Introduction — What is a Musk?

Dr. Philip Kraft in the book “Chemistry and Technology of Flavors and Fragrances” explains: Musk is the dried secretion from an internal pouch found between the hind legs of the male musk deer Moschus ssp., which resembles an ordinary deer with hare-like long ears, grey-brown body colour and two canine teeth protruding from its upper jaw.

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Its intensely smelling secretion serves for both territorial boundary marking and for attracting female partners over large distances, i.e. as a pheromone. To harvest the secretion, the animal was traditionally hunted. The main hunting season was in February and March, when hunger forces the animals to leave their inaccessible hiding-places in the mountains. After killing the animal, the pouch was removed with the outer covering of hair and hide, and dried in the sun or on a heated stove. Most of the hair and hide was removed, and the musk pods were soaked in water and then opened to yield fatty brownish grains. By extraction of these musk grains with alcohol, tinctures were prepared that were directly used in perfumery.

The best quality was Tonquin musk from Tibet and China, followed by Assam and Nepal musk, while Carbadine musk from some Russian and Chinese Himalayan regions was considered inferior. To obtain 1 kg of musk grains, between 30 and 50 animals had to be sacrificed, and thus musk tinctures were very expensive perfumery ingredients. At the beginning of the nineteenth century, the price of Tonquin musk grains was about twice their weight in gold. But despite this high price, musk tinctures were still used in perfumery till about 1979, when musk deers were protected from extinction by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) and complimentary national laws. Today, natural musk, the quantity legally permitted by CITES as well as that poached and illegally traded, continues to be used only in traditional east Asian medicine, as a sedative or stimulant to the heart and nerves, and most importantly as an aphrodisiac.

In the book “The chemistry of Fragrances, David Pybus and Charles Sell” it is said: The original musk components of perfumes were extracted from animal sources. The two major ones were musk and civet, which were extracted from the anal glands of the musk deer and the civet cat, respectively. In both cases, the extracts have a strong animalic character arising from compounds such as indole and skatole (2-methylindole). The musk deer (Moschus moschiferus) is found in central Asia and natural musk is often called musk Tonkin, to denote the region of its origin. The civet cat (Viverra civetta) is found in Africa and Asia, Somehow, early perfumers recognized that under this animalic, and not entirely pleasant, note lay a rich, sweet character which serves not only as a perfume component in its own right, but also to ‘fix’ other notes. Fixation is a property of some perfume components, usually the higher boiling ones, that enables them to fix or hold back the more volatile notes so that they evaporate less quickly. The fixatives are therefore important in blending all of the perfume components so that the character does not change rapidly as each ingredient evaporates in turn. 

Muscone and civetone are the most important odor components of musk and civet respectively. Ambrettolide is a plant product, occurring in the seeds of the ambrette plant (Abelmoschus moschatus Moench, syn. Hibiscus abelmoschus) which is cultivated in Madagascar, the Seychelles, Colombia and Equador. 

Synthetic Musks

Synthetic musks, known as white musks in the perfume industry, are a class of synthetic aroma compounds to emulate the scent of deer musk and other animal musks (castoreum and civet). 

Musks have a clean, smooth, and sweet scent lacking the fecal notes of animal musks. They are used as flavorings and fixatives in cosmetics, detergents, perfumes, and foods, supplying the base note of many perfume formulas. Most musk fragrance compounds used in perfumery today is synthetic. 

Macrocyclic

Muscone
Civettone
Exaltone
Exaltolide
Ambrettolide
Globanone
Musk t93
Cervolide
Exaltenone
Muscenone
Velvione
Habanolide
Nirvanolide
Cosmone
Polvolide
Aurelione

Polycyclic

Phantolide
Versalide
Tonalide
Celestolide
Galaxolide
Cashmeran
Traseolide
Vulcanolide

Nitromusks

Musk Baur
Musk Xylene
Musk Ambrette
Moskene
Musk Tibetene
Musk Ketone

Alicyclic

Helvetolide
Romanolide
Serenolide
Sylkolide
Alpinolide

How to recognize (or go close to understand) a musk family by it’s smell

Recognizing musks by smell, for a non-experienced nose can be challenging.
Here’s a quick guide on how to.

• If the Musk has a sweet and soft character, then it’s very likely to be a Polycyclic Musk.

• if the Musk has a cosmetic, skin like character, it’s very likely to be Macrocyclic One

• If the Musk has an ambrette note (slightly powdery as well), our choice will be Exaltolide or Ambretolide (the last one will have fruity ambrette seed impact).

• If the Musk has an animalic nuance, Nitromusk would be a common choice.

• If the Musk has a floral undertone, i’ll be Most likely a linear (alicyclic).

Sources and informations

• O.P. David with The Updated Timeline of Musks — Via LinkedIn

• A conversation with Dr. Philip Kraft. Molecular designer at Givaudan

• H. U. Daeniker, A. R. Hochstettler, K. Kaiser and G. C. Kitchens, J. Org. Chem., 1972, 37, 1.

• B. A. McAndrew, S. E. Meakins, C. S. Sell and C. Brown, J. Chem. Sac., Perkin Trans. I, 1983, 1373.

• P. J. Teisseire, Chemistry of Fragrant Substances, VCH, 1993.

• G. Wagner, J. Russ. Phys. Chem. SOC.,1899,31,690.

• H. Meerwein, Ann., 1914,405, 129.

• E. W. Spanagel and W. H. Carothers, J. Am. Chem. SOC.,1935,57,929. L. Ruzicka and W . Brugger, Helv. Chim. Acta, 1926,9, 389.

• M. Stoll and A . Rouve, Helv. Chim. Acta, 1934,17, 1283.

• The chemistry of Fragrances, DAVID PYBUS and CHARLES SELL