Vanilla: the universal ingredient

Prosecco upgraded with Vanilla Cognac
Pell Wall style

Vanilla is one of the most useful ingredients in cooking, cocktails and perfumery.  Its story is quite well known, so I’m only going to touch on some of the less well-known aspects here.  My main purpose is to give details of a fine drink and a tincture that are easy to make at home.

So, first up, the drink: once upon a time, when I had more money and less sense I conducted a research project into the Champagne Cocktail - a hedonist’s research project rather than an academic one - I tried variations on the Champagne cocktail in every bar I could find that served one to try out the differences.  Much was learned and more was drunk ... including me from time to time.

Vanilla Cognac

Filtering the cognac
(while drinking coffee)

One of the things I discovered was a variation called the Vanilla Classic - sadly now both the bar where I found it and the key ingredient are gone.  That ingredient was Navan - a fantastic vanilla Cognac made by the same people who produce Grand Marnier.

So why am I telling you about a drink you can’t buy? Well, it inspired me to have a go at my own and I’d like to share the process with you:

Take one bottle of good (XO ideally) supermarket cognac and put in two pods of Ugandan Vanilla - leave it where you'll remember to shake it now and then for about four months.  Take out the pods, filter the cognac but reserve the pods (you’ll see why in a bit).

Almost done

Your Cognac should now be a beautiful mahogany colour and filled with complex vanilla flavours as well as all the richness of the fine brandy itself.  You can drink it just as it is, add sugar to make something that more closely resembles Navan but I think it works fantastically used to upgrade a glass of Prosecco - which has enough sweetness of its own to sustain the extra alcohol - drink and enjoy!

Vanilla Tincture

Don’t waste the beans after you’ve
made the vanilla cognac

Now back to those pods: it seems a shame to let them go to waste and one of the lesser-known facts about vanilla is that in perfumery the absolute (see this post for a definition of absolutes and other extracts) is normally used but it isn’t easy to work with, so for the small-scale perfumer a tincture is an alternative.

Here’s my technique for a tincture that’s a bit out of the ordinary:

Let the pods from your cognac-making dry out then chop them up, along with another fresh pod or two, weigh them all together and put the whole lot into nine times the weight of perfumers alcohol (so as to create a 10% Tincture), adding a shot or two of the cognac to the blend (I used about 50g).  Just as with the cognac, wait for at least four months shaking whenever you think of it but at least every few days.

Result: vanilla cognac you can drink plus a vanilla tincture that you can use in perfume making at about 7 times the quantity you would the pure absolute.  The cognac in the tincture gives it an extra complexity and also encourages more flavour out of the pods due to the water content - unlike many materials vanilla tinctures better in a lower strength alcohol 

Resist the temptation to drink the tincture though ...

Tolu Balsam

Tolu Balsam is a very useful natural fixative as well as a lovely base-note in its own right, but it isn’t the easiest of materials to handle.  It comes from the South American tree Myroxylon balsamum.  

It is used to fix materials such as juniper, petitgrain, spices and florals of many kinds and frequently forms a key component of oriental and chypre styles of perfume.

Rock-likc pure Tolu Balsam

Arctander describes it as: "a brown, orange-brown or dark yellowish brown mass, brittle when cold, and the fracture is glasslike or flintlike. Its odor is sweet-balsamic, cinnamic in type, faintly floral and with an undertone of vanillin.” and at normal UK temperatures it’s certainly rock-hard and behaves rather like a chunk of Brighton Rock when it’s broken.

Tolu and TEC form a strange, alien landscape

So to make it practical to handle it needs to be diluted in a suitable solvent - it’s often sold already diluted in this way though the dilution isn’t always declared nor the solvent named - I bought a pure Kg recently and diluted it ready for use in TEC (tri-ethyl citrate) in a process that turned out to be both quite involved and to produce some fun images, so I thought I’d write it up here.

Is that a creature emerging?

The first job was to get the Kg of rock-like Tolu Balsam soft enough to pour out of its container, which I did by sitting the container in a bain-marie and boiling the water beneath it: this took a few hours before the material was fully liquid.  Meanwhile a pre-weighed out amount of TEC was heated on my heater-stirrer with a stirring bar already in the bottom of it (if you don’t heat the solvent as well the tolu will go hard again as soon as it hits the cool liquid and takes much longer to go into solution).

