This section is from the book "The Planting, Cultivation And Expression Of Coconuts, Kernels, Cacao And Edible Vegetable Oils And Seeds Of Commerce", by H. Osman Newland. Also available from Amazon: The Planting, Cultivation And Expression Of Coconuts, Kernels, Cacao And Edible Vegetable Oils And Seeds Of Commerce.
Noteworthy among the former are (a) the machines devised by Poisson and constructed by Louis Labarre, of Marseilles ; (b) the mill devised by Hupfeld and constructed by Messrs. Humboldt, of Cologne ; (c) the machine patented by Hawkins.
The most prominent of the second class was, before the war, that of Haake, of Berlin. Other machines have been patented by Buchanan and Tyrell, and by Dyer and Innes-Ward.
Complete plant for the preparation of palm oil in which the pulp is removed from the nuts and then pressed is made by A. F. Craig & Co., Ltd., Paisley, Scotland ; A. Olier et Cie., Argenteuil, France ; and Louis Labarre, Marseilles. The plant constructed by the first-mentioned firm is known as the Caledonia dry plant, and differs in method of working from most of the existing processes in not steaming or boiling the fruit or pulp with water before expression of oil. It is claimed for this process that neither the fruit nor the oil comes in contact with water, so that even if fatty acid and glycerine occur in over-ripe fruit no glycerine is lost. The process of depericarping is effected by a machine patented by H. G. Fairfax (English Pat. 18050/1914).
The oil, after being boiled, yields a pleasant and yellow-coloured fat, which is sometimes eaten and relished by Europeans residing in West Africa. Most of it, however, is exported to Europe and used for various purposes by the soap-maker and the chandler, not to speak of war purposes. Some oil is harder than others, notably that from thin pericarps; the softer oil is of two qualities, (a) Lagos and (b) ordinary soft oil, both of these oils fetching from £3 to £4 per ton more than the harder quality.
Soap-makers and other users of palm oil are now demanding a contract for their requirements, based on purity and on the first grade of oil containing not more than 18 per cent of free fatty acids. Many of the inferior grades will thus become unmarketable, except at a seriously depreciated price.
The softer the oil and the more glycerine therein (which varies in inverse proportion with the acidity) the greater its value.
The chemical and physical constants of the palm oil of commerce are: -
Specific gravity at -
• • •
0.9209 to 0.9245
24° to 42.5° C.
■ • •
196.3 to 205.5
53 to 57.4
0.86 to 1.87
94.2 to 97
Solidifying point of fatty acids varies from 35.8° to 464° C, usually
44.5° to 45.0° C.
The kernels or seeds contained in the nuts or "stones" of the oil palm are obtained by cracking the nuts by hand or by the aid of a nut-cracking machine, after the orange coloured palm oil has been extracted from the outer pulpy portion of the fruit. In Sierra Leone, this is, principally, the work of thousands of small farmers in the Colony and Hinterland, who, with wives and families, work at this industry during the season. Their produce is collected by agents and sub-agents representing the large trading firms.
The kernels are exported, and the expression of the kernel oil carried out in Europe. Palm kernel oil is white in colour and of rather softer consistence than palm oil. The kernel, when it reaches the mills, is treated either by the crushing or chemical extraction processes to obtain this oil. The oil forms about 50 per cent, of its contents, and has a very high commercial value, being sold at about £40 per ton in peace time, and at a much higher figure during war. Formerly employed solely in the manufacture of soap, candles, etc., palm kernel oil has latterly been more and more in demand among the makers of edible products, such as " nut-butter," chocolate fats, etc. Before the great World War, most of our supplies of this oil were imported from the Continent. Now that the question of the people's food supplies has become one of vital moment to the country, the production of large quantities of wholesome nut-butter, sold at almost one-third the price of ordinary butter, and manufactured entirely within our own borders from produce supplied by British Colonies, may be regarded as a factor of no small importance in furthering the national policy by facilitating domestic economy.
Before the war the Germans imported kernels from Liverpool, and then sent the oil back to that port and undersold the Liverpool crushers.
Coconuts, Kernels, etc.- Capt. H. O. Newland.
The Native Preparation of Palm Oil in the Congo.
This was done by Germany putting a heavy tariff of £6 a ton on refined edible oils, importing the palm kernels free, and charging her own manufacturers and countries with whom she had special treaties, an extra price which enabled her to undersell the British market. She also captured the Canadian market, although Liverpool enjoyed exceptionally low freight to Canada. Before the war, also, Britain imported margarine to the extent of 1,518,297 cwts. in 1913, value £3,917,701. Of this amount 1,483,417 cwts. came from Holland. Now Britain is making her own margarine from her own raw material, and as it was being bought retail at from 7d. to Is. per lb., while butter was costing 2s. to 2s. 6d., the gain to the consumer at home is great.
Messrs. Lever now have their own steamers running between West Africa and Liverpool for their trade in kernels and oil. In Sierra Leone alone, the palm kernels exported in 1917 reached the record figure of 58,000 tons.
The following table gives the range of the principal constants of commercial palm kernel oil. The corre-sponding figures for coconut oil are added for comparison :-
Specific gravity 99°/15°,
Iodine value, per cent.,
10.3 to 17.5
8.0 to 10.0
242 to 255
246 to 268
20.0° C. to 25.5° C.
21.2° C. to 25.5° C.
82.4 to 90.5
5.0 to 6.8
6.6 to 7.5
Yield of oil,
46.7 to 52.5
64.5 to 74.7
When the weight of a cask of palm oil is ascertained, and in invoicing the same to the buyer in this country, 16 lbs. per cwt., or one-seventh of the whole, is deducted as representing the weight of the cask.
This is an agreed figure and applies only to such casks as are termed " regular," and comply with a certain measurement. In the case of palm kernels, if these are shipped in bags, the actual weight of the bags is ascertained by trial, and this weight is deducted from the gross weight of the kernels. The usual tare is 13 lbs. for five bags ; when shipped in bulk there is no tare.