Aroma compound

Odorants or odorants include all natural and synthetic fabrics that develop an odor if they are perceived olfactory. Here, the odor is not a property of the substance, but is given to him only by smelling. The term fragrance is often used interchangeably, but this is limited to fragrances which are produced by plants or animals and used their communication, for example as pheromones.

In order to be perceived as an odor can a substance in the medium of air must be distributed, be volatile. Volatile odorants are distributed quickly, flooding rapidly, low-volatility develop a lower vapor pressure; issued in ventilated rooms, volatile therefore disappear sooner. Whether a vaporized fuel quantity is to smell, but not only depends on their concentration in the air volume from, but much of whether it is above the threshold odor. The odor thresholds can be very different for different odorants and each is determined by the olfactory function of the perceiver. The lower the odor threshold for an odorant, the less concentrated it can be smelled; and the less, this increased threshold during the exposure, the longer lasting this concentration can lead to an odor impression.

Most fragrances are molecules below a certain molecular size (or molecular mass, MR < 300) and consist of a polar fraction, for example, a functional group and a nonpolar component, such as a hydrocarbon backbone. Since the proteins of olfactory receptors are chiral, mirror-image enantiomers of a fragrance can cause a different smell under certain circumstances. For triggering an odor apparently essential functional groups are called Osmophore. Odorants are raw materials in the perfume production.

The sales on the world market in 2006 increased for all substances that were used as odors or flavors ( perfumes and flavorings), around 18 billion U.S. dollars.


Examples of aroma chemicals

  • Anethole
  • Benzaldehyde
  • Benzyl alcohol
  • Citronellal
  • Citronellol
  • Coumarin
  • Decanal
  • Ethyl acetate
  • Ethyl butanoate
  • Ethylvanillin
  • Eugenol
  • Geraniol
  • Heliotropine
  • Indole
  • Isoamyl
  • Ionone
  • Limonene
  • Menthol
  • Vanillin