dresden, Dresden, Germany

6. THE INFLUENCE OF SMELLING COFFEE ON OLFACTORY HABITUATION, Secundo L.1, Sobel N.1; 1Neuroscience, University of California, Berkeley, Berkeley, CA

7. FLORAL ODOR PROMPTS POSITIVE EMOTIONAL SEARCHES, Wilson P.1, Coffield C.2, Haviland-Jones J.2 1Psychology, La Salle University, Philadelphia, PA; 2Psychology, Rutgers, The State University of New Jersey, Piscataway, NJ