The next step is to pour the hot, liquid tolu into the pre-warmed solvent (insulated gloves are called for for this step of course).  At this point we realised that there was a photo opportunity as the resulting non-yet-mixture looked like an alien landscape.  The tolu settled to the bottom of the solvent and the application of glass rods was necessary to get it to start dissolving as it was much too sticky for the automatic stirrer at that stage: as those went in it started to look like one of those scenes from the Alien series where the creatures start unfolding from the cave walls . . .

  This is all being done in a three litre glass beaker and as you can see in the later pictures the manual stirring took some time before we could leave the automatic stirrer to get on with the job on its own and the balsam tended to dry on the glass very quickly too.

The cling film you can see was to minimise loss of aromatic quality as this was all being done hot, although with such a high-boiling material and high-boiling solvent that isn’t a big concern.

A stirring start

Gloopy-looking stuff

Pasta possibly?

Eventually it reached the stage where it was liquid enough for the automatic stirrer to do its stuff and with the stirrer on a low setting it was left overnight to complete the mixing, kept at a constant 60 degrees centigrade by the integral heater.  By morning it was fully mixed to form a dark brown, consistent, mobile liquid and here you can see me concentrating hard as I pour it into a (slightly pre-warmed) 3Kg glass reagent bottle. The bottle is on the scale so that I can check the amount that’s gone into it for stock control purposes.

Perfect for Perfume: Tolu Balsam at 30% in TEC

We even captured a little video of that part of the process, which gives you a clear idea of the consistency once it’s finished:

A few chips and flakes were left over from the mixing process and these were put into a plastic jar  - the picture at the top of this post is of those, a few weeks later by which time they have merged together to form a single solid but uneven lump, much like that with which the whole process started.

Lily of the Valley – mystery, manufacture & murder

Mystery

Perfumery has always glorified the floral and for centuries perfumers have sought ways to extract the essence from real flowers to incorporate into their creations. With many flowers this quest has met with considerable success, with a few commercially viable products produced that are still used in modern perfumery: rose and jasmine being the primary examples. 

Lily of the Valley - picture courtesy of Wikimedia Commons

One flower that has always eluded extraction is the Lily of the Valley (Convallaria majalis) or Muguet*: distillation yields very little of an unpleasant smelling oil not a bit like the dense, exotic scent of the fresh flowers.  Solvent extraction and even modern CO2 extracts have similarly been completely unable to capture the scent.  This is because the flower produces the scent only at the point of release – none is stored in the flower – so it cannot be extracted.  The flower itself only contains pre-cursor chemicals from which the scent is formed directly into the air.

Diorrissimo - picture from Basenotes

Yet many people will be familiar with the scent of Lily of the Valley, not through smelling the fresh flowers, but from perfumes containing or replicating its scent – perhaps the most famous of these being Diorissimo.  So, if you can’t extract the scent, how is that done?

---

*Muguet is the French word for Lily of the Valley, a flower popularly used at weddings.  Lily of the valley is a  sweetly scented (and highly poisonous) woodland flowering plant that is native throughout the cool temperate Northern Hemisphere in Asia, Europe and in the southern Appalachian Mountains in the United States.

Manufacture

Here we see how the chemist is the perfumers best friend: a good number of materials have been discovered or created that replicate, at least in part, the scent of these mysterious flowers.  Many people would say that synthetic Lily of the Valley begins with the synthesis in the early part of the 20^th Century of Hydroxycitronellal: it’s difficult to be sure exactly when it was first used because the nature of the material was kept a closely guarded secret.  What we do know is that as early as 1906 it was being made by Givaudan and sold under the trade name Laurine. 

