Basil is known as the king of herbs. Its Latin name basiliculm means king or royalty, suggesting that this is the herb most fit for consumption by royalty. While there are many different types of basil oils, Sweet Basil Oil distilled from the Ocimum Basilicum, a member of the mint family, is the primary product used in perfumery and flavoring applications.

The use of basil oil in flavoring is much more important than in perfumery. Fresh and dried basil leaves are used much more broadly in commercial and home cooking.

Basil notes are included in chypres, culinary perfumes, green accords, and fresh green modern styles. Arctander writes, “In chypres, crepe de chines and certain modern aldehydic and “green” perfume types, the oil can introduce very interesting notes. It blends well with the most varied types of perfume materials, e.g. opopanax or bergamot oil, isoeugenol or clary sage, methylionone or cyclamal, lime oil or oakmoss, hydroxycitronellal, etc.”

The challenge of identifying a characteristic “basil” scent is due to the wide variation in chemical composition across cultivars. One study by Liber et al. identified 5 different typologies from 27 cultivars: eugenol/linalool (30–35% linalool and 12–20% eugenol); linalool (52–66%); estragole/linalool (22–38% estragole and 21–37% linalool); (Z) methyl cinnamate (19–38%); and estragole (38–95%). This means that if one intends to use the essential oil in perfumery or aromatherapy, a chemical analysis (GCMS) from the seller would be preferred. Depending on the seller, different cultivars could be provided across lots such that the character of the oil using the same brand is entirely different.

Basil Aromatic Properties and Chemical Composition

Fresh, Floral, Woody: Linalool is common to all and is found at well above 50% of the total components in the linalool typology. Linalool is ubiquitous in plant materials and is used to give lift and freshness to heavy compositions when added on its own. Linalool has a fresh, floral, woody scent with citrus, rose, and and waxy notes. This material is widely used as a synthetic ingredient or natural isolate in modern perfumery. Linalool is relatively volatile, with about 12 hours substantivity on paper, making basil a top note in most compositions, albeit with longer duration than most citrus.

Anisic, Sweet, Fennel, Herbal: Estragole, which ranges from very low levels in the linalool type to up to 95% in the estragole type. Estragole is a relatively volatile compound, lasting 8 hours on paper, and lends an aroma of sweet anise, fennel, herbal, sassafras.

Spicy and Clove-like: Basil does have a fairly high level of eugenol depending on the type of basil cultivar (2-20%), which contributes to its spicy, clove-like scent. Eugenol is restricted by IFRA, including naturally occurring eugenol.

Camphorous and Medicinal: Eucalyptol, or 1,8-cineole, is often a common constituent (~2%), giving the expected scent of eucalyptus, camphor, and menthol. This is a more volatile chemical than linalool, so one may expect to smell this strong herbal note upon application, particularly when combined with the ~2% menthol content in the oil.

Citrus, Bright, Pine: Monoterpenes in basil include beta-ocimene, alpha-pinene, beta-pinene, limonene, and beta-myrcene. These compounds are volatile, with substantivity on paper ranging from 1-4 hours. As a whole, they provide a bright, citrus, pine, woody, herbal, and terpenic aroma.

Terpenic, Peppery, Herbal: Basil essential includes a range of sesquiterpenes and terpenes, many of which have terpenic, peppery, spicy, and herbal notes.

References

Liber Z., Carović-Stanko K., Politeo O., et al. Chemical characterization and genetic relationships among Ocimum basilicum L. cultivars. Chemistry and Biodiversity. 2011;8(11):1978–1989. doi: 10.1002/cbdv.201100039.