This section is from the book "Practical Dietetics With Special Reference To Diet In Disease", by William Gilman Thompson. Also available from Amazon: Practical Dietetics with Special Reference to Diet in Disease.
American whiskies are classed as (1) rye and (2) Bourbon, from the county of that name in Kentucky.
The proportion of materials used in making the "mash" for distillation is, on the average, cornmeal 0.8, rye 0.1, and malt 0.1 (Leoser). This mixture is placed in tubs, and scalded with "slop," the refuse from former distillation. After cooling, it is raked, or mixed by a stick called a "masher." Water is added, and the mass ferments for two or three days.
Sweet mash is scalded with water instead of slops, and yeast is added to induce fermentation.
Sour-mash whisky is made without yeast but with slop. The wort is then heated by steam, and the low wines, called "singlings," are run off from the residue or slop and redistilled, and the whisky is ready for barrelling (Leoser). It should then be kept from three to five years to ripen, according to the details of its manufacture.
Pure rye whisky is distilled by an identical process, but the corn is wholly replaced by rye.
Scotch and Irish whiskies are distilled from a barley mash.
American whiskies are kept in charred barrels, and grow darker from colour derived from the wood (Witthaus). Scotch whisky derives its colour from lying in old sherry casks.
Proof whisky contains equal parts of absolute alcohol and water.
Leoser says: "The difference in quality in different kinds of whisky is infinitesimal, and for therapeutic processes may be neglected, provided the taste of the patient is consulted".
The evil effects of poor whisky are largely due to the presence in excess of a regular constituent, an aldehyde called furfural.
Gin is distilled from rye mash, and flavoured by immersing a bag of juniper berries in the vat towards the completion of distillation.
It is variously known under the names Geneva, Hollands, and Schiedam, the two latter referring to its Dutch source, the former being derived from the French word for juniper, genièvre, of which gin is a corruption (Pavy). Gin may contain 17 per cent of alcohol, but it is often diluted, and when sweetened besides, it is known as "Old Tom".
Rum is distilled from a mash of molasses. The wort contains about 15 per cent of sugar, and the fermentation process requires from nine to fifteen days. Rum was formerly made in New England, but it now comes chiefly from the West Indies, and that made in Jamaica is considered the best. Other rum is made from rectified proof spirit. It is a liquor which improves very much on keeping for several years. The flavour of rum, which is principally due to butyric ether, is produced by adding molasses, caramel, and sometimes fruits, such as pineapple or guava. Acetic and other ethers are also present.