To Scent or Not To Scent (Part 1)

Per Fumus

Perfume has been been known to exist since the early civilizations.

The word 'perfume' is a derivative of the Latin word 'per fumus' which means through smoke. The people in ancient Egypt were the earliest people to discover perfume. And the use of perfume was in the form of burning of incense and aromatic herbs which were used in religious services. And the most frequently used ingredients were aromatic gums, grasses, frankincense and myrrh which were gathered from trees.

Kyphi, was a famous burnt incense. It is a very odorous mixture which comprised of cinnamon, cassia bark, the rhizomes of cypress and sweet flag, cedar, myrrh, frankincense, Matsic tree, juniper berry, seeds of fenugreek, pistachio and edible shoveler duck. These ingredients were crushed and mixed together with wine, raisins and honey. Not only was it used as an incense, it was also used as a potion and as a salve.

Perfume

In today's world, perfume is basically a mixture of essential oils or aroma compounds, fixatives and solvents used to give the human body, objects, and living spaces a 'pleasant smell'!

1. Essential Oils

Essential oil is a concentrated hydrophobic liquid which contains volatile aroma compounds from plants. Essential oils are also known as volatile oils, ethereal oils/aetherolea or just simply, 'oil of' the plant which they were extracted from. An example would be 'oil of lavender'.

Essential oil carries a distinctive scent or characteristic of the plant.

Generally, essential oils are extracted by distillation. Solvent extraction is another method in which the essential oil is extracted.

Essential oils are used in perfumes, cosmetics, soaps, for flavoring food and drinks, adding scents to incenses and household cleaning products. It is also widely used in aromatherapy.

2. Aroma Compounds

An aroma compound is a chemical compound that has an odour or smell. Aroma compounds are also known as odorant, aroma, fragrance or flavour.

In order for a chemical compound to have a smell or odour, the compound needs to be volatile in order for it to be transported to the sense of smell (olfactory system) in the upper part of the nose and it needs to be of a sufficiently high concentration in order to interact with one or more of the olfactory receptors.

Aroma compounds are found in food, wine, spices, perfume, fragrance oils and essential oils. Aroma compounds form biochemically during the ripening of fruits. Aroma compounds also form during the fermentation of wine.

Aroma compounds are also added to dangerous odourless substance such as propane, natural gas and hydrogen as a warning.

Many aroma compounds play a significant role in the production of flavourants, which are used in the service industry to flavour, improve, and basically used to increase the appeal of their products.

3. Fixatives

Fixatives are natural or synthetic substances used to reduce the evaporation rate and improve stability when added to more volatile components. By doing so, the final product will be able to last longer while the original fragrance is maintained. They are indispensable commodities to the perfume industry.

Some examples are ambergris, sandalwood, musk, vetiver, orris root and bergamot orange.

a. Ambergris


Ambergris is a solid waxy, flammable substance of a dull gray or blackish colour which is produced by the sperm whale's digestive system and is excreted out by regurgitation. A freshly produced ambergris has a marine, fecal ordour. But as it ages, it acquires a sweet, earthy scent which can be likened to the fragrance of rubbing alcohol (isopropanol) without the vaporous chemical astringency.

In the early times, ambergris is used as a fixative in perfumery. Because of the vulnerability of the sperm whale species, it was banned in the 1970s in many countries. Today, ambroxan, a synthetic which emulates the natural ambergris is used widely in perfumery.

b. Sandalwood


Sandalwood essential oils provide perfumes with a striking wood base note. But as a fixative, it is used in smaller proportions to enhance the head space of other fragrances.

Sandalwood trees are endangered due to over-harvesting, thus causing the natural oil to be very costly. Hence, Isobornyl cyclohexanol (ICBH) is the synthetic fragrance chemical produced as an alternative (and very much cheaper compared) to the natural sandalwood.

c. Musk

Musk is a class of aromatic substances used as base notes in perfumery. Musk was originally extracted from the gland of the male musk deer. Natural musk was used extensively in perfumery until the late 19th century. Musk is described to be earthy and woody and akin to the ordour of baby's skin.

Angelica archangelica or Abelmoschus moschatus are plants that produce musky smelling macrocyclic lactone compounds. These compounds are widely used in perfumery as substitutes for animal musk or to alter the smell of mixture of other musks.

Since the musk deer is an endangered species and obtaining musk from plants are costly, nearly all musk fragrance used in perfumery today are synthetic, which is sometimes called the 'white musk'.

Synthetic musk can be divided into three major classes:
* Aromatic nitro musks
* Polycyclic musk compounds
* Macrocyclic musk compounds

The aromatic nitro musks and polycyclic musk compounds are used extensively in the cosmetics and detergent industry. However, these two are known to contain carcinogenic properties. Thus, macrocyclic musk is deemed to be a better replacement.

An example of a polycyclic musk is the galaxolide which is found in laundry detergent to mask the smell of detergent chemicals. Galaxolide is also the aroma compound in laundry detergents which gives the washed laundry the 'clean scent'. Consumers today have been brainwashed to expect and demand that laundry detergents produce this 'clean scent'.

To read more on galaxolide, click here.

d. Vetiver

Due to its excellent fixative properties, vetiver is widely used in perfumes. It is contained in almost all of western perfumes (Lavania). Vetiver is a more common ingredient in men's fragrances such as Eau de Sauvage, Zizan by Ormonde Jayne and Vetiver by Occitaine.

e. Orris Root

Once upon a time, the Orris root was very important in the western herbal medicine. Today, it is mainly used in the perfumery as a fixative and base note. It is also widely used as a fixative in potpourri. The smell of Orris root is akin to the smell of violets.

f. Bergamot Orange

This fruit is not grown for consumption. The Bergamot peel is used in perfumery as it is able to combine itself with an array of scents to form a bouquet of aromas which complement each other. Many of the perfumes which are produced contain the bergamot essential oil.

An interesting thing to note is that the Bergamot contains extremely large amount of polyphenols!


4. Solvents

A solvent is a liquid, solid or gas which dissolves another solid, liquid or gaseous solute, resulting in a solution that is soluble in a certain volume of solvent at a specified temperature. The common solvent which is used in perfume is ethanol.