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ADULTERATION
  


portion, the cream, may prepare a legitimate article of food from the remainder, while he who to that remainder adds something to replace the fat does an illegitimate act, but it must be taken into consideration that the replacement is frequently made with fraudulent intent and that the ordinary purchaser cannot by taste or smell distinguish the adulterated from the genuine article, while there is no difficulty in recognizing skim-milk cheese.

Lard.—Between the years 1880 and 1890 a gigantic fraudulent trade in adulterated lard was carried on from the United States. A great proportion of the American lard imported into England was found to consist of a mixture of more or less real lard with cotton-seed oil and beef-stearine. Cotton-seed oil is one of the cheapest vegetable oils fit for human consumption, beef-stearine the hard residue obtained in the manufacture of oleo-margarine after the more fluid fat has been pressed from the beef fat. These mixtures were made so skilfully by large Chicago manufacturers that for some years they escaped detection. A bill introduced in 1888 into the American Senate to stop this imposture directed general attention to the subject, and energetic measures, taken both in America and in England, quickly put an end to it. From the memorial presented in the United States Senate in support of the bill, it appeared that in about 1887 the annual production of lard in the States was estimated at 600 million pounds, of which more than 35% was adulterated. Compounds were made containing only a small quantity of lard or none at all, yet were sold as “choice refined lard” or under other eulogistic names. Many lard substitutes, chiefly made from cotton-seed oil, are still met with, but are mostly sold in a legitimate manner. From the germ of maize—which must be separated from the starchy portion of the seed before the latter can be manufactured into glucose—the oil (maize-oil) is expressed, and this now is used as a lard adulterant, its detection being far more difficult than that of cotton-seed oil.

Oils.—For very many years all oils were considered to be composed of olein, that is to say, the triglyceride of oleic acid, with small quantities of impurities; chemists, therefore, to distinguish oils of various origin, confined themselves to tests for these impurities, employing so-called colour reactions based upon the change of colour of the oil by various reagents such as sulphuric, nitric or phosphoric acids. These reactions were exceedingly indefinite and unsatisfactory and oil adulteration was prevalent and almost undiscoverable. It has been found, however, that the old ideas concerning the believed uniformity in the nature and constitution of oils were erroneous. Some oils, indeed, do consist of olein, almond oil being a type, others contain a glyceride of an acid which is distinguished from oleic acid by containing one molecule less hydrogen, called linoleic acid. To this class belong cotton-seed and sesame oils. Others again include a glyceride of an acid containing still less hydrogen, linolenic acid (linseed and similar drying oils), and lastly the liver oils are still poorer in hydrogen. These various acids or the oils contained in them combine with various percentages of iodine, oleic acid absorbing the smallest proportion (about 80%); For each oil the iodine absorption is a fairly constant quantity; this number, together with the determination of the amount of caustic alkali needed for complete saponification, the thermal rise with strong sulphuric acid or with bromine, the refraction of light and the specific gravity, now enable the analyst to form a fair idea of the nature of any sample under examination, and, in consequence of this advance in knowledge, adulteration of oils has much declined. The most common adulterant of the more valuable oils, like olive oil, is cotton-seed oil. The oils expressed from the sesame seed or the earth-nut (arachis oil) are also frequently admixed with olive oil. Almond oil is adulterated with the closely allied oils from the peach-kernel or the pine-seed. Deodorized paraffin hydrocarbons also enter sometimes as adulterants into edible oils. There is, however, a marked improvement in the purity of oils generally.

Flour and bread as sold in England are almost invariably genuine. The old forms of adulteration, such as the use of alum for the production of a white but indigestible loaf from bad flour, have disappeared. The only admixture which has been met with during recent years is maize-meal in American produce. This is of inferior food value to wheat-meal.

Sugar in its various forms can hardly be said to be subject to adulteration by the addition of inferior substitutes. One single case of such substitution analogous to the proverbial but probably mythical sanding of sugar occurred between 1880 and 1905 in England, some crushed marble having been found in a consignment of German sugar in a large British establishment. There have, however, been numerous prosecutions for a fraud of another class, namely, the substitution of dyed beetroot sugar for Demerara sugar. Formerly the sugar produced by the old imperfect and wasteful methods of manufacture was more or less yellow or brown from adhering molasses. Sugar, as now obtained, be it from cane or beet, is white; yet the public is so wedded to its customs that white sugar except as lump or castor sugar does not find a ready sale. The manufacturer is obliged to colour his product yellow by artificial means, that is to say, either by the addition of a little aniline dye, harmless in itself, or, as in the West Indies, mostly by the use of a small quantity of chloride of tin, so-called “bloomer.” European refined beet-sugar coloured with aniline dye to distinguish it from Demerara cane sugar is sold under the name of “yellow crystals.” These, although richer in real sugar than Demerara, are without the delicious aroma of cane syrup which belongs to the latter, and are not infrequently fraudulently substituted for Demerara.

Marmalade and Jams.—In the preparation of marmalade and jams, which articles were for a long time made from fruit and sugar only, a part of the sugar, from 10 to 15%, is often now replaced by starch glucose. This material, consisting mainly of a mixture of dextrose and dextrin, is of much less sweetening power than ordinary sugar and mostly cheaper. It is said to prevent the crystallization which frequently used to occur in some jams. The use of glucose has been declared by the High Court (Smith v. Wisden, 1901) to be legitimate, the court holding that as there was no recognized standard for the composition of marmalade the addition of saccharine material not injurious to health could not constitute an offence. Artificial colouring matters and chemical preservatives are almost constant ingredients of jams. To such fruits which, when boiled with sugar, do not readily yield a jelly (strawberries, raspberries) an addition of apple juice is frequently made in the manufacture of jam, without much objection; the pulp of the apple, however, is sometimes bodily added as an adulterant.

Tea.—In consequence of the proviso contained in the Food Act of 1875 that tea was to be examined by the Customs on importation, such tea as was found to be admixed with other substance or exhausted tea being refused entry into England, the adulteration of tea has been virtually suppressed. Great numbers of samples are annually examined by the Customs, and a not inconsiderable proportion of these are condemned because they are either damaged or dirty, their use for the manufacture of theine being permitted, only sound and genuine tea coming to the British public. The practice, very common a generation ago, of artificially colouring tea green with, a mixture of Prussian blue and turmeric, has quite vanished with the decline of the consumption of green tea.

Coffee.—A few cases of artificially manufactured coffee berries, made from flour and chicory, have been observed, but it would not be fair to speak of a practice of adulteration regarding coffee berries. Not infrequently coffee is roasted with the addition of some fatty matter or paraffin or sugar, to give to the roasted coffee a glossy appearance. These additions as a rule are small in amount. Ground coffee is often sold adulterated with chicory, sugar or caramel. Other adulterations, reference to which is found in literature relating to the second half of the 19th century, do not seem now to occur.

Cocoa and chocolate are liable to a number of fraudulent or questionable additions. In the cheaper qualities of cocoa-powder sugar and starch—the latter in the form of sago flour or arrowroot—are admixed in very large proportions, and, in order to give to such mixtures something like the appearance of genuine