Dr E Emmet Reid
Credited with re-discovering Hydroxycitronellal
Image from The Johns Hopkins University

At the outbreak of WWI it was being manufactured in Germany and, as the war meant it ceased to be available, efforts were made to find ways to make it that resulted in it’s being manufactured in an American factory and, during the 20s, it gradually become well-known within the trade.  Most perfumers would agree that, while no one chemical can ever fully represent the scent of a flower, hydroxycitronellal gives a very close facsimile to the aroma of the fresh flowers of Lily of the Valley.  Curiously enough however it does not appear to be present in that, or any other natural flower scent.

I’m presenting in the sections at the end of this post, descriptions of a selection of materials that replicate the scent of Lilly of the Valley, with descriptions of their olfactory properties as well as, in many cases, the restrictions on their use that have led to their decline.  These are mainly for the benefit of DIY perfumers, but may also be of interest to perfumistas curious about ingredients.  I’ve included quite a few quotations from Steffen Arctander’s wonderful descriptions of aroma chemicals – rather less well known than his work on materials of natural origin – but just as good.

Murder

Structure of Lyral - image courtesy Wikimedia Commons

So where does the murder come in?  Well in one case a forthcoming ban by the European Union will, over the next couple of years, result in the certain demise from perfumery altogether of one of those materials.  The material that is being killed off by the regulators is Lyral and although it’s only going to be banned in the EU, that will very likely be reflected in a prohibition by IFRA (the International Fragrance Association) and even if it isn’t all the major perfume manufacturers will phase it out of use completely, so it will effectively vanish from the world.

After the jump you can read detailed descriptions of a range of materials used in connection with Lily of the Valley scents.

Natural Perfume Materials: what the terms mean

There are quite a few methods by which the aromatic principles of natural materials are made available for use in perfumery and unfortunately some of the terms used are obscure and others are sometimes mis-used.

The purpose of this post is to set out the main terms used, together with definitions of widespread acceptance.  In putting these together I have relied on two main sources: first Arctander’s Pefume and FlavorMaterials of Natural Origin – written in the 1950s and early 60s but still regarded by most perfumers as the definitive work.

Second Brian Lawrence who is published regularly in Perfumer & Flavorist Magazine and elsewhere and is, probably, the definitive modern writer on the subject.

Before we get into the terms for natural materials, it is perhaps useful to examine what we mean by natural in this context and eliminate terms used to indicate synthetic materials.  Very few materials are suitable for use in perfumery exactly as they occur in nature: citrus oils and copaiba balsam are the main exceptions, requiring no processing beyond pressing the peel or releasing the balsam from the tree: in the great majority of cases processing is necessary and in some cases the odorous principles only form during processing (see my post on Bitter Almond Oil for an example of this).  A material is generally considered to be ‘natural’ when that processing is primarily physical, rather than chemical, in nature: these things are what this post is about.

Fragrance Oils are not usually natural

The term Fragrance Oil is widely used to indicate a blend of materials that may be both natural and synthetic, designed to replicate a natural odour.  These are often composed entirely from synthetic ingredients and almost never with entirely natural ones and as such do not fall within the definition of a natural material.  Occasionally they may be passed off as natural, sometimes innocently by traders who have themselves been deceived by a producer, but for the most part they are sold labelled as ‘fragrance oil’ and are usually cheaper than natural equivalents where these exist.

The main types of volatile isolates that are obtained commercially are essential oils, concretes, absolutes, pommades, resinoids, spice/herb oleoresins, extracts, infusions, and tinctures. The definitions of these, and some other important terms are set out here and for convenience I’ve started by listing first the three most common types – Essential Oil, Concrète and Absolute.  All other types follow in alphabetical order for ease of reference.

The most common natural materials

Bergamot in cultivation
(courtesy Wikimedia)

Essential Oil: The isolated aromatic portion of a plant that is borne in that plant within distinctive oil cells. In some exceptional cases the essential oil is formed during processing. Most essential oils are isolated by either hydro-distillation (water, steam or both) or cold pressing with some few being produced by dry (including destructive) distillation.  Water distillation implies direct contact between the plant material and the boiling water, steam distillation implies steam being produced separately and blown through the material – in the combined case the water is heated by injected steam.  Some essential oils are routinely ‘rectified’ after production – a process that may be entirely physical or may involve the introduction of synthetic aroma chemicals to standardise the odour.  Examples include Bergamot, which is routinely rectified to remove bergaptens (furocoumarins) – this is done by fractional distillation.  White Thyme is natural thyme oil that has been corrected by the addition of aroma chemicals to produce standardised oil chemistry – for most this would no longer be considered a natural product.

