Did you smell that?

Ladies, do these images look familiar?

Screen Shot 2017-04-06 at 3.11.22 PM

You probably have seen and smelled perfume before, and know some of the brands and scents by heart. (If you’re wondering, the perfumes above are: 1) Chanel No. 5 by Chanel, 2) Shalimar by Guerlain, 3) Opium by Yves Saint Laurent, and 4) Daisy by Marc Jacobs.)

Simply put, a perfume is a carefully balanced blend of odoriferous materials, where each material in the perfume plays a role in achieving the overall fragrance.

Historically, the art of perfumery has been known to ancient civilizations in Mesopotamia, Egypt, China and India. Perfumes in these eras were commonly used as incense, for aesthetic intentions and for embalming the dead in some cases. Nowadays, perfumes are used commonly for personal adornment, in religious ceremonies, for aromatherapy, and to improve or mask undesirable odours of various products.

Smell Aspect

Typically, odour can be divided into odour types and odour characteristics.

Odour type refers to the physical source an odour is obtained from. For example:

Odour type Examples
Floral Jasmine; Narcissus; Magnolia; Lilac; Rose; Ylang Ylang; Violet
Woody Cedarwood; Rosewood; Sandalwood
Musky Musk; Civet
Balsamic Benzoin; Frankincense; Labdanum; Myrrh; Vanilla
Earthy Oakmoss; Patchouli; Vetiver
Herbaceous Lavender; Rosemary; Sage
Minty Peppermint; Spearmint

On the other hand, an odour characteristic is described using the senses. For example:

Odour characteristic Examples
Dry Patchouli
Sweet Aniseed; Rose
Light Neroli; Lavender; Lemon
Heavy Tuberose; Ylang Ylang
Fresh Bergamot; Peppermint
Cool Menthol
Warm Ginger; Jasmine; Rose

Technical Aspect

In order to obtain the scent from naturally occurring materials, extraction is needed for to turn the natural raw material into the required product. Below are some extraction techniques that could be used to obtain perfumery ingredients.

1) Steam distillation

  • Steam from boiling water is passed through the raw materials, such as flowers and leaves – this process drives out the volatile fragrant compounds.
  • These compounds and steam pass through the condenser and settle in a Florentine flask – this allows for the easy separation of the fragrant oils from the water since the oils will float to the top of the distillate.
  • The watery distillate, by-product of distillation, are known as floral waters – this is because part of the constituents of the oils are slightly soluble in water.
  • Some essential oils that can be obtained by steam distillation are rose and orange flower oils; rose water and orange flower water are two important examples of floral waters used in perfumery.
  • A diagram below shows the steam distillation process:

Steam Distillation

2) Expression (a.k.a. cold pressing)

  • Expression is typically used for citrus fruits such as lemon, orange and bergamot.
  • The citrus peel is placed between a mechanical crusher to squeeze out the citrus oil, and the resultant liquid is allowed to settle before the essential oil is separated.

3) Enfleurage

  • Enfleurage is an old processing technique used in the South of France, and is a labour intensive procedure; it is rarely used nowadays.
  • It is used mainly for flower varieties, which after being plucked, continue to live and metabolise to produce fragrant materials.
  • In the enfleurage process, glass plates are covered with a thin layer of cold, purified fats (e.g. 75% lard and 25% tallow). These plates are placed in wooden frames known as chassis, covered with petals, and then stacked in piles.
  • The petals are removed and replaced by fresh ones frequently (e.g. 24 hours for jasmine, and 2-3 days for tuberose), and the process is repeated until the fats are saturated. The scent-saturated fats are melted and filtered. The product formed on cooling is known as pomade.
  • The pomade is further processed via alcoholic washing, filtering, freezing, re-filtering, and distillation under vacuum, until an absolute (enfleurages absolus) is obtained.

4) Solvent extraction

  • Solvent extraction is a more common and effective method of extraction.
  • Using volatile solvents (e.g. petroleum ether, hexane) at low temperature, the fragrant oil is extracted. Next, the solvent is driven off to yield a concrete or resinoid.
  • Concretes are the waxy masses that remained after the solvent extraction of various plant parts such as flowers. As waxes and colouring matter are also extracted along with the fragrant oil, concretes may be coloured at times. A concrete can be extracted with alcohol and further processed to form an absolute.
  • As the name suggests, resinoids are obtained from solvent extraction of resins, which are solid plant secretions. It is usually viscous and sticky in nature.

You may have noticed that the word absolute was mentioned a couple of times above. So what is an absolute? Simply put, absolutes are highly concentrated fragrance materials that is usually obtained through alcohol extraction from concretes, or from pomades via enfleurage. Absolutes are often expensive due to the low overall production yield. For instance, 1000kg of jasmine (that’s about 8 million flowers) can only yield 2.3kg of concrete: this amounts to just 1kg of absolute!

In essence (pun intended), the art and science of perfumery is not just about mixing some pleasantly smelling ingredients together guilelessly. Each fragrance material works in synergy to create the eventual scent that captures the hearts of women (and men, especially men) worldwide. By the way, Mother’s Day is coming soon, so perhaps this post will spark some inspiration for gifts for your mum. 🙂

– Ling Ling

 

References:

  • The Complete Guide to Aromatherapy. 2nd S. Battaglia, The International Cenre of Holistic Aromatherapy, 2003.
  • The Chemistry of Fragrances: From Perfumer to Consumer. 2nd C. S. Sell. Royal Society Of Chemistry, 2012.

Sources of images:

 

Advertisements

One thought on “Did you smell that?

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s