d content of olive oil varies very considerably. Very
fine oils contain less than 1 per cent. acidity; commercial oils may be
graded according to their free acidity, _e.g._, under 5 per cent., under
10 per cent., etc., and it entirely depends upon the desired price of
the resultant soap as to what grade would be used. The following is a
typical sample for use in the production of high-class toilet soap:--

_________________________________________________________
| | | | |
| Saponification | Acidity | Titre, | Refractive |
| Equivalent. | (as Oleic Acid) | deg.C. | Index at |
| | Per Cent. | | 15 deg. C. |
|________________|_________________|________|____________|
| | | | |
| 288 | 1.8 | 21 | 1.4704 |
|________________|_________________|________|____________|

Olive oil should absorb 80 to 83 per cent. iodine.

_Olive-kernel oil_, more correctly termed _Sulphur olive oil_.

The amount of free fatty acids is always high and ranges from 40-70 per
cent., and, of course, its glycerol content is proportionately variable.
The free acidity increases very rapidly, and is, doubtless, due to the
decomposition of the neutral oil by the action of hydrolytic ferment.

A representative sample of a parcel tested:--

_______________________________________________
| | | |
| Saponification | Acidity | Refractive |
| Equivalent. | (as Oleic Acid) | Index at |
| | Per Cent. | 20 deg. C. |
|________________|_________________|____________|
| | | |
| 298 | 40.96 | 1.4666 |
|________________|_________________|____________|

_Palm oil_ is produced from the fruit of palm trees, which abound along
the west coast of Africa. Lagos is the best quality, whilst Camaroons,
Bonny, Old Calabar and New Calabar oils are in good request for
bleaching purposes.

Analysis of typical samples of crude palm oil has given:--

_________________________________________________________
| | | | |
| Saponification | Acidity | Titre, | Water and |
| Equivalent. | (as Oleic Acid) | deg.C. | Impurities, |
| | Per Cent. | | Per Cent. |
|________________|____