Chapter VI: Margarine and Other Butter Substitutes

Margarine, Oleomargarine, or Artificial Butter—Invention
and Development—Modern Processes and Formulæ—Vegetable
Butter.

It has already been pointed out in Chapter I. how essential in all except very hot countries is a fair proportion of fat in the human diet, and, prior to the introduction of artificial butter, this could only be largely made up among the poorer classes of the community by the use of “dripping,” the price of genuine butter being prohibitive. Realising the importance of the subject, the French Government in 1869 offered a prize for the discovery of an artificial substitute for butter, which should not only be cheaper, but also remain free from rancidity for a longer period than butter. This led M. Mège-Mouries, a French chemist, to investigate the whole question of the formation of fat in milk, and he was successful in securing the prize. Physiological experiments soon led him to the conclusion that in the series of transformations by which the butter fat is produced in the animal economy, the carbohydrate matter consumed by the animal is first converted into fat, and this in turn, after being deprived of much of the stearin it contains, by respiratory combustion, is changed by the digestive action of pepsin into butter fat, and a method was devised for effecting this latter process artificially.

The original plan adopted by M. Mège-Mouries was to take 1000 kilos of fresh beef fat, preferably from the kidney or intestines, and after thoroughly comminuting it and freeing it from tissue, to warm it at 45° C. with 300 kilos of water, 1 kilo of carbonate of soda, and two sheep’s or pigs’ stomachs for two hours, when, under the action of the pepsin, the fat separated completely from any remaining tissue, and came to the surface as a homogeneous fluid. This was then decanted into a second vessel warmed to 45° C., and washed with a 2 per cent. solution of common salt, which prevented any fermentation. After allowing it to stand, a limpid yellow fat separated, having a butter-like odour, and on cooling to 20-25° C., this crystallised to a semi-solid mass, with a granular structure which, when the fat was cut in thicknesses of half an inch, wrapped in linen cloths, and subjected to a moderate hydraulic pressure between hot plates, at a temperature of 25° C., allowed 50 to 60 per cent. of a soft fat, comparatively free from stearin, to be expressed.

This fluid fat, or “oleomargarine,” as it was called, solidified on cooling, and constitutes what was originally sold in Paris under the name of “Margarine.”

This soft fat was next converted by Mège-Mouries into a product more closely resembling natural butter by churning it for two hours with 10 per cent. of cow’s milk, and water in which was macerated 0·4 per cent. of cow’s udder, complete emulsification being effected by the action of the pepsin and the churning. After washing with cold water, salting, colouring with annatto, and finishing off as with ordinary butter, a very good imitation of the natural article was obtained.

According to Boudet, this artificial butter has a melting-point of 17 to 20° C., contains about 12·5 per cent. of water, and, in the dry state, 1·20 per cent. of insoluble casein, and is less liable to become rancid than natural tallow.

Factories were soon erected at Poissy and at Liesing, near Vienna, to work the process, which was patented by Hippolyte Mège-Mouries, in England, in 1873. The English patent claimed a process for preparing artificial butter by mixing the oleomargarine with water containing sodium bicarbonate, casein, and mammary tissue. The sale of artificial butter was authorised by the Council of Hygiene of Paris in 1872, the use of the name “butter” to describe it being prohibited.

The name “margarine” was first applied by Chevreul to what was at that time considered to be a definite single compound of margaric acid with glycerin, and found in human fat and olive oil. Subsequent research by Heinz has shown, however, that so-called margaric acid is in reality a mixture of stearic and palmitic acids, and the term “margarine” does not therefore represent any definite chemical body. The name “oleomargarine” was introduced to signify what was believed to be a mixture of olein and margarine from which the stearin had been separated. Part of the “margarine” is now known to consist of stearin and palmitin, so that the oleomargarine still contains these two glycerides, though to a much smaller extent than in the original beef or mutton fat. The softer fat, from which the stearin has been removed, is known in America as “oleo oil,” the artificial butter made therefrom being termed “oleomargarine.” In this country it was decreed by the Margarine Act of 1887 that all artificial butter should be sold under the name of “margarine,” and this has long since become a well-established, popular name, such terms as “butterine,” and “Dutch butter,” which had gradually come into use, being declared illegal by this Act.