Concrète (often written as concrete with the same meaning):  an extract of fresh (cellular) plant material made using a hydrocarbon solvent, commonly hexane or petroleum ether. It is rich in hydrocarbon soluble material and devoid of water-soluble components. It is generally a waxy semi-solid, dark colour material free from the original solvent used in extraction, often containing a high percentage of largely odourless plant waxes.

Orris root being dried

One important note here on misuse of this term concerning Orris Butter, which is frequently called Orris Concrète, but is more correctly the essential oil of orris (the roots of certain species of Iris), which happens to be solid.  There is also a true Orris Concrète, from which a true Orris Absolute is made – the latter is a clear, mobile liquid unlike the so-called Orris Concrète or Butter which is solid at room temperature.

Absolute:  A highly concentrated alcoholic extract, usually of a concrète, which contains only alcohol soluble materials. Its primary use is in alcoholic perfumes but normally contains little or no residual ethanol.  Absolutes are also sometimes extracted from pommades (sometimes called Absolute from Pommade or Absolute from Châssis - the latter term is sometimes used to describe an absolute made by extracting the spent flowers already used in enfleurage).  An Absolute from Distilation Water (e.g. Rose Water Absolute) is also sometimes made using the hydrolat left over from making an essential oil as the starting material.  Sometimes the term Absolute is also used to mean the alcohol soluble fraction of a resinoid.

Other terms in alphabetical sequence

Copaifera langsdorfii 

Balsam: A natural exudate obtained from a shrub or a tree (either physiological or pathological). It is characterized by being rich in benzoic and cinnamic acids and their corresponding esters and is insoluble in water but completely or almost completely soluble in ethanol.  Balsams may, upon ageing, form resins and so the boundary between these two may be blurred.

CO² Extract – these include a range of extraction processes using carbon dioxide as the solvent.  In most cases the solvent used is rendered liquid at much higher temperatures than normal an so the extract produced is often, more correctly, referred to as SFE – supercritical fluid extract – and I’ve said a bit more about it under that heading.

Extract: A concentrate of a dried less volatile aromatic plant part obtained by solvent extraction with a polar solvent.  In practice this term is used quite indiscriminately to mean several of the types of processed material where there result is concentrated – with the solvent removed.  In flavour work the term is used even more widely to include emulsions and diluted materials that may be water soluble (possibly dissolved in water) and of very short shelf-life. To be meaningful this term really requires further qualification or clarification and perfumers should approach ‘extracts’ with appropriate caution.

Note that the French term ‘extrait’ (directly translated this would be extract) is used in English to mean something quite specific: An alcoholic extract of a pomade produced by enfleurage: a tincture of a pomade.   The term is also occasionally hijacked to mean an alcoholic dilution of any material of a particular strength or a blended perfume of a particular strength “extrait strength” is sometimes used to mean much the same as Parfum, that is an alcoholic perfume with 15-30% aromatic ingredients.

Gum: Can be either a natural or synthetic material but, strictly, should be used only for water-soluble materials of very high molecular weight.  In perfumery it can, however, also be used of resins and turpentines.  Under the strict definition gums are odourless and therefore of no use in perfumery.

Commiphora myrrha tree one of the primary sources
from which the oleo-gum-resin
myrrh is harvested.

Gum Resin: A natural exudate obtained from a tree or plant. It is comprised of gums and resins. If the gum resin source also contains an essential oil, it is called an oleo-gum-resin.  Only partially soluble in alcohol, hydrocarbons etc. and may be partially soluble in water where the proportion of gum is significant.

Infusion: A hot extraction of either a plant part or its exudate with either water or an organic solvent. Infusions are not at all popular because it is difficult to control their chemical composition.

