3. Natural Fragrant Raw Materials

The determination of the most important olfactory contributors of a fragrant natural raw material can be an extremely long and complex task which requires the combination of very efficient analytical techniques. Indeed, the characterization of these components is often difficult since the global odor of complex mixtures is not only due to the sum of the olfactory properties of each constituent, but also involves many synergies between each odorant constituents. In addition, the main contributors are often strongly potent odorants contained only in trace amounts, and therefore, their identification requires an exhaustive analysis of the whole mixture. Finally, since the olfactory sense is characterized by strong interindividual differences, a large number of panelists must be involved in such studies in order to bring generalizable data. Consequently, there is still lack of accurate knowledge about the main odoriferous constituents for many natural raw materials, and this situation is paradoxical when it concerns materials widely used for their odorant properties in the flavor and fragrance industry.

This chapter presents an overview of the published data about the main odor-active constituents of a selection of natural fragrant raw materials. It describes the chemical structures and olfactory properties of the main odorant components reported in the literature for 10 extracts and essential oils, after a brief description of the general analytical and sensorial issues concerning the determination of key odorants in a mixture.