The successful working of the Mège-Mouries process quickly led a number of other investigators to take up the subject of the production of artificial butter, and the next few years following were prolific in patents for the purpose.

Among many others, Lake, in 1871, patented the admixture of cotton-seed oil; E. G. Brewer, in 1874, the churning of treated tallow with 3 to 4 per cent. of sour milk and 2 per cent. of oil; and Pitt, in 1877, the addition of arachis oil; Mège the same year obtaining a further patent for the use of an artificial gastric juice, consisting of hydrochloric acid and acid phosphate of lime, to help in the artificial digestion of the fat.

In spite of these, the method of margarine manufacture does not appear to have undergone much change, and is to-day in most respects closely similar to that originally proposed by Mège, with the exception that the artificial digestion of the fat is now dispensed with, and a certain proportion of vegetable oils is generally added.

In this country the oleomargarine, or basis of artificial butter, consists usually of the softer portion of tallow or “premier jus,” but in America a very large part of this, which after further treatment is there known as “oleo oil,” is replaced by “neutral lard” obtained from the perfectly fresh leaf, or kidney and bowel, fat of the pig. The preparation of the “neutral lard” is almost identical with that adopted for tallow, and as the latter is invariably employed in this country, the modern preparation of margarine with this as a basis will now be described.

=Modern Process.=—The carefully selected caul fat of freshly slain oxen is first washed in a vat with warm water to remove blood and tissue, then hardened by chilling with ice water, and thoroughly comminuted by passage through rollers or cutting machines. It is next transferred to tin-lined and steam-jacketed vessels, in which it is raised to a temperature of about 40 to 45° C., when the softer portions of the tallow melt and rise to the surface, the separation being facilitated by sprinkling salt over the surface.

This clear oil, which is known as “premier jus,” is then siphoned off into a second series of steam-jacketed vessels, in which it is raised to about 45° C., after which more salt is added, and a further settling takes place. The clear, super-natant oil is next transferred to shallow wooden vats, in which it is allowed to stand for three to five days at a temperature not exceeding 20° C., in order to crystallise out the stearin, after which it is thoroughly mixed, wrapped in canvas cloths, and subjected to pressure, whereby the soft “oleo oil,” or oleomargarine, is separated from the harder stearin or oleo-stearin, which is used in the manufacture of lard substitutes, or sometimes in margarine in place of part of the oleomargarine, when a large quantity of vegetable oils has been employed.

The oleo oil is then removed to churns, in which it is mixed with “neutral lard,” cotton-seed oil, olive oil, sesame oil, maize oil, or other vegetable oil, and milk (fresh or sour) or cream, or sometimes water, a certain proportion of butter being frequently added to impart a better flavour to the margarine.

The churning is frequently carried out in special vessels fitted with internal agitators, and a novel form of these has been patented by Schroeder (Eng. Pat. 25,404, 1905), in which the blades rotating at a high speed gradually convert the ingredients into a cohesive and homogeneous emulsion, which is forced out at the bottom of the vessel.

After churning until completely emulsified, the mixed fat is drawn off into tubs containing pounded ice, which cool it rapidly and so prevent crystallisation. It is then coloured with annatto or other colouring matter, and after salting if desired, is finished off in the same way as ordinary butter.

The number of materials available renders a very large variety of combinations possible, and, naturally, successful formulæ used by private firms are kept secret. The following formulæ were published, however, by the United States Census Report for 1900:—

CHEAP GRADE.

Oleo oil 495 parts
Neutral lard 265 ”
Cotton-seed oil 315 ”
Milk 255 ”
Salt 120 ”
Colouring matter 1¼ ”

which is sufficient to produce 1265 to 1300 parts.

MEDIUM HIGH GRADE.

Oleo oil 315 parts
Neutral lard 500 ”
Cotton-seed oil 280 ”
Milk 280 ”
Salt 120 ”
Colouring matter 1½ ”

producing 1050 to 1080 parts.