Isolate: sometimes clarified as natural isolate, this is prepared material, produced from a precursor of natural origin, most often an essential oil, by any of a range of physical processes including fractional distillation or freezing, chromatographic separation and others.  At one time many perfumery materials were made this way that today are available much more cheaply as synthetics.  Natural perfumers may still take advantage of the fact that many natural isolates continue to be produced commercially for the flavour industry where the premium on natural flavours justifies the increased cost of production.

Oleoresin: The natural tree trunk or bark exudate, which is extremely rich in an essential oil.  The term is occasionally also used of prepared materials.  In either case they consist of essential oil and resin.  Turpentines are oleoresins where the resin portion is acidic.

Pommade:  The product of the enfleurage fat extraction of fresh flowers. Enfleurage was once much more widely used than today but is still the most efficient (highest yielding) method with certain flowers that continue to manufacture perfume in the flower after it is cut, such as tuberose for example.

Resin Absolute: generally applied to materials obtain directly from plant raw-materials by extraction with hot alcohol: once the alcohol has been recovered, what is left is referred to as the Resin Absolute.  As the product is often very thick and sticky, the recovered alcohol may be partially replaced by a high-boiling solvent such as Isopropyl Myristate when it is usually sold as ‘mobilised with N% of XX’.  Notable exceptions include the extraction product of Oakmoss with hot alcohol, which is usually called Oakmoss Resin; that of Orris is likewise called Orris Resin.

Benzoin resin from which Benzoin Resinoid is made

Resinoid:  A solvent extract of a resin-rich material containing natural exudate or dried plant material with a hydrocarbon solvent. Resinoids are generally viscous to semi-solid mixtures. They can be considered as being equivalent to concrètes but made from dead / dried (non-cellular) materials.

Spice/Herb Oleoresin: A solvent extract of a dried spice or herb, which is virtually free from the extracting solvent. It is used more-or-less exclusively by the food and pharmaceutical industries as a replacement for ground spices and spice tinctures.

Supercritical Fluid Extract This is an extract made using supercritical carbon dioxide (CO²) or another suitable supercritical fluid material as the solvent. Supercritical fluid extraction (SFE) of plant material with solvents like CO²,

propane, butane, or ethylene is increasingly being done. SFE allows the processing of plant material at low temperatures, hence limiting thermal degradation, and avoids the use of toxic solvents.  A common downside of SFE is that the resulting material may not be fully soluble in ethanol and in many cases further extraction with ethanol to produce, what is in effect an Absolute from SFE is conducted – these are sometimes sold as CO² Select Extract or, more intuitively as Ethanol Soluble SFE.

Tincture: An alcoholic or aqueous alcoholic extract of a natural raw material in which the solvent is left in the extract as a diluent. Tinctures are used both in the fragrance and pharmaceutical industries. The amount of alcohol in the tincture, which ranges from 20-95%, is standardized by the manufacturer.  See my post on Ambergris for an example of a tincture used in perfumery

 

Ambergris substitutes - clarification of terms.

I've written already about natural ambergris (also called Ambra) and mentioned there that most perfumery uses synthetic substitutes.

Here I'm setting out some of those substitutes (mainly synthetic, but including some naturals) and trying to sort out some of the confusion resulting from the fact that there are so many different products with very similar names.


The ambreine produced from labdanum, also sometimes confusingly called Cistus oil, is a steam distilled product from Cistus ladaniferus.  I have been told by a leading producer of both labdanum absolute and cistus essential oil that the difference between the two products is as follows: Cistus oils are produced by steam distillation of the entire top-growth (twigs, leaves, stems and flowers) of the Cistus ladaniferus plant - a cistus absolute is sometimes also produced from the top-growth.  Labdanum products, by contrast,  are produced from a gum-resin found on the roots of the plant, which are first washed and then mechanically agitated to separate the gum from the rest of the roots, an essential oil, absolute and resinoid of labdanum are all produced from this gum-resin.

Ambrarome (from Synarome) and Ambrain (from IFF) are similarly extracted by proprietary processes from the labdanum resin (referred to as gum-labdanum sometimes though I think incorrectly - see details in this post for definitions). These are highly animalic in smell and designed as plant-based alternatives to the traditional animal components of perfumery.

