Human odor profiles

The relationship between chemical structure and perceived odor has been studied by electrophysiological, chemical-analytical, and psychophysical techniques. Certain odorants in addition to being detected by the olfactory system evoke specific behavioral responses. Recent studies on various mammalian species have attempted to equate specific odor sources with behavioral patterns and to profile the odorants in hopes of Identifying the biologically active components ( ). In addition, studies on human odor suggest similarities in odor sources and types with other mammalian species and also suggest some of these odors may be reflective of internal body processes. 

Since man possess odor sources similar to mammalian species, it is of value to determine both the nature and the biochemical origin of these odorants. Profiling of human odors represents a non-invasive technique which might prove useful in the detection of many metabolic and Infectious disorders and for monitoring normal body processes. Alternatively, we may be unknowingly emitting and perceiving odorants which could effect our interpersonal relationships. Only further research in this area will determine to what extent this occurs. 

Madagascan Saro essential oil was found to have an attractive odor with a fresh eucalyptus type aroma, being the oil dominated by 1,8-cineole. The oil was found to be safe for human use, with low irritation levels, no mutagenicity and cytotoxicity. This EO also showed antimicrobial activity against several mold and bacteria. Due to its favorable organoleptic and chemical profiles, its safety and effective microbial activity, this oil may have application in the cosmetic, perfumeiy and pharmaceutical industries. The identification of new uses and application of essential oils, can ultimately assist rural communities in Madagascar by generating interest and market access to their products only if these new applications find a sustainable market. 

If I can ascertain what another organism detects via olfaction, then I can perform experiments upon it, which cannot be performed on human subjects. The objective of such experiments—to find out how odor is coded—has yet to be achieved. Suppose the olfactory code were unraveled. Reproducing an odor would become a matter of replicating the pattern of neural responses without having to duplicate the chemical stimulus (much as cinematography appears to reproduce color without necessarily matching the complete spectroscopic profile of the original scene) (Robertson, 1992). 

It has been observed that the discriminatory capabilities of human olfaction are tremendous It was estimated that an untrained person could differentiate up to ten million odors, perhaps even significantly more than that. Information theory then shows that in order to encode the qualities of ten million odors in a simple binary mode (Monoosmatic components on or off, their intensity, albeit important, is in this connection disregarded) only 2h to 27 specific profiles, disregarding possible and probable redundancies, and therefore the same number of complementary receptor sites would be required. Assuming furthermore that said redundancy, in which the informational modalities of two different specific receptor sites of two different olfactory neurons are confluent in one collector cell and therefore contribute to the expression of only one monoosmatic component is indeed operational it becomes necessary to increase the total number of types of specific receptor sites to 2k-30. This means that only 2U-30 specific detector proteins are required for structure recognition in the transduction process. This compares to about UOOO enzyme systems in different stages of activity estimated to be present in a cell any time. 

Odor intensity ievei (odor threshold number) n. A test to determine the intensity of an odorant, or the number of dilutions required for an odorant (gas, vapor, or hquid) in order to become odorless or barely detectable as evaluated by a panel of humans sniffing samples. Also the character of the odorant sample may be evaluated (e.g., sweet, sour, ethereal, and putrid) (ASTM D1292-86, Standard Test Methods for Odor in Water and ASTM Publication DS 61, Atlas of Odor Character Profiles). 

GC in combination with olfactometric techniques (GC-0) is a valuable method for the selection of aroma-active components from a complex mixture (7). Experiments based on human subjects sniffing GC effluents are described as GC-0. This technique helps to detect potent odorants, without knowing their chemical structures, which might be overlooked by the OAV concept (ratio of concentration to threshold) if the sensory aspect is not considered from the very beginning of the analysis. Experience shows that many key aroma compounds occur at very low concentrations their sensory relevance is due to low odor thresholds. Thus, the peak profile obtained by GC does not necessarily reflect the aroma profile of the food. 

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