Chemistry of Essential Oils

EUTACE^ 437

Specific gravity 0-888 to 0-897

Optical rotation - 1° to - 8°

Eaters 50 to 70 per cent.

Schimmel & Co.

1

give the following as the characters of petit-grain

oils of various origins :—

Origin.

Calabria.

Spain

Jamaica.

West Indies.

South America

Syria

Specific Gravity.

0-8746

0-8849

0-8846

0-8531

0-887

0-8857

Rotation.

+ 18°

+ 8° 25'

• 6° 30'

• 43° 36'


• 2°

• 3° 24'

Esters.
26-3 per cent.
28-6
28-7
2-1
36-5
27-1'
It is obvious that the W. Indian sample is not a normal petit-grain
oil at all, but has been distilled chiefly from immature orange fruits.
The twigs and leaves of the lemon, lime, and mandarin trees also
yield similar oils, which have been termed " petit-grain oils ". The
lemon product has been termed " oil of petit-grain citronnier ".
Boure-Bertrand Fils^1 have prepared four different petit-grain oils
from the branches of the bitter orange, the sweet orange, the lemon, and
the mandarin-tree, and have found these oils to possess the constants
given below :—

«*»" ....

oD.

SaponifL-ation Value

Ester Value after Acety

lation.

Solubility

Sweet Orange.

0-8980

- 4° 20'

161-4

203-0

In 3-5 vols.

70 per cent.

Alcohol.

Bitter Orange.

0-8584

+ 53° 52'

12-5

47-4

In 0-5 vols.

90 per cent.

Alcohol.

Lemon.

0-8806

+ 30° 44'

43-8

130-6

In 1 vol.

85 per cent.

Alcohol.

Mandarin.

1-0643

+ 2° 20'

265-0

In 1 vol.

90 per cent.

Alcohol.

The oil distilled from the corresponding parts of the lemon tree has

an odour resembling that of petit-grain oil, with a secondary odour of

lemon. It has the following characters :—

Specific gravity 0-870 to 0-895

Optical rotation + 14° ,, + 35°

Ester value 14 ,, 14 „ 46

Aldehydes 20 to 30 per cent.

It contains camphene (?), limonene, geraniol, linalol (?) and citral.

Jeancard and Satie give the following figures for the " petit-grain "

oil of lemon :—

Specific Gravity. Rotation. Esters.

Lemon Petit-grain.. 0-8763 + 13° 20' 12-25 per,cent.

Mandarin petit-grain oil has the following characters :—

Specific gravity 0-990 to 1-064

Optical rotation + 3° „ + 8°

Saponification value 150 ,, 190

The oil appears to vary in character to a considerable extent according

to the proportion of twigs and leaves present in the distillation material.

This oil may contain 65 per cent, of methyl-anthranilate.

(^1) Bulletin, October, 1910, 42.