Once you become interested in perfumes, you begin to search for answers to hitherto unknown mysteries, such as trying to learn what aldehydes really smell like. (A few years ago, before I had registered on my first perfume forum, I don’t think I had ever heard the word “aldehyde.”) The perfume neophyte soon realizes that aldehydes are everywhere in perfumery, although they do not seem to be terribly popular these days. Bad perfumes are often dismissed in reviews because they are “too aldehydic.” Aldehydic notes are called “screechy” and their scent is compared to nail polish remover and hair spray. But if you continue to read and explore the world of perfumes, especially vintage perfumes, you soon realize that aldehydes are getting a bad rap.
A little basic research reveals that aldehydes comprise a large and diverse category of molecules and they do not all smell the same. Given all the talk of “screechy aldehydes,” it is surprising to learn that vanillin is an aldehyde, along with cinnamaldehyde, the dominant natural compound in cinnamon. And then there is the merry confusion generated by the misnaming of gamma-undecalactone, a perfume ingredient discovered in 1908, as the aldehyde C-14. This so-called aldehyde, really a lactone, may be the most important and delightful “aldehyde” of all, having been used by Jacques Guerlain in 1919 to add plush fruitiness to the chypre structure to create Mitsouko and by Edmond Roudnitska in 1944 to compose the even more sensual, musky Femme.
After clearing your mind of all misapprehensions regarding aldehydes (…hairspray? peaches?), you can get down to the business of trying to understand aldehydes in themselves and without prejudice. For me, the penny dropped when I took my first sniff of vintage Chanel No. 5 extrait from a 1950’s flacon. As everyone knows, in 1921 Ernest Beaux used unprecedented quantities of the recently discovered, but largely untested aldehydes to create a perfume that was defined by its clean and unapologetic artificiality. Of these specific aldehydes, Patricia de Nicolaï, perfumer and perfume historian, writes:
Aldehydes became first available in 1903 when Darzens synthesized aldehyde C-12 MNA (/methyl nonyl acetaldehyde, first used in Quelques Fleurs), and Blaise prepared the series of aliphatic aldehydes: C-8, C-9, C-10 (10), C-110 (11), and C-12 which remained unexploited for years. Their odor can be described as being waxy, metallic, or the burnt smell of a snuffed candle. (1144)
My vintage No. 5 extrait immediately made me think of wax, not the smell but the texture or, more precisely, the mouthfeel. Vintage No. 5 gives me the feeling that I am chewing off a thick layer of old fashioned lipstick, one scented with rose, ylang ylang, and jasmine. As I wear No. 5, this initial impact of the aldehydes softens, but the waxy smoothness of the scent lingers into the drydown.
If No. 5 gave me my first clear perception of what aldehydes can do for perfumes, then No. 22 is an even more convincing demonstration of the beauty and power of aldehydes. Launched just a year after No. 5, No. 22 has been part of the Chanel perfume range and sold alongside No. 5 ever since. Today, the company describes No. 22 as “a light variation of No. 5” that lets “tuberose blossom forth.” Perhaps the current version does. Meanwhile, the No. 22 that I know, an EDT earlier than the 2007 Les Exclusif version but not especially old, has very little connection to No. 5. My No. 22 combines potent aldehydes with frankincense and sandalwood, with jasmine, lily of the valley, and not whiff of tuberose to my nose. The aldehydes in No. 22 feel opaque, waxy, hard, like the rosin used for ballet shoes, a dark, dry, sticky resin that increases friction.
Andy Tauer loves vintage perfumes, and I find that he rethinks traditional perfume ingredients in ways that make them appeal to contemporary taste while keeping a clear connection to their traditions. In 2013, Tauer launched Noontide Petals, a modern, not especially floral aldehyde that feels like a beautiful, but extremely somber homage to No. 22. Noontide Petals opens with the tang of bergamot. Its white petals, which I perceive as mostly jasmine and ylang ylang, are heavily coated with the waxiness of the aldehydes. It may be noon, but the “snuffed candle” scent of the aldehydes and their dry resinous quality mingles with the smoky frankincense and patchouli notes to suggest the interior of a dark chapel, dimly lit by votive candles.
de Nicolaï, P. (2008), “A Smelling Trip into the Past: The Influence of Synthetic Materials on the History of Perfumery.” Chemistry & Biodiversity, 5: 1137–1146.