Concrete, in perfumery, is a semi-solid mass obtained by solvent extraction of fresh plant material.
Contents
Production
Fresh plant material is extracted with nonpolar solvents (e. g., benzene, toluene, hexane, petroleum ether). On evaporation of the solvent, a semi-solid residue of essential oils, waxes, resins and other lipophilic (oil-soluble) plant chemicals remains.
Uses
Because of the heavier nonvolatile compounds (waxes, resins), concretes are only partially soluble in ethanol. Therefore, they are of limited use in perfumery, but they can be employed for scenting soaps.
The concrete may be extracted with ethanol to produce an absolute.
References
Concrete (perfumery) Wikipedia(Text) CC BY-SA