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BEER.

gyle-tun, chiefly with the view of observing the progress of the heat, which is low atfirst, but afterwards often increases half a degree per hour, and subsequently decline?, asthe fermentation approaches its conclusion, till at length the heat becomes uniform, orsometimes decreases, before the fermentation is finished, especially where the quantityoperated upon is small.

Some brewers recommend, when the fermentation is carried to its utmost period, to addabout 7 lbs. of wheat or bean flour to a gyle-tun of 25 or 30 barrels, at the lime of clean-sing, so as to quicken the discharge of the yeast, by disengagement of more carbonic acid.The flour should be whisked up in a pail, with some of the beer, till the lumps are bro-ken, and then poured in. By early cleansing, the yeast is preserved longer in a stateproper for a perfect fermentation than by a contrary practice.

For old ale, which is to be long kept, the heat of the fermentation should not exceed75°, but a longer time is required to complete the fermentation and ensure the futuregood flavor of the ale.

For porter, the general practice is, to use from 4 to 4J lbs. of hops per barrel for keep-ing ; though what is termed mild or mixing porter, has not more than 3 or 3 J lbs. Theheat of fermentation must not exceed 70°, and begin about 60°. If the heat tend ’to in-crease much above that pitch in the gyle-tun, the porter should be cleansed, by means ofthe stillions. At this period of the fermentation, care should be taken that the sweetnessof the malt be removed, for which purpose more yeast may be used than with any otherbeer of the same strength. The quantity is from 3 to 4 lbs. per barrel, rousing the wortin the gyle-tun every 2 hours in the day-time.

When the plan of cleansing casks is not employed, the yeast is removed from thesurface of the fermenting tun by a skimmer, and the clear beer beneath is then drawnoff into the ripening tuns, called siore-vats, in whiSh it is mixed up with different brew-ings, to suit the taste of the customers. This transfer must take place whenever the.extrication of carbonic acid has nearly ceased; lest the alcohol formed should dissolvesome of the floating yeast, acquire thereby a disagreeable taste, and pass partially into.the acetous state.

In this process, during the formation of vinous spirit at the expense of the sugar, thealbumen and gluten diffused through the beer, being acted upon by the alcohol, becomeinsoluble ; one portion of them is buoyed to the top with the carbonic aqid gas, to formthe frothy yeast; and'another portion falls to form the bottom barm. The former con-sists of the same materials as the wort, with a large proportion of gluten, which formsits active constituqpt; the latter is a peculiar deposite, consisting of the same gluten mixedwith the various dense impurities of the wort, and may be also used as a ferment, but iscruder than the floating yeast. The amount of yeast is proportional to the activity of thefermentation, or extrication of carbonic acid gas, as also to the heat of the mashing pro-cess, and the quantity of starch or flour unaltered by germination. Pale malt affords,usually, more yeast than malt highly kilned. When the yeast becomes excessive, fromtoo violent fermentation, it should be skimmed off from time to time, which will tend tocool the liquor and moderate the intestine changes.

After the beer is let down into the close store-tuns in the cellar, an obscure fermenta-tion goes on, for a considerable period, in its body, which increases its spirituous strength,and keeps up in it a constant impregnation of carbonic acid gas, so as to render it livelyand agreeable to the taste, when it is casked off for sale. It would appear that beer isnever stationary in quality, while it is contained in the tuns; for the moment when itceases to improve by the decomposition of its residuary sugar, it begins to degenerateinto vinegar. This result may be produced either by the exhaustion of the saccharine,or by the fermentative matter. The store cellar should therefore be under ground, freefrom alternations of temperature, vibrations of carriages, and as cool as possible. In thegreat London breweries the fermentation is rendered very complete in the cleansingbutts; so that a slow and steady ripening is ensured in the great store-tuns. The gyle-tuns are too capacious to permit the fermentation to be finished, with either safety orsufficient despatch in them.

V. Of ripening different kinds of Beer. —The varieties of beer depend either uponthe difference of their materials, or from a different management of the brewing processes.

With regard to the materials, beers differ in the proportion of their malt, hops, andwater; and ih the different kinds of malt or other grain. To the class of table orsmall beers, all those sorts may be referred whose specific gravity does not exceed 1-025,which contain about 5 per cent, of malt extract, or nearly 18 pounds per barrel. Beersof middling strength maybe reckoned those between the density of 1-025 and 1-C40;which contain at the average 7 per cent, or 25 pounds per barrel. The latter maybe made with 400 quarters of malt to 1500 barrels of beer. Stronger beers have aspecific gravity of from 1-050 to 1-080, and take from 45 to 75 quarters of malt tothe same quantity of beer. The strongest beer found in the market is some of theEnglish and Scotch ales, for which trom 18 to 27 quarters of malt- are taken for 1500