Birch

Natural & syntheticPOPULAR & WEIRDmedicinal · fresh · camphoraceous

Seven perfumesOne of them is looking at you

Top·HeartPyramid

5/5Strength

—Tenacity

—Origins

Specimen

Betula lenta

Natural / Synthetic

Definition

Birch covers two materials: sweet birch oil from Betula lenta, and birch bark tar, a substance derived from birch tree bark. Sweet birch oil smells sweet, aromatic, spicy and herbal, with a phenolic nuance.

MEDICINAL MINTY SWEET WOODY CAMPHORACEOUS AROMATIC PHENOLIC

Sweet birch, black birch, cherry birch, mahogany birch, spice birch

Type: Ingredient
Olfactive family: Aromatic
Subfamily: Classic aromatics
Cluster: Aromatic-medicinal
Source: bark

Instruments

Pyramid

TTop

HHeart

BBase

5/5Strength

Very high

odour strength

Tenacity on blotter

Excellent (methyl salicylate)

Scent

Methyl salicylate has a sweet, fruity odor reminiscent of root beer, but it is often associatively called minty. Its aroma is described as wintergreen, minty, sweet, root beer, aromatic, phenolic and camphoraceous. Another description gives it an intensely sweet-aromatic character with a characteristic wintergreen note, a creamy-fruity top note, a phenolic-medicinal character and a sweet-woody dryout. The odor type of sweet birch oil is minty. In North America the smell is read as refreshing and minty, in Europe as medicinal, like a liniment. In fragrances, birch bark tar imparts a leathery, smoky note.

In PREMIEREPEAU

DISCOVERY SET7 × 2 ml →EXTRAIT DE PARFUMThe seven extraits →

The Molecule — Manufacturers & Variants

The Full Story

Sweet birch (Betula lenta) is a species of birch native to eastern North America. Its native range runs from southern Maine west to southernmost Ontario, and south in the Appalachian Mountains to northern Georgia.

Sweet Birch Oil — Source and Chemistry

The twigs of Betula lenta, when scraped, have a strong scent of wintergreen due to methyl salicylate, which is produced in the bark. Methyl salicylate, C₈H₈O₃, is the methyl ester of salicylic acid. Oil of wintergreen is manufactured from some species of birch, but these deciduous trees are not called wintergreens. Natural wintergreen oil can be distinguished from artificial oil by gas chromatography and by gas chromatography isotope ratio mass spectrometry.

Methyl Salicylate in Use

Methyl salicylate is used in high concentrations as a rubefacient and analgesic in deep heating liniments. Artificial wintergreen oil, which is pure methyl salicylate, is used in microscopy because of its high refractive index. Most instances of human toxicity due to methyl salicylate are a result of overapplication of topical analgesics, as skin absorption occurs easily. Methyl salicylate is a restricted substance under Annex III of EU Cosmetics Regulation 1223/2009. It has a CMR classification under EU CLP Regulation.

Birch Bark Tar

Birch bark tar is mainly composed of triterpenoid compounds of the lupane and oleanane family. The most characteristic molecules are betulin and lupeol, which are also present in birch bark. Birch bark tar oil has strong antiseptic properties, owing to a large amount of phenol derivatives and terpenoid derivatives. Birch bark tar has also been used as a disinfectant, in leather dressing, and in medicine. It is also one of the components of Vishnevsky liniment, and birch bark tar oil is an effective repellent of gastropods.

The Black Birch Tree

Betula lenta is a medium-sized deciduous tree reaching 30 metres tall, exceptionally to 35 metres, with a trunk up to 60 cm in diameter. The wood of black birch is heavy and is used for furniture, millwork and cabinets. Birch sap can be boiled the same as maple sap, but its syrup is stronger, like molasses. The syrup can be used to make birch beer. Boiling also destroys volatile quantities of wintergreen oil.

Silver Birch

Betula pendula, the silver birch, is a species of tree in the flowering plant family Betulaceae. The trees can reach a height of 30 m, and have white bark that sheds regularly. It is native to Europe, Morocco, temperate Asia, Canada, and Alaska.

History

Methyl salicylate was first isolated in 1843 from the plant Gaultheria procumbens by the French chemist Auguste André Thomas Cahours, who identified it as an ester of salicylic acid and methanol. Neanderthals produced tar through dry distillation of birch bark as early as 200,000 years ago. Russia leather is a water-resistant leather, oiled with birch bark oil after tanning. It was a major export good from seventeenth- and eighteenth-century Russia. The oil impregnation also deterred insect attack and gave the leather a distinctive and pleasant aroma that was seen as a mark of quality. Birch bark tar oil was used in the eighteenth century alongside civet and castoreum and many other aromatic substances to scent the fine Spanish leather Peau d'Espagne. At the turn of the twentieth century, birch bark tar had become a specialty fragrance material in perfumery.

Did You Know?

Black birch was once harvested extensively to produce oil of wintergreen, and the tree was borderline endangered until synthetic oil of wintergreen appeared in the 1950s–60s. A 5,000-year-old piece of chewing gum made from birch bark tar, still bearing tooth imprints, was found in Kierikki, Finland. A different chewing gum sample, 5,700 years old and found in southern Denmark, yielded a complete human genome and oral microbiome.

Extraction & Chemistry

Extraction method

In the past, methyl salicylate was commonly distilled from the twigs of Betula lenta (sweet birch) and Gaultheria procumbens (eastern teaberry or wintergreen). Commercial methyl salicylate is now synthesized. Methyl salicylate can be produced by esterifying salicylic acid with methanol. Birch bark tar is synthesized by dry distillation of birch tree bark. In the single-pot method, the birch bark is heated under airtight conditions, and the final product consists of tar and the ashes of the bark.

Formula: Complex natural mixture (key constituents: methyl salicylate C₈H₈O₃; betulin; lupeol)
CAS: 68917-50-0 (sweet birch oil); 8001-88-5 (birch tar oil)
Botanical: Betula lenta
Appearance: Colorless to pale yellow clear liquid (sweet birch oil)
Odour strength: Very strong (methyl salicylate)
Lasting power: Excellent (methyl salicylate)
Synonyms: Sweet birch, black birch, cherry birch, mahogany birch, spice birch

IFRA status

See note

IFRA Standard « Birch wood pyrolysate » (Amendment 47)

Physical properties

Boiling point: 222.6 °C (methyl salicylate)
Flash point: 96 °C (methyl salicylate)
Specific gravity: 1.14100 to 1.19100 @ 25.00 °C (sweet birch oil)
Refractive index: 1.50700 to 1.54700 @ 20.00 °C (sweet birch oil)

In Perfumery

Methyl salicylate is produced synthetically and used as a fragrance and as a flavoring agent. It is used in low concentrations (0.04% and under) as a flavoring agent in root beer, chewing gum, mints and medicine. Birch bark tar is a specialty fragrance material, used as a base note especially in fragrances of the leather and tobacco genre. To a lesser extent it is used in Chypres, especially Cuir de Russie perfumes and fragrance bases, typically together with castoreum and isobutyl quinoline. Birch bark tar is also used as an ingredient in some soaps, although other tars with an equally phenolic and smoky odor, such as pine and coal tar, are more commonly used in soaps as a medicating agent.

Role in the formula

01modifier

02top-note accent

03aromatic freshener

04blender

Available as

essential oil synthetic (methyl salicylate)