This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American
If you’ve been near a garden lately, chances are your nose has picked up on the unmistakable scent of the roses in full-bloom in many places right now. The sight of the rose certainly holds a great amount of symbolic meaning in cultures throughout the world, though it can be argued that smell is even more important. According to an article on the "attar" or fragrant oils of the rose in the May 1921 Scientific American Supplement, “Supreme among the charms of the rose is its exquisite and haunting fragrance, a fragrance at once delicate and powerful…Small wonder that the ancients felt the perfume to be the soul of the rose…”
When the article was written, the majority of rose essence was made in the Balkans where the high amount of crumbled syenite made the soil very fertile. Both red roses (Rosa Damascena) and white roses (Rosa Alba) were planted, although the red’s fragrance was much stronger. If a garden were properly planted, it would yield about 100 pounds of flowers per day for 3 weeks. The flowers had to be gathered before the sun was too high in the sky, as the buds needed to remain unopened. Then, the flowers had to be taken to a nearby distillery as quickly as possible, as the oil’s fragrance is weakened after 24 hours.
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Inside the distilleries, stills that consisted of copper alembics 3 to 5 feet high were arranged in rows and rested atop a furnace built of bricks. Each still held about 22 pounds of flowers (both petals and stem) and 20 gallons of water. The mixture would be heated and drawn up through a condenser tube, which was surrounded by cold water. This was done until 10 liters of rose water had been acquired. The still was then opened and the flowers removed, while the remaining hot water was returned and mixed with cold water to make 20 gallons of water that would be mixed with fresh flowers. The process ran until about 10 gallons on rose water had been collected.
From this 10 gallons of distilled rose water, a little over a tenth was collected and put into a flask while the rest was returned to the distilling process. Within the flask, the oil gradually rose into the neck of the flask and was skimmed off with a small funnel. In Bulgaria, 3000 kilos of rose leaves yielded 1 kilo of attar.
In France, only the petals of the rose were used. Steam stills would be used in order to protect the flowers from being burned, creating purer and stronger smelling rose oil. Attar of rose differs depending on the locale where the plants were grown as well as changes in climatic conditions.
Some distilleries tried to cut the rose oil with other attars from geranium or ginger-grass and lemon, which devalued the pure essence. To prevent this, many larger buyers of rose oil hired confidential investigators to drop in on distilleries and make sure their processes were not corrupt.
While the article offers several wonderful images of the rose fields and the distillation process, it’s a shame they were not printed in color, or as scratch-n-sniff for that matter.