A Gardener’s Pride and Joy

Although this article arrives rather late, I have had it in mind to write about my lilies of the valley since the beginning of May when they were in bloom. During that time, bunches of these white porcelain bells could also be found wrapped in their green leaves and sold as bouquets. But since I much prefer the process of growing and coaxing a plant into blooms, especially one whose fragrance I have yet to smell in situ, I had planted their rootstocks or ‘pips’ in autumn last year. They lay dormant over the winter and only began to send out their leaves in mid-March when the weather warmed. A littler later, some flower stalks emerged, and I could enjoy the redolence of spring.

muguet pips

Pips emerging from dormancy in spring. The carpet of seedlings around the pips are violets, which also emerge from the seeds of last year.

The perennial lily of the valley or muguet (Convallaria majalis) returns every year to perfume the spring air. But despite its delicate-looking white bells, muguet is highly poisonous and, especially without blooms, often dangerously mistaken for the edible herb bear leek (Allium ursinum). Nonetheless, grow a small patch in a dedicated pot of its own for an olfactory pleasure and all the caution can be thrown in the wind.

Its ethereal scent smells fresh, obviously floral, even spicy, and with a watery green tone. I would describe it as a mix of rose, clove, jasmine, green saps, and musky sweetness. But in spite of these contrastingly opulent notes, the overall character of muguet is reserved, and it feels like a subtle and an elegant way of announcing spring. Lily of the valley, as such, has been a prime objective of perfumers who have tried to capture its mesmerising scent and, along with it, the allure of spring.

Lily of The Valley in Perfumery

Just as elusive as it is captivating, lily of the valley virtually refuses to be extracted. Steam distillation does not yield a desirable quality of essential oil and solvent extraction with either petroleum ether or butane, though sufficient to produce the concrete for research, gives too low a yield to be commercially tenable. Perfumers must therefore rely on their memory and headspace analysis of the natural scent to reconstitute and interpret lily of the valley with existing essential oils and aroma ingredients.

The first of such aroma chemicals were the aldehydes (-CHO), such as hydroxycitronellal, Lilial, and Lyral. These are some of the most well-known muguet odorants of this family. Hydroxycitronellal was the prototype; it encompasses all the facets of lily of the valley — despite itself not being naturally occurring. It had been discovered and marketed by Knoll & Co. in 1905, but soon various qualities from other manufacturers were available, such as Laurine (1906) and Cyclosia (1908). The next stage of muguet was, then, dominated by Lilial and Lyral, starting from the 1960s. They would eventually come to supplant hydroxycitronellal.

These muguet aldehydes found their use directly in a composition or alternatively in a compounded base. Hydroxycitronellal, for instance, first found its fame with the aldehydic floral perfume Quelques Fleurs (Houbigant, 1912). It had also been used to compound Lily 7 — a base comprising seven ingredients — which was employed in the composition of Arpège (Lanvin, 1927), another successful aldehydic floral perfume. Other classic perfumes such as Chanel N°5 (1921), Ma Griffe (Carven, 1946), L’Air du Temps (Nina Ricci, 1948), and Youth Dew (Estée Lauder, 1952) likewise benefited from this lily of the valley odorant. But hydroxycitronellal was just as popular in the enduring fragrance of Nivea Cream, which has notes of muguet, ylang ylang, rose, geranium, violet (ionones) as well as cinnamic and balsamic ones.

Later perfumes, however, relied more on the newly available odorants when they were first created. For example, Fidji (Guy Laroche, 1966) employed Lyral, imparting thus a green tone to its floral bouquet. Similarly, Calandre (Paco Rabanne, 1969) used Lyral in addition to hydroxycitronellal to give a green emphasis that accentuates its character of metallic rose. Even more so, the elaborate floral accord of Anaïs Anaïs (Cacharel, 1978) was based on hydroxycitronellal, Lilial, Lyral, and Cyclamen aldehyde. Interestingly, compositions such as Aromatics Elixir (Clinique, 1971), Coriandre (Jean Couturier, 1973), and Paloma Picasso (1984) used a combination of the muguet aldehydes partly for their floral notes that contrast beautifully with patchouli.

Interestingly, such muguet aldehydes was also used in the formation of Schiff bases. When an amine (-NH2) reacts with an aldehyde (-CHO), a Schiff base and water are formed. For example, methyl anthranilate reacts with hydroxycitronellal and Lyral to form Aurantiol and Lyrantiol, respectively. The Schiff bases produced can give odours of orange blossom, linden blossom, or tuberose. Perfumes such as Oscar (Oscar de la Renta, 1977), Poison (Dior, 1985), and Lou Lou (Cacharel, 1987) derived much of their sweet floral character in such a manner at the time.

