Page:The American Cyclopædia (1879) Volume III.djvu/265

 BKEWING 259 radicles, which have become brittle and have fallen off, are separated by a wire sieve. The preparation of the wort is the next process in the art of brewing. Ordinarily the brewer commences here, because he generally buys his malt of the maltster. The process consists of three different stages: 1, mashing, or the ex- traction of the saccharine material from the malt ; 2, boiling the wort and adding the hops ; 3, cooling. The mashing is performed in a vessel called the mash tan, which is a largo tub from six to eight feet in height and from twelve to fifteen feet in diameter, and capable of containing from 100 to 300 barrels. It is made of wood and bound with iron hoops, like an ordinary tub, which it resembles, except that it is usually larger at the bottom than at the top. It is furnished with machinery for stirring the mash, and has a double bottom, the upper one, which is from five to ten inches above the lower, being perforated with small holes to allow the wort to pass through. Mashing has for its object the conversion of the unchanged starch left in the malt into dextrine and grape sugar, and the extraction of it, to- gether with the dextrine and sugar already form- ed in the malting, and also of the gluten which remains, by means of water at a suitable tem- perature ; thus forming a solution which is called unhopped wort. An important agent in effect- ing this is the diastase which was produced during germination, and which still remains in the malt. To appreciate the nature of the operation, it is necessary to be acquainted with the following facts: The dextrine, or starch gum, which ia the first product of the action of malt upon starch, may be preserved in that state, or still further changed into grape sugar, according to the temperature at which the mixture is digested. If we take eight or ten parts of malt and stir it in about 400 parts of water at 80 F., then raise it to 140 and stir in about 100 parts of starch, and then further increase the temperature to 158, and maintain it between that and 167 for about half an hour, the milky, pasty solution becomes fluid and transparent. The starch is converted into dextrine, and if the solution is now raised to the boiling point and evaporated, the dextrine will be obtained in the form of a viscid gum, which is used in the arts under the names of starch gum and British gum, although it is prepared by another process. The raising the tempera- ture of the solution to the boiling point has deprived the diastase of its peculiar property of transforming dextrine into sugar. If, how- ever, the temperature had been kept between 158 and 167 for two or three hours, the dex- trine would have been converted into sugar by the continuance of the saccharine fermentation, of which tho transformation of starch into dex- trine is a part. This is what takes place during the process of mashing, and explains why it is performed at a certain temperature, and why great care ought to be taken that the water is not too hot when turned upon tlie malt. flashing is usually performed in the following manner: Water, at a temperature of 160 to 165 F., is introduced into the tun beneath the false bottom, while at the same time malt which has been crushed between iron rollers is poured in at the top. The proportion of malt and water used in the preparation of wort for beer of ordinary strength, is about one quarter of malt (352 Ibs.) to 220 gallons of water, or in the proportion of 1 to 5 by weight. This will yield a wort having a specific gravity of about 1 - 06, and containing about 14'66 parts of malt extract in 100 parts of liquid. Strong beers, like Burton and India ales, are made from a heavier wort, while schenkbier, or draught lager, and other light kinds are made from lighter worts. At the commencement of the mash all the malt is run into the tun at once ; if it were not, there would be a difference in time at which different portions would be acted upon, and there would be in other re- spects interferences with the proper conduct of the process. The water is not all let in at one time. At first enough is added to the malt to allow of thorough mixing by the revolving paddles, or agitators, which move around in the tun. After standing fifteen or twenty minutes more water at the same tem- perature, or perhaps two or three degrees higher, according to the judgment of the brewer, is turned in, using altogether for the first setting a little less than one half of the whole quantity to be used in the brewing. The mash is again thoroughly stirred and allowed to stand about two and a half hours. Those brewers who do not care to have the starch mostly converted into dextrine and grape sugar during the first setting do not let the mash stand quite so long; but it is generally con- sidered better to have the transformation well advanced during the first setting. The wort, as the liquid extract is called, is now drawn off into an underback (lower vessel), from which it is afterward pumped into the boiler. The underback is frequently dispensed with in mod- ern breweries, and the wort is drawn imme- diately from the mash tun into the steam boiler which is now preferred to the old copper boiler, with a fire under it. When the wort is run into the boiler it receives its proper allowance of hops. This prevents the occurrence of changes which might interfere with the fer- mentation, and prevent the beer from attaining its finest quality. The wort, when drawn off, should be transparent and about the color of the malt from which it is extracted. Turbid- ness indicates that it contains unaltered starch, which would cause the beer to become sour. This danger furnishes an argument in favor of allowing full time for the first setting. A little more than half of the water which remains to be added is now introduced at a temperature of 167 into the tun, stirred with the remaining malt, and allowed to stand from half an hour to fifty minutes. It is then drawn off into the underback, or directly into the steam boiler as