Page:The New International Encyclopædia 1st ed. v. 06.djvu/356

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DISTILLED LIQUORS. 306 DISTILLED LIQUORS. erally used in llie leniioutatioii process. Sadtler stales, in liis Jnduslriul Oryunic (.'luinislry (New York, IStlti), llmt the following advantages are claimed for its use: "(1) by preventing the losses due to secondary fermentation the alco- holic yield is increased; (2) this yield is especially maintained when raw materials of somewhat inferior quality are used. when, with- out the hydrolluoric acid, the yield would he diminished; (3) the development of foaming in the fermentation is largely prevented." In making spirit from beets, sulphuric acid is used during the fermentative process. Much of the beet-spirit is made from molasses derived as a by-product from the manufacture of beet- sugar. J5ut in Trance it is customary to make inferior beets directly into spirit. t)nly a small quantity of yeast is required, and fermentation IS com|)lcted in about twenty-four hours. In the West Indies, the molasses produced in making cane-sugar is utilized in the manufacture of whisky. (iSee Whisky.) The a<ldilion of jeast to the saccharine liquid is unnecessary, be- cause enough nitrogenous matter is j)resent in the molasses to produce spontaneous fermenta- tion. Distillation. The operations thus far de- scribed arc merely preliiiiinarv. They dillVr from those employed in the two fermentation industries, wine and beer making, in that in preparing the liquor for distillation the fermenta- tion process is carried to its furthest limit in order to produce the greatest possible amount of alcohol. The liquid thus prejjared for dis- tillation is technically known as the ira.ih. The still is the apparatus in which the wash is re- duced to vajior and then condensed. In its oldest and simplest form the still consists of a copper vessel, provided with a closed head, connected with a spiral tube, called the irorm. The latter is ]>Iaced in a refrigeratory, or closed, chamber, through which cold water is constantly passing. When heat is applied at the still the spirit begins to rise in vapor, along with more or less steam: these vapors pass through the worm, become condensed by the cold, and dro]) or trickle down into the receiver. The product of the first distillation in a simple still is a weak and impure liquid technically known as low icines. This is then redistilled at a lower tem- perature to deprive it of the water and of the fetid oils which have passed with the alcohol. In 1801 the first groat imi)rovenient in dis- tilling was invented by a workman of ^lontpellier named .dam. I?y making the vapors ris*' from the still through a series of winding passages, maintained at a determinate degree of heat, and deposit part of the water and other impurities, he was able to obtain from wine a spirit of any required degree of purity at one operation. Tliis device was applied by Pistorius to the distilla- tion of washes made from grains. 'ithin recent years many inventions have been made to pro- duce the pire-it and strongest alcohol at the lowest possihle cost. Sadtler divides the differ- ent forms of distilling apparatus into five gen- eral classes: (1) The simple stills alreadv de- scribed, with worm-condcn-^er heated by direct flrinc 12) The simple stills with closed 'wash- warmer.' This is a device for saving fuel by causing the pipe containing the hot vapors on their way to the rcfri<.'erator coil to pass through a vessel containing the wash. Thus the wash is heated to a considerable degree before it enters the still at all. (3) Stills with rectifying 'wash-warmer.' This is a device invented by Dorn, in which the vessel through which the vapor pi|)e passes is divided into two comparl- iiu-nls liy a sheet of cop])cr. The upper and larger compartment .serves as a wash-warmer. Through it the tube conveying the vapors from the still passes into the lower conq)artment, where at first the distillate is condensed. But as the wash is warmed bv the vapors from the still, the distillate in this compartment gives olf alcoholic vapors which pass on and are ci>ndensed in the worm, while the watery portion is allowed to run back into the .still. This rectifying action can Vie increased by intro- ducing two or more chambers between the still and the final condenser. (-11 .Stills with wash- warmer, rectifying, and dephlegmator apparatus for intermittent working. (o) Stills with similar apparatus for continuous working. A dephlegmator is an apparatus for partially con- densing the vapor, by means of metallic dia- phragms. The vapor, coming in contact with these metallic sheets, is chilled, and the watery portion, which condenses most readily, separates and Hows back, while the alcoholic vapors pass on through the pipes to the condenser. The Pistorius apparatus, already referred to, is an iiitermittent dephlegmator. The original inven- tion has been improved successively by (iall, Schwartz, and Siemens, and is much used in Ger- many in making potato spirit. E.Kamples of the fifth class of stills, those with a continuous de])hlegmator apparatus, are the Colfey still, used in Kngland for making grain spirit, and the Savalle still, ised in l"rance in distilling brandy. The Colfey still is particularly well adapted to the manufacture of what is known as 'silent spirit,' that is a spirit which is very strong and pure, but nearly destitute of llavor. For the manufacture of beverages it is not so well fitted because it removes, along with other impurities, a large proportion of the volatile oils which give them their peculiar flavor. For the principles involved in the process sec DlSTlL- I.ATIO.N : KVAI'OBATIO.N ; I'.OlLIMi-PoiXT. Pl-KIFYIXG THE DlSTII.l.KD SpiItlT. If alcohol and water were the only substances that pass over in distillation, all spirits, from whatever source, would be the same. Hut. except to a partial extent in the Cofl'ev still, this is not the c:ise. Brandy, nmi, and whisky owe their dis- tinctive flavors to essential oils derived from the grape, from sugar, or from grain. Other impuri- ties also |)ass over which are unpleasant and unwholesome. The mellowing cITecl of age upon spirits is said to be due to the evaporation or spontaneous combustion of these oils. N'ewly distilled spirits are in general fiery and unwhole- some. The process of removing the impurities from the spirit, by fractional or repeateil dis- tillation, is known as rrrlifinng the spirit. The spirit that is first condensed, in rectifying, is crude and milky. Next comes the clear alcohol, whii'h is cau'.'ht «e[iarately. Last of all comes a weak spirit called fainlx. which is returned to the still. There are certain impurities which cannot be removed l>v distillation. Fusel oil is one of these persistent impurities. Several chemical methods have been proposed for its removal, but the method usually employed is to filter the alcohol, diluted with equal parts of