Popular Science Monthly/Volume 30/November 1886/Trade Distinctions in Alcoholic Liquors
THE answer given by Mr. Dawson to the question, "Can pure, un-adulterated alcoholic liquors be now obtained?" supposed to be vicariously asked by an inquiring public in his article, "How Alcoholic Liquors are made," in the May issue of "The Popular Science Monthly," would have been entirely correct if it had ended with a simple affirmation. As it stands, however, it is grossly misleading, inasmuch as it confounds substances possessing essentially different characteristics, which are universally recognized commercially by distinctive nomenclatures, and under the United States internal revenue system are controlled by different laws and regulations.
After giving a brief outline of the processes of mashing, fermentation, and distillation, which is in the main correct so far as it goes, Mr. Dawson says: "The process of rectification is generally done by re-distilling, or filtering through alternate layers of woolen blankets, sand,, and granulated charcoal, . . . after which process a little burnt sugar is added to give them a kind of straw-color, simply, I presume, to distinguish them from water. . . . After rectification, the spirits are gauged by the United States gauger, and a rectifier's stamp is placed upon each package, and the whisky is then ready for market, pure and unadulterated, and known as one-stamp goods. Remember that I am now stating how good whisky is made. . . . Therefore, if you want a pure article, purchase from a distiller or first class reliable dealer. . . . Insist that the spirit must be at least twelve months old." Merely remarking that spirits to which burnt sugar has been added would not ordinarily be called pure and unadulterated, or the addition be considered necessary to distinguish between two such dissimilar substances as alcoholic spirit and water, I make the unqualified assertion that what is above described as good whisky is not whisky at all, and never can be. This will become plain upon a consideration of some of the distinctive details in the production of rectified spirit and whisky, by which it will appear that, although the molecular changes by which starch is converted into glucose, and glucose into spirit, are the same in both cases, the subsequent treatment differs widely, with a corresponding dissimilarity in the finished product.
It is well known that in the chemical transformations which take place during alcoholic fermentation, besides ethyl or ordinary alcohol, which is the chief remaining product, certain other substances are generated which are collectively known as fusel-oil, and which may be defined as "those products of alcoholic fermentation which distill at a higher temperature than ethyl alcohol" (173° Fahr.). The principal of these is always amyl alcohol, which boils at 273° Fahr. Besides this there are butylic and propylic alcohols and volatile fatty acids, principally acetic, in variable but subordinate quantities. The fusel-oil has a pungent odor and burning taste, easily detected in the crude product of ordinary distillation. The object of the rectifier is to remove it entirely, and produce what is known commercially as "neutral" or "pure" spirit, his ideally perfect result being ethyl alcohol, chemically pure save for the water of association. It follows, therefore, that all rectified spirit being of the same character, and with a standard of quality, is a staple article of merchandise, and the great consideration with the manufacturer is to produce it with as little expense as possible, rectification being depended on to remove all offensive ingredients.
Damaged grain, which can be bought so cheaply that the low price will compensate for decreased yield and increased expense of handling, is as available as any other, provided that rectification will rectify the product. Even potatoes, which produce in fermentation such an excessive quantity of fusel-oil that amyl alcohol is commonly known as "potato-oil," are, on account of cheapness, extensively used in Germany, and so perfectly is the rectification conducted that the German pure or "Cologne" spirit is unsurpassed in quality.
When amylaceous material is boiled with a small proportion of a strong mineral acid, there results an almost perfect conversion of the starch into sugar. For this reason an attempt was made in this country several years ago, on a commercial scale, to dispense with the use of malt in the manufacture of rectified spirit by substituting sulphuric acid in the mash, and afterward neutralizing it before fermentation. Had the attempt been successful, it would, on account of the cheapness of the substitute, have caused a material reduction in the cost of the alcoholic product. It turned out, however, that the successful neutralization of the acid was difficult, and that the alcohol developed by the subsequent fermentation was so acted upon by it as to produce sulphuric ether, which, besides causing a waste of material, could not be removed economically; had this proved feasible, sulphuric acid would undoubtedly have come into general use in the manufacture of rectified spirit.
