What are the methods and extractions of Rose oil?

Answer 1

There are three main methods: distillation, solvent extraction, and carbon dioxide extraction.

In distillation, roses and water are placed in a still, where the mixture is heated until the water vaporizes; the rose oil is released into the water and also vaporize. The vaporized water and rose oil are collected and condensed. The water is drained back off and distilled again to obtain parts of the oil that dissolve in water. The combined oil is called "attar of roses." This method is quite ancient, but the use of heat changes the scent, making it dissimilar from that of fresh flowers.

In solvent extraction, the roses are mixed with a solvent that dissolves the aromatic compounds as well as pigments and wax. The solvent is vacuumed up for re-use, leaving behind a waxy substance. This mass is mixed with alcohol, which dissolves only the aromatic compounds. The alcohol is then evaporated to secure the rose oil. This method preserves a greater portion of the substance of the flower and does not subject the oil to heat, so it is considered to be a more faithful rendering of the scent. This product is called "rose absolute."

In carbon dioxide extraction, liquid CO2 at high pressure is used to dissolve out the aromatics. When the pressure is released, the CO2 immediately evaporates, leaving the rose oil behind. It's a very efficient process that faithfully preserves the scent of the flowers, but the equipment is expensive. This product can also be called an absolute, or sometimes "CO2 extract."