206 Handbook of herbs and spices
was lower (0.44%) than that of steam distilled herbage (1.2%). The steam distilled oil
contained 52.4% 1,8-cineole where as the hydrodistilled oil contained much less
(31.9%) cineole. The contents of camphor (19.7%), borneol (12.1%) and a-terpineol
(12.8%) were higher in hydrodistilled oil compared to the steam distilled oil.
Spearmint
Tsuneya et al. (1998) studied acidic components in Scotch spearmint oil (Mentha
gracilis Sole) and 46 acidic components (including 35 carboxylic acids and 11 phenols)
were identified. Three carboxylic acids peculiar to M. gracilis were identified from
spectral data: cis-2-pentylcyclopropane-1-carboxylic acid, 3-isopropenylpentane-1,5-
dioic acid and 3-isopropenyl-6-oxoheptanoic acid.
Platin et al. (1994) studied equilibrium distributions of key components of spearmint
oil in sub/supercritical carbon dioxide. Effects of temperature (at 35 ∞C, 45 ∞C or
55 ∞C) and pressure (10–110 atm) on the relative distribution coefficients of 12 key
components (6 monoterpenes, 3 monoterpenoids and 3 sesquiterpenes) of spearmint
oil (essential oil of Mentha cardiaca (M. gracilis); Scotch spearmint) at equilibrium
in dense CO 2 were investigated under conditions ranging from subcritical to supercritical
regions. At 35 ∞C all key components of spearmint oil were equally soluble in dense
CO 2 within the 12–102 atm pressure region. Vapour-pressure effects, coupled with
Table 11.17 Volatiles from rosemaryCompound % Compositiona-Pinene 5.5–26.0
Camphene 1.5–13.0
b-Pinene 2.60
Myrcene 1.50
D-3-Carene 2.30
Limonene 2.80
p-Cymene 1.80
1,8-Cineole 9.4–55.0
g-Terpinene 1.30
Terpinolene 0.50
Linalool 0.5–4.9
Camphor 5.0-26.4
Isoborneol 0.30
Borneol 1.1–5.5
Dihydrocarveol 0.13
Verbenone 0.0–14.1
Linalyl acetate 1.40
Bornyl acetate 1.90
b-Caryophyllene 1.40
a-Humulene 1.20
Methyl isoeugenol 0.50
Trans-b-farnesene 0.40
g-Muurolene 0.30
d-Candinene 1.20
b-Sesquiphyllandrene 1.30
Carophyllene oxide 0.60
Humulene epoxide 0.06
a-Bisabolol 0.78
Unidentified 1.93Source: Kumar et al. (2004).