Basil oil (estragole type)

Other comments :

Adulterations exist, especially with Copaene, Caryophyllenes, Germacrene-D.
Usually, Egypt-originated Linalool chemotype of basil is used in perfumery, and over all 50% Linalool qualities (high price) or the one with 42 to 48% Linalool (affordable price).

Stability :

The terpenes identified in this raw material can polymerize when they are oxidized
Aromatic compounds can be chromophoric and cause a coloration of the oil, especially in alkaline bases

Uses in perfumery :

Used in masculine notes, fougere, chypre-fruity, in small quantities.

Chemotypes :

Around 160 species of basil are reported (Ocimum). These can be classified in four major groups :
Eugenol and Thymol chemotypes : Ocimum Gratissimum L. (from Sri-Lanka) or Ocimum tenuifolium (from India - Eugenol ≤ 60% ou Estragole ≤ 85% depending on varieties) ou Ocimum Viride (Thymol ≈70%). The second one is very rich in Estragole and can be used to extract natural Estragole.
Estragole chemotypes : Ocimum basilicum var. basilicum so-called ''common basil '' . This variety is the most used in perfumery and is made in majority of Estragole.
Ocimum basilicum var. letuce leaf, rich in Linalool
Ocimum basilicum var. ''grand vert '' - Basilic (Linalool Chemotype) EO - also rich in Estragole and Linalool.
Citral chemotypes : Ocimum americanum (Mediterranean), so-called ''Lemon Basil ''. Is also rich in Linalool and Estragole (more floral smell but inferior yield)
Camphor chemotypes : Ocimum kilimandscharicum, also cultivated as a substitute for camphor tree.
Other species : Ocimum canum containing a lot of Methyl Cinnamate.

Extraction process :

The basil harvest takes place from July to December. During this process, the aerial flowery part of the plant is harvested by hand, the top of the plant are dried before the steam distillation. The essential oil can be obtained through the flowers and the whole plant. Generally the treatment is done on the flowers during the first three to four years (yield ≈0.4%), then on the whole plant (yield ≈0.1%). The first distillation fraction takes about 4 hours to be collected.
Supercritical CO₂ extractions also exist for this plant, as well as ''terpene-free '' extracts.
Given the large amount of terpenes in the plant, it is strongly advised to extract it as soon as possible. Too much time between harvesting and distillation would dry the plant and the resultant EO would be less representative, accompanied by a raise of the Linalool and Eugenol rates in the EO. Usually, harvesting is made during sunny days, with no rain the day before. It is made in the morning, to avoid drying of the plant.

Geographic origin :

Data not available.