…what do roses smell of?
Some roses smell honeyed, some smell green; some even smell like peaches and cream. Oops, I made a rhyme! I suppose I’m in the spirit of Valentine’s Day after I was treated to a lovely bouquet of velvety-red flower shop roses which smell strongly of… phenylethyl acetate. I did what anyone would upon receiving such a gift – buried my nose in and inhaled deeply.
At first I thought I still had some phenylethyl acetate stuck up my nose from work (I had been working on a hyacinth accord, which is built around other materials but to which I had added a bit of phenylethyl acetate for its honeyed-green ‘flower shop’ note).
Roses are incredibly varied, not just in appearance, but in scent, too. One of the Lush founders once brought in a peach-coloured rose bud from her garden which smelled very strongly of lemons, and asked me to replicate the scent for her. I made an accord she was so happy with she exclaimed: “It smells better than the real thing!” Needless to say I was delighted she was so pleased, and it made me curious about roses as a garden plant – I am not an expert gardener and hadn’t really explored the types of roses available. Since then I’ve pinned dozens of roses from David Austin Roses and other suppliers, and look forward to seeing which ones I might manage not to kill…
The rose used in perfumery is commonly Rosa damascena which I’ve been lucky enough to smell in the field as the rose pickers deftly pluck whole blooms before sunrise. The petals are gathered in large burlap sacks and taken to the distillery where they’re spread in a large room before processing.
A good rose picker can gather fourty kilos of petals a day and it takes four tonnes of roses to produce just one kilo of rose oil, and one tonne to produce a kilo of rose absolute. These figures are direct quotes from the source, and I have seen the process in action – it’s mind-boggling to see what a sea of roses it takes to fill just one small container with rose oil.
Rose oil is the distillation product, with water-soluble parts left in the distillation water (which is sold as rose water). After distilling twice, a white-yellowish, waxy liquid with a heady, honeyed scent is left; precious and potent, so luckily not much of it is needed in a blend for it to have an effect.
Rose absolute is produced by washing the petals with hexane – a complex process which demands several rounds of washing and rinsing. First, a rose concrete is made, which contains everything you can possibly extract from the petals, including the wax. Rose concrete is stored ‘as is’ sometimes, for later processing (it’s better preserved that way). Once the concrete is washed, you’re left with rose wax and rose absolute. Since the yield is so much better with rose absolute production, this material is several magnitudes less costly than rose oil (rose otto). Rose absolute captures the scent of the rose most accurately, though smelling the blooms on the field, the impression was different again; strong geraniol impression in the morning dew. Roses have to be picked as early in the morning as possible to stop the sun’s rays evaporating too much precious oil. The pickers have to work fast and choose the open blooms.
If garden roses are of interest, perhaps a visit to the David Austin gardens at Albrighton might be in order – they have 2 acre gardens with over 700 different rose varieties! I’m definitely going to go there before choosing which roses I’ll plant in my garden.
Rose chemistry is fascinating – there are over 300 chemicals in rose oil, some of which are still unknown to science. While it’s really easy to make a rose-like smell from a handful of basic constituents (phenylethyl alcohol, geraniol, citral, rose oxide…), the real oil and absolute add such complexity that nothing comes close. On the other hand, if one were to aim for an accord which replicates the scent of roses in bloom, first you’d have to pick which rose (the lemony ones? Ones which have a hint of banana? Perhaps the ones that smell like wine?) – and then add creative touches to the rose accord to achieve the desired effect.
Compound Interest publishes fun chemistry posters every week and this time they’ve been looking at flowers:
I adore what they’re doing (I did write an article about how everything is made of chemicals, and how the whole division of ‘synthetic vs. natural’ is peculiar when looking at safety – aesthetics aside, the origin of a chemical has nothing to do with safety).
I hope your Valentine’s Day is fragrant and if any of you have rose gardening tips, do let me know…