Olfaction perception

Schiffman, S.S., Pearce, T.C. Introduction to olfaction perception, anatomy, physiology, and molecular biology. In Pearce, T.C., Schiffman, S.S., Nagle, H.T., Gardner, J.W. (eds.) Handbook of Machine Olfaction Electronic Nose Technology, pp. 1-32. Wiley-VCH, Weinheim (2003)... 

Multiple senses, including taste, contribute to our total perception of food. Our perception of the flavor of food is a complex experience based upon multiple senses taste per se, which includes sweet, sour, salty and bitter olfaction, which includes aromas touch, also termed mouth feel , that is, texture and fat content and thermoreception and nociception caused by pungent spices and irritants. Taste proper is commonly divided into four categories of primary stimuli sweet, sour, salty and bitter. One other primary taste quality, termed umami (the taste of L-glutamate), is still somewhat controversial. Mixtures of these primaries can mimic the tastes of more complex foods. 

Gower, D. B., Ruparelia, B. A. (1993) Olfaction in humans with special reference to odorous 16-androstenes Their occurrence, perception and possible social, psychological and sexual impact. J. Endocrinol. 137, 167-187. 

Olfaction, research in, 18 383-384 Olfactory membrane, 11 567 Olfactory perceptions, 11 510-511 Olfactory receptors, 18 383-384 Olfactory response, 11 566-567 01igo(2-propenyloxy)methyloxyirane, sulfonation of, 23 720 Oligocyclic lattice host inclusion compounds, 14 177-179 Oligocyclic lattice hosts, 14 177 01igo(y-caprolactone)dimethylacrylate, in shape- memory polymer networks, 22 364... 

Beyond that, the sense of olfaction does not depend on the concentration of the odorant concentration invariance. If you are exposed to jasmine at very low concentration, it smells like jasmine if the concentration is significantly raised, it still smells like jasmine. Perhaps more to the point is the concentration invariance of complex aromas such as that of coffee. The brain forms a single perception from complex inputs, regardless of the intensity of the signal. Olfaction has this property in common with taste. 

Here is a bit of a complication there is a lot of individual variation in the sense of human olfaction. Not everything smells the same to everyone. This holds both for the intensity of the perceived smeU as well as for its quality pleasant, floral, skunky, sweaty, or no odor at all. Andreas Keller has recently demonstrated that some significant part of this individual variation in the sense of smell derives from genetic variation in human odorant genes. Specifically, two single nucleotide polymorphisms (SNPs), leading to two amino acid substitutions in an odorant receptor, have dramatic affects on the perception of the odor of androstenone, a steroid derived from testosterone. 

The gravitational field affects olfaction as it does vision, audition, or vestibular function. It could impair detection of dangerous fumes or burning electrical equipment in airplanes or space vehicles. Astronauts also report altered perception of food flavors under weightless conditions. Men and women tested with four scratch-and-sniff odor samples of the University of Pennsylvania Smell Identification Test identified odors more poorly when in an upside-down position (Mester eta/., 1988). 

Human perception of flavor occurs from the combined sensory responses elicited by the proteins, lipids, carbohydrates, and Maillard reaction products in the food. Proteins Chapters 6, 10, 11, 12) and their constituents and sugars Chapter 12) are the primary effects of taste, whereas the lipids Chapters 5, 9) and Maillard products Chapter 4) effect primarily the sense of smell (olfaction). Therefore, when studying a particular food or when designing a new food, it is important to understand the structure-activity relationship of all the variables in the food. To this end, several powerful multivariate statistical techniques have been developed such as factor analysis Chapter 6) and partial least squares regression analysis Chapter 7), to relate a set of independent or "causative" variables to a set of dependent or "effect" variables. Statistical results obtained via these methods are valuable, since they will permit the food... 

Perceptions related to Annoyance, intensity, Olfaction Odors ... 

Siddiqi O. (1991) Olfaction in Drosophila. In Chemical SensesNol. 3, Genetics of perception and communications, eds C. J. Wysocki and M. R. Kare, pp. 79-96. Marcel Dekker, New York. 

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