Even in the last few years, the classic muguet aldehydes, such as hydroxycitronellal, Lilial, and Lyral could still be found. In adr_ett (Nomenclature, 2015), the lily of the valley, which lends a green floral touch to the fruity musk, was based on the combination of hydroxycitronellal and Lilial. And, as much as 12% Lyral was used in Inflorescence (Byredo, 2013) to build its lily of the valley character. Indeed, these muguet aldehydes have proved to be one of the enduring ingredients of perfumery.

But that is about to change.

Due to their skin-sensitising potential, these muguet aldehydes are facing restrictions. Hydroxycitronellal is allowed only up to certain concentrations depending on the end use, but Lilial and Lyral are severely restricted. According to the Scientific Committee on Consumer Safety (SCCS), Lilial is considered ‘not safe for use as fragrance ingredient in cosmetic leave-on and rise-off type products’ even at the concentrations set by the International Fragrance Association (IFRA), and Lyral ‘should not be used in consumer products’.

New odorants are therefore being developed to replace these restricted ones. Amongst them, the aldehydes  account for a broad range of muguet odour profiles that includes names like Dupical, Florhydral, Melafleur, Floral Super, Cyclemax, et cetera. There are also the alcohols (-OH), such as Mayol/Meijiff, Florol/Florosa, Mugetanol, Majantol, Lilyflore, Muguesia, and Super Muguet, and these are a sought-after class of muguet odorants because of their non-sensitising nature. Super Muguet, for instance, was first used in contrasting the fig accord of Marc Jacobs Men (2002), and it was later used in the oriental-gourmand Noir Pour Femme (Tom Ford, 2015). Amongst recently debuted ingredients, I had the chance to smell Mahonial, which offers a diffusive, creamy lily of the valley note reminiscent of the yellow blooms of Mahonia japonica, from whose name it is derived. Mahonial was first employed in the floral heart of Missoni (2015), and now one can smell its transparent yet creamy note in L’Homme (Prada, 2016) and La Femme (Prada, 2016), both containing Mahonial at approximately 4% and 2%, respectively.

As reflected in the many examples of perfumes, the muguet note is a part and parcel of many different styles of fragrances. It follows then that the quest for safe, stable, and impactful lily of the valley aroma chemicals must continue.

Lily of The Valley in Perfumes

The fresh watery appeal and creamy sensuality of muguet lend a special touch to a composition. For this reason, it is not limited to soliflore perfumes, and forms an important part in many styles of compositions.

But, of course, if one wishes to know how perfumers interpret lily of the valley, exploring soliflore perfumes is a good option. There have been several other muguet soliflores since the eighteenth century, from Lily of The Valley (Floris, 1750), Premier Mai (Houbigant, 1908), Muguet de Chaville (Cheramy, 1910), Muguet des Bois (Coty, 1941), Muguet du Bonheur (Caron, 1952), and Muguet de Guerlain (1998 by Jean-Paul Guerlain), to name a few. But I would rather offer a few favourite choices of this flower.

Naturally, one of these is the most well-known and appreciated lily of the valley: Diorissimo (1956). Considered to be the gold standard, its fresh green floral and surreptitious animalic notes conjure the vernal impression of damp woodlands covered in infinite patches of lily of the valley. In the current eau de toilette, its muguet has lost some radiance and its woodlands short on their animalic richness, but I think that its curious paradox of an ethereal flower with a veiled depth still rings true.

However, the lily of the valley that I find most captivating is far from the time-tested repertoire of classics. Muguet Porcelaine (Hermès, 2016), I feel, takes after the spirit of Diorissimo in simplicity and subtle depths, but its singular focus is where it diverges. Whereas Diorissimo is an impressionistic rendering of blooms in their woodlands, Muguet Porcelaine is a careful treatise dedicated solely to muguet, examining its accents and shades. Led by fresh accents of rose and clove, its green floral is not only depicted in detail, but also underpinned by watery melon and green sap that remain fresh until the dry down.

