Chapter V

=Cocoanut Oil.=—This oil, after special refinement, is extensively used in margarine and chocolate-cream manufacture, and is also sold under various fancy names as _vegetable butter_. There are two principal commercial varieties, Cochin and Ceylon, the former obtained from Cochin (Malabar) or the Philippine Islands, and the latter from Ceylon. The following are analyses of typical samples:—

+--- -------+----------------+-------------+--------+------------+
| | | Acidity (as | | Refractive |
| | Saponification | Oleic Acid) | Titre, | Index at |
| | Value. | per cent. | °C. | 25 °C. |
+-----------+----------------+-------------+--------+------------+
|Cochin oil | 255 | 1·5 | 23·5 | 1·4540 |
|Ceylon oil | 258·2 | 5·47 | 23 | 1·4535 |
+-----------+----------------+-------------+--------+------------+

=Maize Oil=, expressed from maize, and obtained chiefly from the United States, is occasionally used as an edible oil. A sample of refined maize oil has given the following figures on analysis:—

+---------+--------------+------+-----------+--------+----------+
| Specific| | |Acidity (as| |Refractive|
| Gravity |Saponification|Iodine|Oleic Acid)| Titre, | Index at |
|at 15° C.| Value. |Value.| per cent. | °C. | 20° C. |
+---------+--------------+------+-----------+--------+----------+
| 0·9243 | 192 | 123 | 0·40 | 17·2 | 1·4766 |
+---------+--------------+------+-----------+--------+----------+

=Cotton-Seed Oil.=—This is obtained by expression from the seeds of the various kinds of cotton tree, grown extensively in America, Egypt, and India. A considerable quantity of the oil is expressed from the seed in this country, principally at Hull. The refined oil is used in making artificial butter, and also for culinary purposes. The best cotton-seed oil, used for margarine manufacture, is sold under the name of “butter oil.” The following are typical figures for a refined cotton-seed oil:—

+---------+--------------+------+-----------+------+----------+
| Specific| | |Acidity (as| |Refractive|
| Gravity |Saponification|Iodine|Oleic Acid)|Titre,| Index at |
|at 15° C.| Value. |Value.| per cent. | °C. | 20° C. |
+---------+--------------+------+-----------+------+----------+
| 0·9229 | 193 | 115 | 0·24 | 33·6 | 1·4721 |
+---------+--------------+------+-----------+------+----------+

=Cotton-Seed Stearin.=—This is the solid residue remaining when the deposit obtained from ordinary refined cotton-seed oil by chilling is pressed. Its consistency is very similar to that of butter, and it is used in the preparation of some artificial butters. Its average properties are as follows:—

+----------------+--------+-----------------+--------+
| | | Acidity | |
| Saponification | Iodine | (as Oleic Acid) | Titre, |
| Value. | Value. | per cent. | °C. |
+----------------+--------+-----------------+--------+
| 195 | 93 | 0·05 | 38 |
+----------------+--------+-----------------+--------+

=Olive Oil.=—Edible olive oil is obtained by expression from the fruit of the olive tree, and is largely used as salad oil, in cookery, and for tinning sardines. Olive trees are grown extensively in nearly all the countries bordering on the Mediterranean Sea, also to a considerable extent in California. The oil obtained from their fruit varies a good deal in quality, according to its source, oils from Leghorn or Gallipoli being the most esteemed. The following figures were given by a typical high-class oil:—

+----------------+--------+-----------------+--------+------------+
| | | Acidity | | Refractive |
| Saponification | Iodine | (as Oleic Acid) | Titre, | Index at |
| Value. | Value. | per cent. | °C. | 20° C. |
+----------------+--------+-----------------+--------+------------+
| 190 | 89 | 1·8 | 21 | 1·4704 |
+----------------+--------+-----------------+--------+------------+

=Arachis Oil (Earth-Nut or Pea-Nut Oil).=—This oil, used occasionally in margarine to reduce its firmness, and a useful table oil, is obtained from the nuts of _Arachis hypogæa_, a herb cultivated largely in North America, India, and Western Africa. Most of the oil is expressed in Southern France, and its chief use appears to be as an adulterant or substitute for olive oil, which it closely resembles in many respects. The following figures were given by a sample of the refined oil:—

+---------+--------------+-------+-----------+------+----------+
| Specific| | |Acidity (as| |Refractive|
| Gravity |Saponification| Iodine|Oleic Acid)|Titre,| Index at |
|at 15° C.| Value. | Value.| per cent. | °C. | 20° C. |
+---------+--------------+-------+-----------+------+----------+
| 0·9205 | 193 | 87 | 0·22 | 24 | 1·4712 |
+---------+--------------+-------+-----------+------+----------+

=Sesame Oil.=—This oil is frequently employed in margarine manufacture, its use to the extent of 10 per cent. being compulsory in Germany and other countries, in order to simplify the detection of adulteration of butter with butter substitutes. It is largely expressed in Southern France from the seeds of the sesame plant, which is grown in the Levant, India, Japan, and West Africa. A representative sample gave the following results:—

