This section is from the book "A Treatise On Beverages or The Complete Practical Bottler", by Charles Herman Sulz. Also available from Amazon: A Treatise On Beverages.
The prominence given ginger ale in the list of carbonated beverages, and its wide popularity, renders the subject of ginger a most interesting one. The trade has been accused of many sins in the name of this well-known drug, and a more intimate acquaintance with its history and species cannot fail to be profitable to bottlers.
The ginger plant is reed-like, with annual leafy stems, three to four feet high, the leaves smooth, oblong and tapering toward the extremities, five or six inches in length. The flowers are in cone-shaped spikes borne on other stems thrown up from the root, are yellowish and emit an aromatic odor. Its virtues reside in its root, of which two varieties are found in the market, the black and the white, or Jamaica ginger. The plant is a native of Asia, in the warmer climates of which it is universally cultivated, but not known in a wild state. It has been introduced into most tropical countries, and is now found in the West Indies, South America, tropical Western Africa and Australia.
Ginger is known in two forms, coated and uncoated. The latter, preferred by some few for extracts, etc., is produced by scraping the root, washing and drying in the sun. Thus prepared it has a pale, buff color, breaks easily, showing a mealy fracture with numerous bristle-like fibres.
When cut with a knife a fresh and vigorous specimen of giuger root appears pale yellow, soft and starchy, while an older sample is flinty, hard and resinous. Coated ginger is covered with a wrinkled brown skin or membrane, which imparts to it a somewhat coarse and crude appearance. Internally it is usually of a less bright and delicate hue than ginger from which the bark or rind has been removed. Much of it is dark, horny and resinous.
The varieties found in the market are distinguished as Jamaica, Cochin, and African. The first two are usually. scraped gingers; the last is coated, and is the kind used by spice dealers. The best known in commerce, as before stated, is the unbleached Jamaica ginger, which is uncoated, and occurs in large, bold, fleshy pieces, technically called "races". The inferior sort come in smaller pieces, are darker colored and shriveled. The dealers frequently "dress up" the common dark-colored gingers by washing them in water, drying them and "rouncing" them in a bag with a little whiting or calcined magnesia, called "washed ginger; " or they bleach them by dipping them into a solution of chloride of lime, or by exposing them to the fumes of burning sulphur, called "bleached ginger;" or they dip them into a milk formed of whiting and water, called "white-washed ginger". Powdered commercial ginger, such as is on sale at ordinary drug or grocery stores, is with difficulty obtained pure. The common adulterants are flour, arrow-root, etc. The first may be detected by the microscope, the latter by the flavor. Exhausted ginger, as it comes from the hands of the extract manufacturers, enters as an adulterant into freshly ground ginger; the spice mills especially dispose of a great quantity of exhausted ginger mixed with their genuine goods. Investigations by experts has proved that in powdered form ginger has been adulterated as high as eighty per cent. Of inferior material, naturally, no high-grade beverages can be made.
Cochin ginger is preferred by English manufacturers, while American favor the Jamaica almost exclusively. The former variety is said to be stronger, but the latter gives better results. Large quantities of both African and Jamaica ginger are imported into this country. It is claimed that African ginger has a better flavor, is more uniform and of greater strength than the Jamiaca variety, which is evidently true, and both the African and East Indian are more pungent and aromatic, and therefore preferable for some purposes. Bleached and decorticated or scraped ginger, however, such as Jamaica ginger, has a less harsh taste, is always preferred for bottlers' uses. Besides, the volatile oil from Jamaica ginger is far pleasanter than when obtained from African or Chinese (Cochin ginger), and, moreover, both the other kinds have far more of the resins which we seek to eliminate. The United States Pharmacopoeia recognizes only the uncoated or decorticated variety, that is, Jamaica ginger. In the opinion of chemists, extracts and tinctures should preferably be made from the unpeeled variety. Ginger is a choice stimulant and a pleasant and valuable carminative. In the hands of an experienced bottler, a great variety of beverages are greatly improved by the addition of ginger. As employed by chemists and bottlers for extracts it is first crushed or ground to about the fineness of coarse ground coffee.
Thresh finds in ginger a hot, pungent resin, a secondary less active resin, an active principle (gingerol), a volatile oil, a heavy oil, wax, fat, gum, coloring matters, etc. We wish to save nearly all of these except the first hot resin.
The virtues of the root are usually extracted by alcohol. Ginger is an aromatic stimulant and stomachic, very useful in flatulence and spasms of the stomach and bowels, and in loss of appetite and dyspepsia. In the hands of an experienced chemist or good bottler a large variety of carbonated beverages, beer, wines, and ales are greatly improved by the addition of this flavoring ingredient, which is, perhaps, one of the most wholesome of the aromatic kinds, and is less acrid or harsh than the peppers, for which bottlers seem to have a weakness. Capsicum, or red pepper, unduly excites the coatings of the stomach, while ginger has a soothing effect. For this reason ginger ale, whose base is the genuine article, and not the burning substitutes, enjoys a popularity equaled by no other carbonated beverage.
It is obtained by distilling the crushed ginger roots with water or applying steam under pressure. Depending on the quality of the root it will yield about from one to two and a half per cent, of oil of a pale-yellow color, having the peculiar odor of ginger, but not its pungent taste. It has a specific gravity of 0.880 to 0.900 and boils at 246° 0.
Thresh recognized in ginger the presence of traces of an alkaloid, and named the pungent principle gingerol. It is an odorless fluid, has an extremely pungent taste, soluble in alcohol. Jamiaca ginger yields the smallest, and African ginger the largest, amount of volatile oil, resins and gingerol.