Other than the soliflores, the lily of the valley note, as evident in the examples heretofore, finds itself in various genres. Indispensable to the bouquet of the aldehydic florals, lily of the valley is a part of perfumes such as Chanel N°5, Arpège, Madame Rochas (1960), Calandre, Rive Gauche (Yves Saint Laurent, 1971), and White Linen (Estée Lauder, 1978). It is also found in the multiplex bouquets of L’Air du Temps, Fidji, and Anaïs Anaïs. Beyond these floral bouquets, it finds contrast and harmony in many interesting accords. In perfumes such as Aromatics Elixir, Coriandre, and Paloma Picasso, the lily of the valley accentuates the floral complex that is set against the patchouli and woods. This contrast between muguet and patchouli is also employed in the mellis accord of oriental perfumes such as Opium (Yves Saint Laurent, 1971) and Coco (Chanel, 1984). But the lily of the valley also shines brightly with green notes, where its green floral character finds harmony. In Chamade (Guerlain, 1969), a hint of muguet bridges between the green galbanum and hyacinth opening and the floral heart. This bridge between green galbanum and floral heart is similarly found in Chanel N°19 (1970). As the green notes are making a come-back, so too is the lily of the valley note, and this is seen in the green, dewy floral introduction of Miu Miu (2015).

But ultimately the perfume that has a special place in my memory of May is that of the lilies of the valley which I had coaxed into bloom. They were my pride and joy.

Sources: M. Meunier, Ind. Perfum., 5, 26, 1950; Naves and Mazuyer, Les Parfums Naturels, Paris (1939), p 250; Scent and Chemistry The Molecular World of Odors p 13, 108; SCCS Opinion on HICC SCCP/1456/11 revised 27 July 2012; SCCS Opinion on BMHCA SCCS/1540/14 revised 16 March 2016.

*Lilial is a tradename for butylphenyl methylproprional (BMHCA).

*Lyral is a tradename for hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC).

Part 3: Neroli oil and orange blossom absolute

This is the third and final part of the series ‘The bitter orange tree: bigarade, petitgrain, orange leaf, neroli, and orange blossom’.

If rose is the queen and jasmine the king, then bitter orange flower is the princess of all flowers. The youthful, radiant, and romantic scent of these vernal blossoms captures the spring time. The main extracts of bitter orange (Citrus aurantium subspecies amara) flower are neroli oil and orange blossom absolute.

orange blossoms.jpg

Legend has it that neroli oil is named after the princess of Nerola, Marie-Anne de la Trémoille, who was known to have perfumed her gloves and bath with the essential oil of bitter orange flowers. Neroli oil has a fresh floral profile with green and spicy tone that recalls petitgrain oil. But despite their olfactory resemblance, the contents of ocimenes, β-pinene, limonene, linalool, and linalyl acetate of neroli oil are higher than those of petitgrain oil. Moreover, neroli oil also possesses the jasmine odorant cis-jasmone as well as the exotic jasmine note of 1H-indole and the Concord grape of methyl N-methylanthranilate that differentiate it from petitgrain oil. And interestingly, despite coming from a citrus plant, nootkatone and other typical components of citrus oils are not found in neroli oil.

Production of neroli oil and orange blossom absolute concentrates in Tunisia, Morocco, and Egypt in April. It starts from manual picking. The flowers are picked by hand to avoid damaging the immature flower buds, which will be collected in subsequent harvests. After distillation, around 850 kg to 1000 kg of flowers yields 1 kg of neroli oil. The Tunisian oil has the fresh floral note of orange flower and is reminiscent of freshly ironed linen. The Moroccan variety possesses the fresh floral sweetness of orange flower, but also harbours green and animalic aspects.

To obtain orange blossom absolute, around 1000 kg of flowers are loaded into an extractor with a solvent for heating. The solvent is later removed by evaporation, leaving the liquid ‘concrete’ of orange blossom, which solidifies at room temperature due to the presence of wax in the flowers. The collected concrete is melted down and mixed with alcohol at 60°C. After an hour of mixing, it is cooled down to 0°C to remove the solidified wax from the mixture. Finally, the alcohol is removed by evaporation to yield roughly 1 kg of orange blossom absolute. Tunisian orange blossom absolute is floral, warm, sensual, and heady — typical of orange flower. The Moroccan origin is also warm, but more animalic and indolic. Moreover, the by-product of steam-distilled flowers can be solvent-extracted to produce orange blossom water absolute, which has a harsher orange blossom character, is less indolic, and not as heady when compared to the absolute.

There are several aspects that impart distinguishing features to neroli oil and orange blossom absolute. The hydrocarbons such as α-pinene, β-pinene, myrcene, limonene, and ocimene confer the bright citrus note. Particularly important are the ocimenes, which provide a very fresh citrus note with a subtle green accent. These compounds make up about 40% of neroli oil whose sparkling and diffusive character is used to add freshness to a composition. In contrast, the hydrocarbons constitute only around 6% in the absolute that is, nonetheless, employed to boost the floralcy of other components.