+---------+--------------+------+-----------+------+----------+
| Specific| | |Acidity (as| |Refractive|
| Gravity |Saponification|Iodine|Oleic Acid)|Titre,| Index at |
|at 15° C.| Value. |Value.| per cent. | °C. | 20° C. |
+---------+--------------+------+-----------+------+----------+
| 0·9227 | 190 | 110 | 1·84 | 22·8 | 1·4731 |
+---------+--------------+------+-----------+------+----------+

=Palm-Nut Oil (Palm-Kernel Oil).=—This oil is obtained by expression or extraction in Europe from the kernels of the palm-tree fruit imported from Africa. It very closely resembles cocoanut oil in character and is used for similar purposes. The following results were obtained with normal samples of English and Hamburg oils respectively:—

+----------------+-----------------+--------+------------+
| | Acidity | | Refractive |
| Saponification | (as Oleic Acid) | Titre, | Index at |
| Value. | per cent. | °C. | 20° C. |
+----------------+-----------------+--------+------------+
| 245 | 4·4 | 24 | 1·4553 |
| 243 | 7·7 | 23·8 | 1·4553 |
+----------------+-----------------+--------+------------+

=Sunflower-Seed Oil= is expressed from sunflower seeds, the principal source of which is Southern Russia and Caucasia. It is also intended to cultivate them in South Africa, recent experiments having been found satisfactory. The following figures were obtained with a typical sample of the oil:—

+----------+----------------+--------+-----------------+--------+
| Specific | | | Acidity | |
| Gravity | Saponification | Iodine | (as Oleic Acid) | Titre, |
|at 15 °C. | Value. | Value. | per cent. | °C. |
+----------+----------------+--------+-----------------+--------+
| 0·9259 | 191 | 126·2 | 0·81 | 17 |
+----------+----------------+--------+-----------------+--------+

=Cacao Butter=, =or Oil of Theobroma=, is expressed from the beans of Theobroma Cacao, which is grown in Central America, and is the source of ordinary cocoa. It is used in pharmacy, but is principally employed in the manufacture of chocolate cream (vide Chapter VII. p. 84), the supply of which is very much inferior to the demand. It is a yellowish white, brittle solid, at the ordinary temperature, bleaching with age, and the following figures are typical of those given by an average sample:—

+----------------+-----------------+--------+--------+
| | Acidity | | |
| Saponification | (as Oleic Acid) | Titre, | Iodine |
| Value. | per cent. | °C. | Value. |
+----------------+-----------------+--------+--------+
| 193 | 1·1 | 47·9 | 33·6 |
+----------------+-----------------+--------+--------+

=Palm Oil.=—This is obtained from the fruit of the palm trees grown extensively along the West Coast of Africa. There are many qualities, that from Lagos being the best. The oil is occasionally employed in the manufacture of margarine, to which it imparts a yellow colour. Its use was recently the subject of an action in the United States Supreme Court, the decision of which was that palm oil must be regarded as an artificial colouring matter, and must pay duty as such, even if used as a material ingredient to improve the wholesomeness and flavour of the product.

=Soya Bean Oil=, expressed in China from the Soya bean, is now coming extensively into use, and is already employed for culinary purposes. It has, according to De Negri and Fabris, the following properties:—

+-----------------+----------------+--------+
|Specific Gravity | Saponification | Iodine |
| at 15° C. | Value. | Value. |
+-----------------+----------------+--------+
| 0·9242 | 191 | 121·3 |
+-----------------+----------------+--------+

The three following are among the more recently discovered oils, and are now sometimes used in the preparation of vegetable butter:—

=Shea Butter.=—This is extracted from the kernels of the Bassia Parkii, grown in Africa and Eastern India. It is somewhat tough and sticky, and has the following properties:—

+---------------+-----------------+--------+------------+
| | Acidity | | Refractive |
|Saponification | (as Oleic Acid) | Titre, | Index at |
| Value. | per cent. | °C. | 60° C. |
+---------------+-----------------+--------+------------+
| 181 | 8·2 | 53·2 | 1·4566 |
+---------------+-----------------+--------+------------+

=Mowrah-Seed Oil.=—This oil, obtained from the seeds of Bassia longifolia and Bassia latifolia, is largely imported into this country from India. It gives the following figures on analysis:—

+---------------+-----------------+--------+------------+
| | Acidity | | Refractive |
|Saponification | (as Oleic Acid) | Titre, | Index at |
| Value. | per cent. | °C. | 60° C. |
+---------------+-----------------+--------+------------+
| 187 | 10 | 43·4 | 1·4518 |
+---------------+-----------------+--------+------------+

=Margosa Oil.=—This is prepared from the seeds of _Melia azedarach_, a tree found in most parts of India and Burmah. According to Lewkowitsch (_Analyst_, 1903, pp. 342-344) it has the following analytical characteristics:—

+----------------+--------+--------+
| Saponification | Iodine | Titre, |
| Value. | Value. | °C. |
+----------------+--------+--------+
| 196 | 69·6 | 42 |
+----------------+--------+--------+

Of the other raw materials mention may be made of milk, which should not contain less than 3 per cent. fat, and may be fresh or “soured”; water, which should be as pure as that of a drinking supply; salt (sodium chloride), which is readily obtainable in a very pure state; and colouring matter, which generally consists of annatto.