In every detail of the manufacture the same law of economy holds good; and that machinery is most popular which will accomplish the desired result with the least expenditure of time, material, fuel, and labor.
I mention these facts mainly to show that, however unpromising for a favorable result are the preliminary materials and means, rectification thoroughly conducted is relied upon as a practical remedy for all defects, and they no more detract from the character of the finished product than does the nature of its source from the purity of perfectly filtered water.
Pure or neutral spirit is largely used for the manufacture of counterfeit whisky, brandy, etc., in which the imitation is produced by the addition of foreign substances which must be used sparingly, both on account of economy, and because their character must not be too obtrusively shown. It is plain, therefore, that the more effectively the pungent fusel-oil is removed, the better the rectified spirit will be for the purpose, as any attempt to mask its odor and taste by an excess of the flavoring materials would betray the deception by the character of the resulting products. Mr.Dawson truly says that "compounding is diabolizing," but rectification is necessarily its preliminary step.
Besides the fusel-oil, rectification also removes the essential oils which may be contained in the alcoholic distillate, naturally giving it the characteristic flavor of the original grain, rye imparting a rye-flavor, corn a corn-flavor, etc. While there is nothing necessarily injurious in these essential oils, they would nevertheless be justly considered impurities where the object in view is the production of neutral spirit, and are naturally eliminated by the mechanical means employed for rectification.
Our finished product is now as complete as it ever can be, as ethyl alcohol possesses inherently no latent quality which can develop in it a more perfect character. Even if the unusual device is adopted of storing it in a charred-oak barrel (a treatment almost universal with whisky), the resulting color and astringency will add nothing to its value, but a marked and rapidly increasing shrinkage of volume will follow, without any compensating advantage. It behooves the owner, therefore, to market it as soon as possible, and it would certainly be some especial reason which could induce him to keep it on hand for even the shortest time (twelve months) which Mr.Dawson regards as necessary for its proper development. Rectified spirit, therefore, may be described as the purified product of crude alcoholic distillation (high-wines), and as close an approximation to pure ethyl alcohol and its water of association as the mechanical means available to the rectifier will produce.
The legal definition goes still further, and includes, in the words of the statute, "any spurious, imitation, or compound liquors" manufactured by mixing distilled spirits, wine, or other liquor, with any materials for sale under the name of whisky, brandy, rum, etc. All rectified and compounded goods put up in casks are, under Government regulations, stamped with one stamp only, and are known as "one-stamp" goods.
What, then, is whisky, and especially good whisky?
Its largest proportion is of course ethyl alcohol and water, with sufficient of the essential oil of the grain to give it its distinctive grain-flavor, although this is sometimes so feebly developed as to leave its character in doubt, and deteriorate from its market value, especially in the case of rye-whisky. When new, it also necessarily contains a small quantity of fusel-oil, and it is this complex substance which gives to whisky its distinctive character as compared with other alcoholic liquors, and, by the relative proportions of its component parts to each other and to the whole mass, eventually determines its quality. In view of the poisonous and deleterious character of fusel-oil, this statement may seem like a confirmation of the frequently expressed opinion that all whisky is essentially injurious in its physiological effect; and, indeed, the fact of its presence in immature whisky has been illogically used as one of the strongest reasons in favor of total abstinence. The argument, however, is no more consistent than would be the indiscriminate condemnation of all fruit because unripe fruit is unwholesome, and a large proportion of it never reaches maturity at all. For note the proviso, "when new." ... Whisky, when first distilled, is entirely colorless, and, with a few local exceptions, is put up in charred white-oak barrels. The gradually deepening amber hue is imparted to it by the thin brown layer of baked wood underlying the charred surface, the charcoal itself—contrary to the general opinion—having no influence in this respect. No extraneous coloring-matter is needed, nor is any ever used by first-class distillers. A very little tannic acid is also