Ambrox is a term usually used to mean Ambrox DL or one of it's synonyms: quite different from the labdanum based materials because it's a brand name for a single synthetic molecule (though a mixture of isomers) which replicates one of the components of natural ambergris.  The term ambrox is sometimes used to mean any of a range of similar products, in particular Ambroxan / Ambrofix / Orcanox that are brand names for chiral isomers [specifically (-)-Ambroxide], which though similar, are not quite the same. In my work I mainly use Ambrofix, which is made by Givaudan from a natural starting material, though I do use some of the others too.

Just to confuse matters further there is also Ambrein which is the waxy substance that is the majority component of natural ambergris, the breakdown products of which give the precious scented molecules of ambroxide and others that have been replicated by the various brand-named products above.  When pure, ambrein is odourless.  Bo Jensen provides a good description of what's going on (scroll down to the text just below the whale pictures).  I also use several of the other substitutes mentioned by Bo Jensen in his article for particular purposes.

Further confusion often arises between Ambergris (Ambra) products and Amber - a term that in perfumery is sometimes used to refer to a product made from the fossil amber by destructive distillation of the waste and low-grade amber left over form the jewellery trade.  This is described by Arctander as having a "smoky, tarlike, resinous" odour "with a distinct resemblance to the smell of tanned leather".  He mentions that there is also a rectified version of this oil, which has been steam distilled as well, but he says that this is "very little used in perfumery".

More often however amber refers to a blend of ingredients intended to give an warm scent reminiscent of both ambergris and the appearance of fossil amber (which in its raw state has virtually no odour).  Such blends normally include labdanum, vanilla, benzoin and other ingredients; are are often used as fixatives.  Some of the products named in the first paragraph fall into this category, but many perfumery houses and others will have their own blend.

Musk

Musk is one of the most common elements in perfumes - some form of musk is included in virtually every fragrance on the market, but which form varies a great deal as there are a great many options.

At one time, musk came almost exclusively from various species of Musk Deer but this has almost entirely disappeared from use for ethical and cost reasons.

Moschus moschiferus - one of the species that were the original source of musk

Most fragrances now use some form of synthetic musk, but there are a few natural sources still sometimes used.  In particular ambrette seed oil (containing the chemical widely used in synthetic form as ambrettolide) and angelica root oil (now known to contain the chemical exaltolide, though this was not recognised until long after exaltolide had been made synthetically).

Some synthetic musks are crystalline solids and as a result are often sold either pre-diluted or ‘mobilised’ in something to make them liquid and easier to handle.

There are a huge number of musks on the market, these are some of those I use particularly like or find useful:


Ambrettolide this synthetic is the same as the musk in Ambrette Seeds - a very good quality diffusive musk, slightly fruity, very smooth and exalting.
Applelide an IFF product, this is relatively short-lived for a musk but has a strong, velvety top-note that give a great deal of richness and has a fruity aspect of apples as well.
Cashmeran also from IFF is interesting - liquid and easy to handle - has a spicy quality. When used successfully it is very warming and velvety.  Not everyone considers this molecule as a musk at all.
Celestolide crystals that are slow to dissolve in ethanol. Adds more brightness than the others, very good diffusion.
Civettone isn't widely used alone or available in small amounts. It is the musk component of natural civet paste and the synthesised version is used as part of civet recreations, arguably the most powerful fixative in perfumery. 
Ethylene brassylate (also called Musk T), widely available, liquid at room temp and cheap, good fixative properties and easy to use macrocyclic musk.
Exaltolide solid at room temp but melts easily, very widely available and used macrocyclic musk with a fairly strong, sweet-musk aroma. Not everyone can smell exaltolide but it's one of the finest musks you can use.
Exaltone is the key molecule in muskrat musk and although it can now be synthesised even the synthetic version is very expensive.  It is however incredibly persistent and, arguably, one of the best fixatives known to perfumery.  More animal smelling than most synthetic musk.
Galaxolide a polycyclic musk, very widely available and used, especially in functional products. Often sold as 50% in DEP or IPM as it’s so thick a liquid as to be virtually solid otherwise. A polycyclic musk which is not biodegradable and very persistent in the environment and people.
Habanolide a macrocyclic musk from Firmenich with a strong odour and slightly waxy and metallic freshness. 
Helvetolide another Firmenich product, this is unusual in having a strong top-note as well as the more usual persistence of musks.  It also has a fruity aspect  of pears.
Muscenone is one of the components of natural deer musk, very good fixative and diffusive qualities and has a stronger musky smell than the better-known muscone:
Muscone this is the main musk that is in musk deer pods but synthesised. Lovely fine musk that has the edge over the others for its erogenic quality l-Muscone is a more expensive and even finer quality - just the L isomer.  Both forms have a nice powdery quality.
Romandolide not so widely available, similar in scent to Galaxolide but alicyclic (or linear) and biodegradable: very useful and I'm in the process of phasing out galaxolide to be replaced by romandolide in all my retail range.
Tonalid polycyclic, crystalline solid again but a bit easier to dissolve than some. Often disparagingly referred to as ‘laundry musk’ it’s nevertheless a good fixative and very widely used.  Cheap enough for functional products and gives a very clean effect.
Velvione another macrocyclic, very fine musk of great diffusion, rather like ambrettolide but less fruity and even softer. A great exalting agent, it has little scent of it's own but has a big effect in a blend and gives a distinct powdery effect.


