406
and carefully incorporated by much manual labor with wooden oars, or in great concernsby the mechanical apparatus used in the breweries. This agitation must be continuedfor 2 or 3 hours, with the admission from time to lime of about 400 additional gallons ofwater, at a temperature of ^190°, to counteract the cooling of the materials. But sincethe discovery of diastase, as the best heat for saccharifying starch is shown to be nothigher than 160° F., it would be far better to mash in a tun, partially, at least, steamincased, whereby we could preserve the temperature at the appropriate degree for gene-rating the greatest quantity of sugar.
If the wort be examined every half-hour of the mashing period, it will be foundto become progressively sweeter to the taste, thinner in appearance, but denser inreality.
The wort must be drawn off from the grains whenever it has attained its maximum.
density, which seldom exceeds 150 lbs. per barrel; that is, ^60 -f- 150 _ or 42
’360
per cent. As the corn of the distiller of raw grain has not the same porosity as thebrewer’s, the wort cannot be drawn off from the bottom of the tun, but through a seriesof holes at the level of the liquor, bored in a pipe stuck in at the corner of the vessel.About one third only of the water of infusion can thus be drawn off from the pastymass. More water is therefore poured on at the temperature of 190°, well mixed byagitation for half an hour, then quietly infused for an hour and a half, and finally drawnoff as before. Fully 400 gallons of water are used upon this occasion, and nearly asmuch liquor may be drawn off. Lastly, to extract from the grains everything soluble,about 700 gallons of boiling hot water are turned in upon them, thoroughly incorpo-rated, then left quietly to infuse, and drawn off as above. This weak wort is commonlyreserved for the first liquor of the next mashing operation upon a fresh quantity of men*and malt.
The English distiller is bound by law to make his mixed worts to be let down into thefermenting tun of a specific gravity not less than 1 '050, nor more than 1 090 ; the Scotchand Irish distillers not less than 1-030, nor more than 1-080; which numbers are called,gravity 50, 90, 30, and 80, respectively.
With the proportion of malt, raw grain, and water, above prescribed, the infusion fi rs |drawn off may have a strength = 20 per cent. = spec. grav. 1-082, or 73 lbs. per barrel,the second of 50 lbs. per barrel, or 14 per cent.; and the two together would have 8strength of 61-2 lbs. per barrel = 17 per cent., or spec. grav. 1 070. From experimentscarefully made upon a considerable scale, it appears that no more than four fifths of t'soluble saccharo-starchy matter of the worts is decomposed in the best regulated fermeh'tations of the distiller from raw grain. For every 2 lbs. so decomposed, I lb. of al»J">spec. grav. 0-825,.is generated; and as every gallon of spirits of the spec. grav. 0-9contains 4-6 lbs. of such alcohol, it will lake twice 4 6 or 9-2 lbs. of saccharine matter 44produce the said gallon. To these 9-2 lbs., truly transmuted in the process, we must a ,^one fifth, or 1-84 lbs., which will raise to 1104 the amount of solid matter employed 1producing a gallon of the above spirits. . , j n
Some distillers mash a fourth time; and always use the feeble wort so obtainedmashing fresh grain. aces-
2. As the imperfect saccharine infusion obtained from raw grain is much morecent than the rich sugary solution got from malt in-the breweries, the distiller oD1use every precaution to cool his worts as quickly as possible, and to keep them clea
any acetous taint. The different schemes of cooling worts are considered undeand Refrigeration. As the worts cool, a quantity of starchy matter is precipit® e^ _ n _it is all carefully swept along into the fermenting tun, and undoubtedly contribu es ^crease the production of alcohol. During the winter and temperate months, v ^ - gdistilleries are most actively at work, the temperature at which the worts are “ on |yusually about 70° F. When much farinaceous deposite is present, the heat may ^ t | ia t65°, because, in this case, a slow fermentation seems to favor the conversion^ ^ ^starch into sugar. In some German distilleries a little chalk is mixed with thecheck acidity.
3. The fermentation. . wm of th«
The yeast added to the worts as a ferment, ought to be the best top 0 j- Iticai
London porter breweries. About 1 gallon of it is requisite for every 2 bushel por .and malt worked up in the mashing process; and of this quantity only a cer secondtion is introduced at the beginning; the remainder being added by degrees, onand third days. r } f t h day>
Should the fermentation flag, a little more may be added on the fourth or b e
and the contents of the tun may be roused by an agitator. About 8 or 9 gat bushe ] s ofintroduced four days in succession to the quantity of worts extracted from t0 the
the farinaceous materials ; or the third day’s dose may be intermitted, ana Jfourth on the subsequent day.