A variety of plane may be employed for increasing the quantity of dextrine. Dextrine when in large quantities, after the worts are fermented, gives what ie termed roundnesa of flavour to the beer, and ia therefore preferable for porter, atout, and the heavier class of alea. The dextrine of the wort may be increased hy modifying the Bavarian method. Or the diaataae may be rendered inert by infusing at 38° to 49° (100° to 120° F.), raising the temperature to 60° (140° F.), with tolerable rapidity, and when the infuaion is complete at that temperature, again increaaing to 79° (175° F.), allowing digestion to go on at that temperature. Another plan ie to add unmalted grain, barley, or maize, but in this case the unmalted grain should be kiln-dried at a temperature of 100° to 110° (212° to 230° F.), in order to render the albuminous matters leas aoluble, to decom pose them in the presence of the moisture of the grain, to produce empyreumatic matters, and to obtain colouring products. Practically this treatment yields a malt not containing diastase.
Having conaidered the theoretical principles of mashing, aa well aa having deecribed the most approved processea, it may he advantageous to deal shortly with the latter, from a more practical point of view. The practical brewer should regard mashing as a triple, rather than a single procese ; and should feel assured there is nothing to prevent the obtaining of good beer, when proper heath are taken. Like the extraction of the juices of meat in the making of aoupa, the extraction of the albumen from t,he malt depends upon the non-coagulation of the albumen at the commencement of the mashing. In the most approved practice, it is generally agreed that the heat of a pale beer maah, when all the malt and water are put in and finally mixed, ought to be 71° (160° F.). It is at thia heat of the first mash that the best flavoured extract is produced, and the entirely chemical action of saccharification occurs. But this temperature must be gradually approached, because its sudden application would coagulate the albumen of the malt. The triple nature of the mashing process may be practically regarded as consisting in saturating, sacchari fying, and extracting, to prevent Betting or coagulation.
The malt ahould be wetted at a heat that would give in the mash tun 64° to 66° (148° to 152° F.), or several degrees below the best saceharifying point. When goods are thoroughly wet, water is applied at a higher suitable heat, with the internal rakes of the mash tun revolving, until the gooda are at the temperature of aactharification ; after four or five hours' continuance of the saccharifying heat, the temperature ahoulcl be reduced to that at which the brew began. Maahing, as performed in Steel'a or other saturator, may commence at 64° for light, and 66° for heavy beers ; this means mixing about barrel of water to the quarter of malt, and finishing with a firkin to kilderkin, to a quarter, more of water at 87° to 90° (190° to 195° F.). The copper heats for the
water employed will average about 77° (170° F.).
A plentiful supply of cold water should adjoin the hot-water pipe, to secure regulating power.
When the mixture is in the mash tun in a saturated condition, the copper water, at 87° to 90° (190° to 195° F.), should bo let in without delay, and the rakes kept going, until the goods are uniformly heated to 68° (156° F.). These heats are for perfect malt. For imperfect malt, or half barley, lower saturating heats may be nsed advantageously, but imperfect malts should never be used for fine beers, as neither a sufficient nor economical extract, nor good flavour can be obtained in the mash tun. The preceding observations refer to the first mash.
The draining and extracting of the goods ought to proceed within two hours from the completion of the mashing operation. The mash should not be tapped through oue cock, but should be drained through three or more, placed in the bottom of the mash tun. Draining should at first proceed slowly, until sufficient grains have settled around the cocks to act as a filter, which occurs in about twenty minutes. If the extract is to be completed by repeated mashings, the cocks, after the first mash is run off, should be closed, and the mash tun recharged with hot water, in such quantity as to make up the second mash of the brew, at a goods' heat of about the same as the first mash. The flxst mash ought to lie about an hour, and when run off, the third mash, if required, should be made up for a temperature with the goods of 66° (150° F.), and this mash should lie for half or three. quarters of an hour only. The copper-water heats, and quantities of water required for these two after mashes are only to be obtained from actual experienoe with the particular plant The second mash water will require to he about 79° (175° F.), and the third about 74° (165° F.), for mashes of ordinary quantities. This process gives roughly a three-maah brew. As it is difficult for the brewer to calculate these quantities accurately, it is preferable to keep the mash waters short of the quantities required, and to sparge at the end, with tepid water, to make up the copper charge. Another plan approved of by many brewers, is to make two mashes of reasonable thickness, and sparge up the remainder of the charge. In this case the sparge water ought to be of such a temperature as would allow the heat of the goods to fall to 66° (150° F.).