Philip Schidrowitz

“ Fermentation is carried on until practically all the saccharine matter is converted into alcohol; and when this is the case, the gravity of the mash is about equal to, or even a little below, that of water. In malt whisky distilleries the original gravity of the wort is usually from 1.050 to 1.060, occasionally lower, but in grain and potato distilleries the worts are often made up to a higher gravity. In Germany gravities as high as 1.11 are employed; but in that country "thick" mashes, owing to the method employed to raise the duty, are a matter of necessity rather than of choice. ”

“ Coming next to the methods ordinarily or frequently employed by distillers for eliminating the undesirable by-products, which, despite all care, are formed in the course of manufacture, the most important undoubtedly is purification by rational fractional distillation. By properly regulating the distilling heats, by using a well-devised still, both in the first instance and also for rectifying, a product very free from fusel oil, and especially from fatty aldehydes and volatile ethers, may be obtained. ”

“ The older methods at the disposal of the distiller have of late years been enriched by the discovery that certain micro-organisms (or rather the enzymes contained in them) possess the power of converting starch into sugar, and also of splitting up saccharine materials into the ordinary products of alcoholic fermentation. It is possible to inoculate a sterilized wort with a pure culture of a micro-organism of this description and subsequently with a pure culture of yeast, and so to avoid all undesirable features of the older processes. ”

“ To convert starchy matter into alcohol is a much more complicated matter. To the operations necessary for the transformation of sugar into spirit, must, in the case of starchy materials, be added that of converting the starch into sugar. ”

“ A distillery must not, without permission, be carried on at a greater distance than half a mile from a market town, nor may it be situated within a quarter of a mile from a rectifying establishment. A distiller must give notice of the erection of new plant or apparatus, of the time of brewing, of the removing of sugar from store or of yeast from wort or wash, of the making of " bub," of the locking of the spirit receiver supply pipe, &c. ”

“ The spirit produced in the United Kingdom is made almost exclusively from malt, unmalted grain (chiefly maize, rye, barley, wheat and oats) and molasses. The relative proportion of malt to unmalted grain has shown a slight tendency to increase during the past twenty years, but the quantity of molasses employed has increased very largely in the same period, owing mainly to the fact that home-made spirit has largely displaced the foreign article for several industrial purposes and particularly for methylation. ”

“ The fusel oil of British pot-still spirits is chiefly composed of amyl and butyl alcohols, whereas in patent spirits propyl alcohol preponderates, that is, in the finished or fine spirit, since the fusel oil separated from patent spirit in the course of distillation consists mainly of amyl and butyl alcohols. Broadly speaking, the higher alcohols present in pot are of higher molecular weight than those in patent spirits. Potato fusel contains a high proportion of isobutyl alcohol, grain fusel of n-butyl alcohol. ”

“ New friends are like new wine: when it is old, thou shalt drink it with pleasure." There is little doubt that the beneficial effect of age on the character of spirits is due to the changes effected in the character and quantity of the by-products, but the exact nature of these changes is by no means clear. ”

“ The type of cask exercises a marked influence on the course of maturation; and, as regards whisky, spirit stored in a sherry cask undoubtedly matures more quickly than that contained in a plain wood cask. The relative humidity of the cellar in which spirit is stored has a very great effect on the course of maturation. In a very damp cellar the spirit will lose alcohol very rapidly and as a resiilt all those changes which are favoured by these conditions will take place with relative rapidity. ”

“ It is usual to give barley intended for patent-still work a rather longer period in the steep and on the floors than in brewery malting, and it is well to treat the steep-water with some antiseptic, preferably lime, as the distiller has not the opportunity of lessening the dangers of bacterial infection at subsequent stages which is afforded to the brewer by the boiling and hopping of the wort. ”

“ Industrial Alcohol.—By industrial alcohol is understood spirit which is employed for other than potable purposes. Alcohol is largely employed in the industries and arts, and for domestic purposes. It is chiefly used for the manufacture of varnish, fine chemicals and dye-stuffs, for pharmaceutical purposes, and in the form of ordinary methylated spirit for lighting and heating. Ordinary methylated spirit for domestic purposes is prepared in the United Kingdom by adding 10 parts of wood naphtha and a small quantity of mineral naphtha to 90 parts of strong spirit. ”

“ The Ilges apparatus yields three continuous streams of fine spirit, fusel oil, and foreshots respectively.
By-products of Fermentation and Distillation. —The main constituent of spirits is, of course, ethyl alcohol â€" spirit of wine—but all spirits contain small but varying quantities of by-products and it is by these that the character of a spirit is determined. The by-products are mainly formed during fermentation, but are also to a certain extent pre-existent in the raw materials, or may be formed during the operations preceding and succeeding fermentation. ”

“ When spirits are made from a purely saccharine material the process of conversion into alcohol is a relatively simple one, but where farinaceous raw products are employed it is primarily necessary to transform the starch contained in them into sugar. ”