extracted from the wood, causing a slight astringency in the liquor. By far the most important changes, however, are the chemical ones which take place in consequence of the presence of the fusel-oil, its constituent acids and alcohols acting and reacting upon each other with the production of fragrant ethers at the expense of the crude re-agents, so that, in a perfectly ripened whisky, the fusel-oil should disappear, with the formation of acetate of amyl (pear-oil), butyric ether (pineapple essence), valerianate of amyl (apple-oil), œnanthic ether (Hungarian-wine oil), etc. Strange transformations these may seem at first sight; but, nevertheless, they are entirely in accordance with chemical analogy, and by no means so remarkable or complex as those by which the volatile alcohol is derived from the solid starch. The development of these fruit-essences is very slow, but may be somewhat hastened by good ventilation and the proper degree of natural heat. It is probable that there are also other subtile changes, the rationale of which has never been explained, but without which the result would be imperfect, as otherwise it would be fair to suppose that the same end could be attained by adding the proper fruit-essences to rectified spirit, whereas in fact the art of the compounder has never been able to produce a good commercial imitation of the genuine article.
The entire series of changes is called "aging," and to it is due the mellowness and aroma which characterize a well-ripened maturity. They can never take place in rectified spirit, as it does not contain the necessary constituents. The length of time during which good whisky will continue to improve can not be limited by any absolute number of years. It should, however, never be used when younger than from three to five years; six years old is still better, and under wise Government regulations it might come about that the usual age will not be less than that.
Too much fusel-oil is even more destructive of quality than none at all, and produces a crudeness and roughness which no lapse of time can remove. There is plenty of whisky made with just these characteristics, but not even by courtesy can it be called good; some of it, indeed, is so bad that, after a very limited time, it grows worse instead of better; such a result can come only from the carelessness or incompetence of the manufacturer, or from lack of suitable apparatus.
The great aim of the intelligent distiller is, first, to prevent excessive development of fusel-oil; and, secondly, to so arrange the details of his distillation that just the proper quantity shall appear in his distillate, and in the proper proportions. Theoretically its constituents should be possible of removal from the ethyl alcohol by ordinary distillation, in consequence of their higher boiling-points. In fact, however, certain portions are carried over mechanically at lower temperatures, and it is this fact which makes it possible, by the shape, arrangement, and manipulation of the distilling apparatus, to so control the process that, practically, none of the constituents of the fusel-oil shall be in injurious excess or deficiency, but all harmoniously proportioned to further the development of the aging-process. This partial control, however, does not relieve the fine-whisky distiller from the necessity of close attention to the preliminary steps. Good grain is absolutely necessary for the production of good whisky. Good water, scrupulous attention to cleanliness, and the most careful personal supervision, guided by long experience, are equally imperative; for, unlike the rectifier, he has no universal remedy after distillation for all defects. His product, once imperfect, must either remain so, or, by rectification, lose its character altogether.
Mr.Dawson says, either directly or by implication, that most good whisky-distillers either rectify their product themselves or that it is done in a rectifying-house. Such a gross mistake could only come from want of discrimination between the distinctive characteristics of fine whisky and rectified spirit, the former being either excluded entirely from his consideration, or else confounded with the lower grade of goods. As a matter of fact, no fine whisky is ever rectified, and from the previous description it is easily seen why such treatment is not only unnecessary, but would be positively destructive to its proper development. Neither is it ever offered for sale as one-stamp goods; why, will be easily understood when it is known that the best brands of fine whisky are worth, when new and in bond, from two to three times as much as one-stamp or rectified goods, the disparity in value increasing with age.
Explanation of the cause removes the mystery; and to the judgment of the reader, in view of the facts set forth, I leave the consideration of the propriety of using one-stamp alcoholic spirit twelve months old.