There are plenty of others. I nearly always use musks in combination rather than using just one in a composition. In particular you can get good effects by using very tiny amounts of ambrettolide or velvione alongside one of the cheaper musks. Both work well with Exaltolide and Romandolide.

Another option is Auratouch from Givaudan - a blend of several of their musk products which I believe also includes a captive.

Synthetic musks have also been the cause of some controversy and a number of them were found to be unstable, carcinogenic or environmentally damaging.

Musk Ambrette is prohibited by IFRA and Musk Ketone is banned in some countries even though it isn't restricted by IFRA.  Musk Xylene is banned throughout the EU and prohibited by IFRA.

Muscone, a macrocyclic musk

If you want to understand the different categories of musk (based on their chemical structure) and something of the history of their production the Wikipedia article on Synthetic Musks makes excellent reading.

Bitter Almond Oil

Bitter Almond Oil is one of those curious perfumery ingredients that isn’t at all what it appears to be: it almost certainly won’t have been made from almonds, bitter or otherwise, isn't bitter and may be natural or synthetic.

Bitter Almond Blossom

What is called Bitter Almond Oil and was originally and is still occasionally made from bitter almond kernels - Prunus amygdalus Amara - is now more usually made from apricot, plum, cherry or peach kernels (or by synthesis from various pre-cursors, most commonly toluene). It consists of about 99% Benzaldehyde whether made from a natural or a synthetic source, and may be sold as Bitter Almond Oil in either case.

When almonds are used it is the press-cake remaining after extraction of the fixed almond oil that is the starting point which is macerated in warm water prior to extraction. A substance called Amygdalin, present in all the kernels mentioned, is converted by enzymatic action into benzaldehyde and hydrocyanic acid (what is commonly called cyanide when people are talking about the poison, once also called Prussic Acid). There is enough cyanide present in about 10 drops of the crude oil to kill an average person, and it is poisonous by ingestion and by inhalation, so the oil is quite useless at this point as a flavour or perfume agent. The process is nearly identical when it is made from the kernels (stones) of apricots, plums, cherries or peaches.  


As an aside, amygdalin is also present in apple pips, so far as I know they have never been used as a commercial source of the oil, but if you’ve ever heard that apple pips are poisonous, now you know why.  In practice they don’t contain cyanide unless they are crushed up and fermented and tend to pass through the human gut whole, so if you’re in the habit of eating your apples core-and-all you’re not likely to come to any harm.

The crude oil is cleaned by alkali washing and rectification resulting in the nearly pure benzaldehyde that is sold widely as Bitter Almond Oil. Oddly enough it’s main use in flavouring is as a sweetener - so not only is in not usually made from almonds but it isn’t bitter either! The odour is familiar to most people as marzipan, which was traditionally made with about 1% bitter almond kernels ground up with the sweet almonds into a paste. Now it is more likely to be made with all sweet almonds and some benzaldehyde added to flavour it.

