All official volatile oils are of vegetable origin. All official volatile oils are of vegetable origin



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All official volatile oils are of vegetable origin.

  • All official volatile oils are of vegetable origin.

  • Normally pre-exist in the plant – stored in a special secretory tissue (e.g. Citrus peel oil cells or oil ducts in umbelliferous fruits).

  • EXCEPTION: Oil of bitter almond – formed by hydrolysis of the glycosides.



Therapeutically (Oil of Eucalyptus)

  • Therapeutically (Oil of Eucalyptus)

  • Flavouring (Oil of Lemon)

  • Perfumery (Oil of Rose)

  • Starting materials to synthesize other compounds (Oil of Turpentine)

  • Anti-septic – due to high phenols (Oil of Thyme). Also as a preservative (oils interfere with bacterial respiration)

  • Anti-spasmodic (Ginger, Lemon balm, Rosemary, Peppermint, Chamomile, Fennel, Caraway)

  • Aromatherapy



Volatile oils are products which are generally complex in composition, consisting of the volatile principles contained in plants, and are more or less modified during the preparation process.

  • Volatile oils are products which are generally complex in composition, consisting of the volatile principles contained in plants, and are more or less modified during the preparation process.

  • Only 2 procedures may be used to prepare official oils

  • Steam distillation

  • Expression

  • 4 Main types of volatile oils

  • Concretes

  • Pomades

  • Resinoids

  • Absolutes



Prepared from raw materials of vegetable origin (bark, flowers, leafs, roots etc.)

  • Prepared from raw materials of vegetable origin (bark, flowers, leafs, roots etc.)

  • Extracted by HC type solvents, rather than distillation or expression – Becomes necessary when the essential oil is adversely affected by hot water or steam (e.g. jasmine).

  • Produces a more true-to-nature fragrance.



Concretes contain about 50 % wax and 50 % essential oil (jasmine).

  • Concretes contain about 50 % wax and 50 % essential oil (jasmine).

  • Ylang ylang (concrete volatile) contains 80 % essential oil and 20 % wax.

  • Advantages of concretes: they are more stable and concentrated than pure essential oils.



True pomades are (volatile oil) products of a process known as enfleurage (hot or cold).

  • True pomades are (volatile oil) products of a process known as enfleurage (hot or cold).

  • Enfleurage is used for obtaining aromatic materials from flowers containing volatile oils to produce perfume long after they were cut.



A glass plate is covered with a thin coating of especially prepared and odourless fat (called a chassis).

  • A glass plate is covered with a thin coating of especially prepared and odourless fat (called a chassis).

  • The freshly cut flowers are individually laid on to the fat which in time becomes saturated with their essential oils. The flowers are renewed with fresh material.

  • Eventually the fragrance-saturated fat, known as pomade, may be treated with alcohol to extract the oil from the fat.



Prepared from natural resinous material (dried material) by extraction with a non-aqueous solvent, e.g. Petroleum ether or hexane.

  • Prepared from natural resinous material (dried material) by extraction with a non-aqueous solvent, e.g. Petroleum ether or hexane.

  • E.g. Balsams – Peru balsam or benzoin; resins (amber or mastic); Oleoresin (copaiba balsam and turpentine); Oleogum resins (frankincense and myrrh)



Can be viscous liquids, semi-solid or solid.

  • Can be viscous liquids, semi-solid or solid.

  • Usually homogeneous mass of non-crystalline character.

  • Uses: in perfumery as fixatives to prolong the effect of a fragrance.



Obtained from a concrete, pomade, or a resinoid by alcoholic extraction.

  • Obtained from a concrete, pomade, or a resinoid by alcoholic extraction.

  • The extraction process may be repeated.

  • The ethanol solution is cooled & filtered to eliminate waxes.

  • The ethanol is then removed by distillation.

  • They are usually highly concentrated viscous liquids.





In most cases, the biological function of the terpenoids of essential oils remains obscure – it is thought that they play an ecological role – protection from predators & attraction of pollinators.

  • In most cases, the biological function of the terpenoids of essential oils remains obscure – it is thought that they play an ecological role – protection from predators & attraction of pollinators.



Synthesis & accumulation of essential oils are generally associated with the presence of specialized histological structures, often located on or near the surface of the plant:

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