HIGH GRADE.

Oleo oil 100 parts
Neutral lard 130 ”
Butter 95 ”
Salt 32 ”
Colouring matter ½ ”

producing about 325 parts.

Such a formula as this would not be permissible in this country, where the maximum addition of butter to margarine is fixed by law at 10 per cent., and the neutral lard is more usually replaced over here by oleomargarine or “oleo oil,” a suitable formula being as follows:—

Oleomargarine 230 parts
Cotton-seed oil 40 ”
Olive oil 20 ”
Butter 30 ”
Salt 32 ”
Colouring matter ½ ”

The proportion of cotton-seed oil should not, speaking generally, exceed more than about 25 per cent., or its characteristic flavour becomes apparent. Besides cotton-seed and olive oils, arachis, palm nut, and cocoanut oils now enter frequently into the composition of margarine, and in Germany the use of sesame oil to the extent of 10 per cent. has been compulsory since 1897. Palm oil, which imparts a yellow tint to the margarine, is also occasionally incorporated. This being a firm fat enables the proportion of animal fat to be reduced.

The colouring matter usually employed is annatto, but turmeric and saffron are also occasionally used. The use of mineral colours is most objectionable, and coal tar colouring matters are to be discouraged, though azo dyes are occasionally met with.

Glycerin is sometimes added to margarine to impart a glossy appearance, and sugar or glucose to sweeten it or improve its texture, though this is said to injure its keeping qualities.

Many methods have been devised for causing margarine to froth and become brown when heated, as does genuine butter. The addition of a fair proportion of butter will, of course, secure this, but in the absence of butter it may be accomplished by adding a sufficient quantity of milk. The introduction of casein, lecithin, or cholesterol has been suggested for the purpose, and Fendler has patented the use of 0·5 per cent. of egg yolk, subsequent patentees claiming the preliminary emulsification of the egg yolk with salt solution, lactic acid, etc. Mitscherlich has recently patented the addition of meat extract or yeast.

Though not really necessary in a properly made margarine, various artificial flavourings are occasionally added, ostensibly to render the flavour more similar to that of genuine butter, but more probably, in many cases, to enable a proportion of the margarine to be used in the adulteration of butter without detection by the usual chemical methods. Such flavouring materials include butyric acid or other volatile fatty acid, and certain butyrates, these being dissolved in glycerin or oil, and added in this way to the margarine. Coumarin is also said to be used, and H. A. Snelling recently patented the addition of banana fruit or banana essence.

=Vegetable Butter.=—During the last few years a number of products have appeared on the market under the names of “Vegetable Butter” or “Nut Butter.” These consist chiefly of carefully refined and deodorised cocoanut oil and palm-kernel oil, materials which have lately been supplemented by the addition of margosa oil, shea butter, and mowrah-seed oil. Any suitable mixture of these may be churned with milk, coloured, and salted, and finished off like genuine butter.

=Palm Oil.=—Palm-kernel oil has long been utilised as an edible fat, but hitherto all attempts to make use of any considerable quantity of the fat from the pulp of the fruit (palm oil) have proved unsuccessful.

This is not on account of the deep orange colour of the fat, which could be readily removed by oxidation, but owing to the high proportion of free fatty acids.

The cause of this drawback has been shown by Fickendey (_Der Tropenpflanzer_, 1910, xiv. 566) to be due to the presence of an enzyme in the fresh fruit. For instance, the fat extracted from perfectly fresh fruit had an acid value of 94·5-116, which became still higher if the fruit was allowed to stand for twenty-four hours before the extraction of the fat.

By heating the fruit this enzyme is destroyed, and the fat will then show a low acid value. Thus in four instances in which this was done the acid value did not exceed 5·3.

Fickendey concludes from these experiments that it would be quite possible to put a palm oil of good quality upon the market, provided that the following conditions were observed:—(1) Expression of fresh, completely ripe fruit; (2) destruction of the enzyme by boiling; (3) rapid treatment of the fruit. The last condition is essential, owing to the readiness with which micro-organisms will decompose the fat in the heated fruit.