According to Arctander, Hydrocyanic acid smells rather similar to Benzaldehyde - though I don’t recommend testing that assertion.

Arctander also has this to say about the natural vs synthetic origins of the oil:

Bitter Almond Oil is very rarely produced from bitter almonds. If the oil is a natural distillate at all, it is most often produced from other kernels (see above). A large part of all the so-called bitter almond oil in the market is actually a refined synthetic benzaldehyde, supposedly free from chlorine. The labelling FFPA stands for “free from prussic acid” (old name for hydrocyanic acid). The abbreviation FFC means “free from chlorine”, and is obviously applied to synthetic products.

He goes on to say that some of the imitations of the natural distillate contain traces of (deliberately added) hydrocyanic acid and if completely free of chlorine, are thus identical with the natural product. I’ve no idea whether this kind of adulteration continues today, but it seems likely.

Benzaldehyde by the way isn’t very stable and tends to turn into Benzoic acid (white crystals that are essentially odourless) on exposure to air and consequently it is often sold with some ethanol added to improve stability.

Benzaldehyde is highly volatile liquid: a top note if you use it in perfumery and isn’t all that widely used. I happen to have some at the moment because one of the things I’m researching is a lilac fragrance, in which it is a component.


A draft of this material appeared on the fragrance discussion forum Basenotes in this post.

Books about Perfumes and Perfumery

There are quite a lot of books about on the subject of perfumes, perfumery and the making of perfumes and many of them are not all that helpful, so I’ve tried to gather together here some recommendations for books I’ve found to be particularly helpful or interesting.

Some books from the Pell Wall Perfumes bookshelf

First of all if you have not read  Patrick Süskind’s Perfume: the story of a murder you really should: besides offering a wonderful insight into the early days of perfume making it’s a fantastic (in both senses of the word) story of murder and obsession that keeps you turning the pages long after you should have gone to sleep.

While we’re on the early days of perfume, The Art of Perfumery by G.W. Septimus Piesse, first published in 1857 is well worth reading if you are interested in how perfumes were made in the 19th century: the book covers production methods and gives formulae as well as anecdotes and trenchant opinions that together make for a fun read: elements of it are still useful to the modern perfumer too.

One hundred years on and we get Steffen Arctander writing Perfume and Flavor Materials of Natural Origin - his work is unmatched and still qualifies as the standard work on the odour of raw materials throughout the industry.  I also have his Perfume and Flavor Chemicals Volumes 1&2 in CD form and although the range of synthetics in use has increased enormously since this was published in the 1960s it still provides a very useful insight into the majority of synthetic ingredients in use in modern perfumery.

Of similar vintage, but very different form is W. A. Poucher’s Perfumes, Cosmetics and Soaps, with special reference to Synthetics Volumes 1&2.  I have the 6th Edition from 1959, which is excellent but I’m told by people who have more recent editions that they are not nearly as good.  My copies are stuffed full of fascinating information, formulae for accords, descriptions of materials and scent notes and much more besides.  Excellent stuff.

If you are planning on learning to make fragrances of your own then a great starting place is Tony Curtis and David G Williams’ An Introduction to Perfumery which gives you much the same range of information as Poucher, but slightly better structured and vastly more up to date.  In addition you get a well structured learning plan and a series of exercises to build your skills.

For an overview of the reality of fragrance creation and the way fragrance companies work, as well as a dip into the cultural history of fragrances and a wealth of information more obviously associated with the title I can recommend The Chemistry of Fragrances: from Perfumer to Consumer, edited by Charles S Sell.  This volume includes essays by a number of other authors so you get a few different perspectives, but Charles’s own work is a real highlight as he’s such a readable author even if, like me, you don’t have a degree in organic chemistry.

If you are looking for something to help you understand how one fragrance is related to another then you could do worse than to invest in Michael Edwards' Fragrances of the World 2012 which catalogues all the great fragrances of the world according to type.

I could doubtless go on, but for the moment at least I’m going to stop there and publish this post.  Please feel free to add your own comment on these books or to make other recommendations of your own.