How Rose Absolute Is Made

Rose is the most-cited example of why natural materials cost what they do, and the numbers hold up to scrutiny.

The harvest window

Rosa damascena in Bulgaria and Turkey, and Rosa centifolia in Morocco and France, flower for roughly three to four weeks. Within that, flowers must be picked before dawn: volatile content falls measurably as the sun rises, and by mid-morning a meaningful proportion is gone.

The entire year's production is therefore determined by a few weeks of intensive hand labour, at a time of day that makes mechanisation impractical.

Concrete, then absolute

1. 01Flowers are washed with hexane, dissolving aromatic compounds along with waxes and pigments.
2. 02The solvent is evaporated under vacuum, leaving a waxy concrete.
3. 03The concrete is washed with warm ethanol, which dissolves the aromatics but not most of the wax.
4. 04The solution is chilled to precipitate remaining waxes, then filtered.
5. 05The ethanol is evaporated under vacuum, leaving the absolute.

The yield figures

Commonly cited industry figures put rose concrete yield at roughly 0.2 to 0.25 percent of flower weight, with absolute at roughly half the concrete. Rose otto, produced by distillation instead, is generally quoted at around 0.03 percent — three to four tonnes of flower per kilogram of oil.

Why absolute and otto differ

Phenylethyl alcohol is a major contributor to the smell of a living rose. It is also appreciably water-soluble, so in steam distillation much of it partitions into the distillation water rather than the oil. Solvent extraction has no such loss.

That single fact accounts for most of the difference: absolute is rounder, sweeter and closer to the fresh flower, while otto is more transparent and crystalline, with a cool top note absolute lacks.