Page:The New International Encyclopædia 1st ed. v. 01.djvu/176

This page has been proofread, but needs to be validated.
ADULTERATION.
132
ADULTERATION.


Jellies and Jams are often adulterated with gelatin, glue, and with more or less injurious coloring substances and artificial "fruit oils." The adulteration can be detected only by a careful chemical examination. Considerable quantities of zinc oxide have been found in preserved fruits.

Mustard is seldom sold unadulterated. The common adulterant being flour or some similar farinaceous product, the fraud can usually be detected by means of iodine, which reveals the presence of starch by yielding an intense blue coloration. The microscope, too, is useful in examining mustard.

Pepper, cinnamon, and other spices are adulterated with a variety of substanees, the presence of which can usually be detected by the use of the microscope. Substances passing for pepper have sometimes been found to contain no pepper at all, and to be made up entirely of mustard-husks, powdered capsicum, starch, gypsum, sand, etc.

Beer has been found to contain potash, vitriol, alum, licorice, linseed, tartar, poppy heads, chamomile, pine sprouts, chicory, henbane, wild cherries, picric acid, salicylic acid, etc., some of these substances being more or less injurious to health. The deleterious qualities of poor beer have often been masked by the addition of salicylic acid. The latter substance itself is comparatively harmless, though large amounts of it may be very injurious; its use in Germany has been prohibited by law, mainly because it serves to conceal the properties by which foul beer may otherwise be readily recognized. Arsenic, too, has been found in samples of beer, and in Manchester, England, several deaths have been reported due to beer thus adulterated.

Wines are adulterated with a variety of substances, most of which, it must be observed, are harmless. The addition of such substances as water, alcohol, glycerin, salicylic acid, potato syrup, artificial flavoring substances, natural as well as artificial coloring substances, cream of tartar, gypsum, etc., is extensively practiced. Sugar is often added to the must, so as to increase the amount of alcohol in the resulting wine. The most injurious of these adulterants are salicylic acid (if present in large quantities—as is often the case) and gypsum. Salicylic acid is added so as to prevent the wine from souring. Gypsum is added for the purpose of precipitating out certain organic substances, the presence of which may in time cause the wine to become turbid. The harm done by the addition of gypsum is due to the transformation of this substance into acid potassium sulphate, considerable quantities of which are injurious to health. Natural coloring substances like cochineal, huckleberry juice, cherry juice, etc., are mostly harmless. On the other hand, artificial coal-tar colors like fuchsine and magenta, which are sometimes detected in wine, may be quite injurious to health. The presence of such colors may be suspected if a piece of woolen fabric dipped in the wine is dyed pink, though this may also be effected by the harmless cochineal. Adulteration of wines may be detected by chemical analysis, the principal steps of which consist in determinations of alcohol and of the total acidity, and in an examination of the residue left on evaporating a known quantity of wine.

Spirituous liquors. Whisky, brandy, and rum are sometimes made by entirely artificial processes. Rum, for instance, is made by mixing dilute alcohol with sugar, caramel, and an artificial "rum-ether;" brandy is made not from wine, but by mixing dilute alcohol with caramel and a little syrup, etc. An injurious ingredient often left by careless or unscrupulous manufacturers, in genuine as well as in artificial spirits, is the well known fusel oil. whose presence may be revealed by the peculiar odor observed on evaporating a few drops of impure spirits on the palm of the hand.

Oils and fats. The adulteration of butter has already been noted above. Olive oil is often adulterated with cottonseed oil. sesame oil, ground-nut oil, etc. The presence of these oils may be revealed by two methods: (1) the addition of strong sulphuric acid to a given quantity of oil causes a smaller elevation of temperature in the ease of pure than of adulterated olive oil; (2) the addition of nitric acid to adulterated olive oil produces a distinct coloration, while pure olive oil remains unaffected. With some experience on the part of the operator, these tests are quite reliable.

Vinegar is often adulterated by the addition of water and of cheap mineral acids, like sulphuric or hydrochloric. The fraud may be readily detected chemically.

Pickles and canned articles of food are often found to contain large quantities of preservatives and of metallic salts. Salts may be derived from the metals of the can or of the solder, in which case their presence may be due to criminal carelessness. Sometimes, however, metallic salts are added by traders on purpose; green copper salts, for instance, are often found in French peas and in pickles, to which they are added for the purpose of improving their color. The presence of salts and of preservatives may be detected by chemical analysis. It may also be mentioned here that careless canning may result in putrefaction and the formation of highly poisonous organic substances, for the effects of which the manufacturers must be considered responsible.

Drugs are sometimes adulterated by the addition of substances resembling the genuine articles in outward appearance but having none of their valuable physiological effects. The practice can not be denounced too strongly or punished too severely. The fraud can usually be detected only by careful chemical examination.

Tobacco is often adulterated with artificial coloring substances and fruit oils, the presence of which may be detected by analysis and is often revealed by the aroma. Snuff is often found to contain considerable amounts of lime and of lead chromate.

Colors and dyes are often adulterated with cheap coloring substances. The fraud can be detected by a careful expert examination.

Textile fabrics are often found adulterated with cheap fibres, with salts, and with excessive amounts of coloring substances. The true value of a fabric can be revealed by chemical analysis. Supposing a given fabric to consist of silk, wool, and cotton, the following facts are taken advantage of for the purpose of analysis: The coloring matter of fabrics is soluble in boiling dilute hydrochloric acid; silk fibre is soluble in a boiling solution of basic chloride of zinc; wool is soluble in a solution of caustic soda; cotton fibre is practically insoluble in these reagents. Evidently, by treating the given fabric sueces-