Costus Absolute

#### Costus Absolute. **Costus **extracts have been manufactured on a smaller scale in France and a few other countries for several decades. The raw material is the Costus root, see description under **Costus**** ****Oil**** **Substantial quantities of the root are still exported from the Himalayan areas to perfume houses all over the world for distillation or extraction. The **Costus**** **root contains certain very high boiling aromatic materials. Accordingly it requires a lengthy distillation which is harmful in general to most constituents of essential oils. Extraction with hydrocarbon solvents (benzene or petroleum ether) at modest temperature will produce a concrète of a rich and true-to-nature odor. An absolute is produced from the concrète by the conventional alcohol extraction method. The **Concrète**** **is commercially called **Costus Resinoid**. The costus root which has been steam distilled for essential oil is occasionally extracted with a volatile solvent. This second extraction yields a resinous and faintly aromatic material which unfortunately is used as a "cutting" agent for true **Costus Resinoid**. Other so-called **Costus**** ****"Resins" **are merely residues from the rectification of costus oil. An **Anhydrol **of **Costus **is commercially available. It is a molecular distillate of costus root extract. A neutral solvent is co-distilled with the extract. **Costus Absolute **is a semi-solid mass or very viscous liquid of pale amber or brownish-amber color. Its odor is similar to that of the essential oil but it appears at first much weaker and less harsh The odor of the absolute is strikingly similar to that of the root itself—to those who have had the opportunity of smelling the root material. The odor of the absolute is soft, sweet-woody and fatty without any unpleasant "harsh" or "rancid- fatty" notes. The tenacity of this odor is tremendous and its fixative value can hardly be overestimated. **Costus Absolute **is available at a quite attractive cost thanks to the fact that the yield of alcohol- soluble absolute by extraction of the concrète (or "resinoid") from costus root is almost the same as the yield of essential oil by steam distillation. However, only an increased demand will bring the price of the absolute down near the cost-level of the essential oil. The trend in perfumery raw material production is steadily going toward the extracted products rather than the distilled ones. This is particularly true when the problem is "expensive" perfume materials. Several Grasse factories specialize in extracting practically any natural raw material to produce a perfume material. **Costus**** ****Absolute**** **and **Costus**** ****Concrète**** **(costus "resinoid") are used in similar perfume combinations as those described under **Costus Oil**.