“ Patent-still Whisky.—Scotch and Irish patent-still or "grain" whiskies are manufactured usually with a mixed grist of raw and malted grain, and by means of an apparatus usually termed the “patent,” but more properly called Coffey's still. For the manufacture of patent-still whisky a grist containing generally 25% or more of malted barley is employed. The balance consists of maize together with malted and unmalted rye, oats and wheat, and the mixture of grains employed varies at different distilleries. ”

“ The strength of proof spirit at 60° F.—the temperature now generally employed for official calculations—is now officially regarded as being equal to a spirit containing 57.06% by volume, or 49.24% by weight, of absolute alcohol. Spirit which possesses a greater or smaller alcoholic strength than proof is described as being so many degrees over or under proof, as the case may be. The strength is legally estimated by Sykes’s hydrometer, which was legalized in 1816 by 56 Geo. ”

“ The materials most frequently employed are maize, rye, barley malt, raw barley, oats, wheat and potatoes. Comparing the main operations (apart from the actual process of distillation) of the brewer with those of the distiller, it is true that these are identical in the sense that they consist in the conversion of starch into sugar and of the latter into alcohol ”

“ The average yield by the amylo process is from one to one and a half gallons a cwt. of raw material more than is the case with the processes orclinarily employed in the United Kingdom.
Distillation of Industrial Alcohol.—A still intended for the distillation of industrial alcohol should be so devised as to yield a spirit of the greatest strength and purity in the most economical manner. Stills are now constructed which yield in one operation a spirit containing up to 98% of absolute alcohol, and free from all but the merest traces of aldehyde, fusel oil, &c. (foreshots and tailings) . ”

“ It has, however, now been demonstrated that a slightly acid wort is a favourable medium for the free development of the desirable types of distillery yeasts, but that the growth of brewery yeasts, and especially of bacteria, is very much restricted, if not entirely suppressed, in a " soured " liquid. The acid which is the result of a properly conducted souring is lactic acid, formed by the decomposition of the sugar in the wort, by bacterial action, and according to the equation C6H1206 = 2C3H6O3. ”

“ Terpene and terpene hydrate are characteristic constituents of grain fusel. Although the ethereal oils appear to play an important part in determining the character of a spirit, too little is at present known of these substances to warrant any closer description.
Effect of Maturing on the By-products.—That potable spirits (excepting, of course, pure alcohol) and wine are greatly improved by age is an undeniable fact, and one that has been recognized for many hundreds, and even thousands, of years. ”

“ As, however, there is considerable reason for believing that the higher alcohols do influence, at any rate, the flavour of the spirit a brief reference to their physiological action seems to the author not out of place. Broadly speaking, the toxicity of the fatty alcohols increases with their molecular weight. Dujar-din-Beaumetz and Audige found that the lethal dose for dogs was 5–6 grammes per kilo-body-weight for ethyl (ordinary) alcohol; 3·75 grammes for propyl alcohol; 1·8 grammes for butyl; and 1·5 grammes for n-amyl alcohol. ”

“ The advantages accruing from operating, as is the case in the amylo process, with sterile worts are enormous, inasmuch as undesirable bacterial and side fermentations are impossible. The quality and yield of the alcohol is, owing to this fact, considerably improved. The fact that no malt is employed leads to a further very considerable economy. ”

“ Thus one inventor, acting on the alleged fact that spirits are improved by lengthy journeys, suggests that a miniature railway, with numerous obstacles to augment the rolling and shaking action, be laid down in the distiller’s warehouse. ”

“ It is therefore possible, by working on proper lines, to remove the whole of the fusel from the mash by a single operation. By subjecting the vapours so obtained to a carefully regulated dephlegmation, the fusel oil condenses, together with the steam and a certain proportion of alcohol â€" in practice 15%. By further cooling the liquid so obtained the fusel separates out, and, being specifically lighter, rises to the surface of the watery spirit, and is then easily removed. ”

“ The author has, however, shown conclusively that this is not the case, but that on the con- trary the higher alcohols generally increase during maturation. This decrease is not absolute, but only relative, and may be due to the fact that the higher alcohols are less volatile than ethyl alcohol. There is a decided increase during maturation of both the volatile and non-volatile acids. On the whole also the esters and aldehydes generally tend to increase, but not to so great an extent as was formerly believed to be the case. ”

“ Concerning the changes which take place during maturation, it was formerly believed that the higher alcohols decreased with age, and that the main reason of the improvement noticeable in mature spirits was due to this fact. ”

“ With regard to the consumption in gallons per head, Denmark stands first with 2.4, then follows the Austro-Hungarian Empire, with 1-98, Germany with 1.43, Holland with the same figure, France with 1-37, Sweden with 1.36, the United States with 1.26, Belgium with I -10, and last the United Kingdom with 0.91. The consumption in Russia is about equal to that of the United Kingdom. ”