Meanwhile, the alcohols are a class that contributes to the floral notes. These include linalool, phenyl ethyl alcohol, α-terpineol, citronellol, nerol, geraniol, nerolidol, and farnesol. Amongst these, linalool provides much of the character impact.

As for the esters found in extracts of bitter orange flower, they serve as accents to modify the citrus notes. Such esters are linalyl acetate, methyl anthranilate, neryl acetate, citronellyl acetate, and geranyl acetate. Methyl anthranilate, also a nitrogenous compound, is the most important of its kind and can be found up to 10% in the absolute; its fruity and floral character is essential to both neroli oil and orange blossom absolute.

Yet, another minor but important class of compounds is phenol. Eugenol is an important phenol in extracts of bitter orange flower. Despite being a minor constituent, its spicy clove note imparts a kind of brightness and natural character to the flower.

Interestingly, important nitrogenous compounds found in extracts of bitter orange flower are the aforementioned methyl anthranilate, indole which is a potent floral chemical with animalic character, and pyrazines that impart green, dry, and earthy character. The high-impact 2-isobutyl-3-methoxypyrazine, for example, confers a green facet that recalls galbanum oil and green peppers to neroli oil. The pyrazines are, perhaps, what give orange blossom extracts their peculiarity that can add a long-lasting, signature freshness to the top note.

Neroli and Orange Blossom in Perfumery

Such insights into the chemical compositions of bitter orange flower are also essential to the reconstitution of an orange blossom or neroli note. This is because extracts from bitter orange flower are very expensive and, in most cases, can only be afforded in small amounts.

A classic reconstitution of the orange blossom note, for instance, is through a Schiff base formed by a reaction between an aldehyde (–CHO) and an amine (–NH2) such as methyl anthranilate. One of the most widely used Schiff bases in the reproduction of orange blossom and neroli notes is Aurantiol, which is produced by the reaction between hydroxycitronellal and methyl anthranilate. The only problem with Schiff bases is that they are strongly yellow and would pose a problem, should discolouration be a concern. In any case, they can be further used in compounding orange blossom or neroli notes in bases or fragrance composition itself.

New odorants for orange blossom or neroli notes have also been developed and could lend special signature to such fragrance bases, and hence fragrance compositions. Nerolione® is an example of a high-impact, very stable, non-discolouring orange blossom material. Even in small amounts, it performs excellently in challenging bases of household and personal care products. But it can also be used in fine fragrances to brilliant effects. Perfumer Maurice Roucel dosed a few parts of Nerolione in Insolence (Guerlain, 2006) and brought out the floral radiance of violet. It may not provide a scent of its own in a formula, but it creates a synergy with floral and fruity notes, giving a blooming effect.

Neroli and Orange Blossom in Perfumes

In terms of use, neroli oil most famously finds itself in eaux de cologne. In the past, we would find around 7% neroli oil in 4711 Echt Kölnisch Wasser (Mülhens, 1792) or even 5% neroli oil in the revived Green Water (Jacques Fath, 2015) in contrast to the 0.5% neroli oil that lends just a bright dandy touch in Habit Rouge (Guerlain, 1965). An example of a ground-breaking composition in the eau de cologne style that employs neroli is Eau Sauvage (Dior, 1966).

Moreover, we also find orange flowers in compositions of other styles such as lavender water, aldehydic, chypre, and amber types. These include Chanel N°5 (1921), Arpège (Lanvin, 1927), Fleurs de Tabac (Cherigan, 1929), Vol de Nuit (Guerlain, 1933), Fleurs de Rocaille (Caron, 1934), Miss Dior (1947), English Leather (1949), and Fidji (Guy Laroche, 1966). Another interesting example is the development of a jasminic facet of neroli oil in 24 Faubourg (Hermès, 1995). The sensual floral character of orange blossom is key to masterpieces such as Après L’Ondée (Guerlain, 1906) and L’Heure Bleue (Guerlain, 1912).

Sources: P&F Vol.6 June/July 1981 by Felix Buccellato, P&F Vol.16 November/December 1991 by Mans H Boelens and Antonio Oporto, P&F Vol.9 February/March 1995 by Danute Pajaujis Anonis, P&F Vol.34 March 2009 by Jeb Gleason-Allured, Scent and Chemistry The Molecular World of Odors, west-crete.com