In Pursuit of a Neroli Accord

After working with a broad range of natural scents to understand their nuances over a few years, only a few placed hooks deep in our brain.

The small sniff of a perfumer evaluating a scent—as an oenophile slurps instead of gulps—is quite distinct from the deep, rapturous inhale of a true believer. But in the deep gulp, the sustained inhalation, one can achieve a singing, ringing, bright joy in the brain that radiates outward beyond the body. This is one of the ways that scent can transport without tapping into scent-cued memory.

Neroli is one of those scents for us.

The name is beautiful; everything is in balance. It has the piney brightness, bitterness, and green woodiness from a wave of terpenes. It has the fruity, green floral notes of the best of rose and geranium. The indolic nature of the white flower is in full effect, but held at just the level so that it does not overwhelm. A hint of spice . . . what’s not to love?

Neroli is the essential oil distilled from the flowers of the Citrus aurantium (bitter orange) tree. Orange blossom absolute is the absolute extraction from the same flower, a much heavier, fatty, waxy, indolic scent closer to jasmine. Petitgrain refers to the essential oil distilled from the leaves and stems of the bitter orange tree, but can also come from other citrus trees.

With very little adornment, an excellent cologne could be just neroli essential oil in perfumers’ alcohol. This would be a cologne fit for royalty indeed, for a 150 ml perfume bottle at 10% would cost ~$200 just for the neroli; meaning a neroli-only cologne would cost 20-30x more than most colognes. It would also require frequent reapplication as the scent is somewhat fleeting.

In our attempts, a small percentage of neroli (even 15%) is not enough to shine through in a cologne composition designed to showcase neroli. Push just a bit too hard on the citrus aromachemicals (methyl pampelmousse (which we love!) or the natural valencene and a healthy dose of green mandarin and cedrat) and you end up with a citrus scent that pushes past the abbreviated heart to the base without stopping at neroli. Push on the aurantiol or methyl anthranilate or linalyl anthranilate or corps oranger and you will end up with a cloying, fruity mess.

After a dozen attempts at a neroli cologne, we decided it was time to make our own neroli accord.

The topic of neroli/orange blossom accords is perennial on the Basenotes DIY forum. There is frequent advice to check the accord for orange blossom on the Perfumer’s Apprentice site and advice to add indole to this as a suitable accord. This is for orange blossom and not neroli, but it is still too much aurantiol and oranger crystal.

The advice that got into our head was from Paul Kiler, who wrote, “It's not actually that hard to make a neroli base for yourself... It is one of the easier things (in the grand scheme of Perfumery) to try to challenge yourself, and accomplish as a learning perfumer.” He suggests looking up any number of GCMS results to build out the ingredients and proportions.

The one that has a hold on us is the Moroccan organic neroli essential oil from Eden Botanicals. This is 30% limonene, much higher than other oils, such as the 12% in the Egyptian variety also at Eden.

There are a number of problems with reconstitution based only on the GCMS. There are many trace materials that won’t drive the overall composition, but together provide the “natural” scent of the essential oil. In the Moroccan essential oil, the first 5 ingredients—Limonene (30%), Linalool (25%), beta-Pinene (15%), (E)-beta-Ocimene (10%), alpha-Terpineol (5%)—sum to 85% of the total weight. There are 16 compounds that each make up less than 0.5% of the total, all the way down to one that is only 0.02% of the total. We don’t have Ocimene in our organ or more than half of the trace compounds. It isn’t clear that the Ocimene we found online is the same form as the naturally-occurring compound.

We could copy the formula developed by Jamie Frater for $5, but that would defeat the purpose of learning how to do this.

We started with the following as an initial trial. The major ingredients are reduced to account for their inclusion in both the natural neroli oil and in the petitgrain heart essential oil.

Neroli Accord Experiment #1

Aldehyde C-9	0.5
Aldehyde C-10	1.5
Aldehyde C-11	1
beta-pinene	100
Orange Flower Ether	20
D-Limonene	225
Terpinolene	4
alpha terpineol	20
alpha-pinene	5
Petitgrain Heart	225
Linalool	164
Neroli	75
Linalyl Anthranilate	20
Nerol	20
Clary Sage Abs	5
Oranger Crystals	5
Indole	4
Nerolione	5
Geranyl Acetate	30
Geroniol	10
aurantiol	10
benzyl salicylate	25
Farnesol	10
caryophyllene	5
corps oranger	10
Total	1000