Page:Encyclopædia Britannica, Ninth Edition, v. 4.djvu/318

274 art of making the materials we have described into beer. While brewing cannot bo considered a difficult or a mys terious art, good materials, a good method, and strict attention being the secrets of success there is no process in which rules are of less avail. To obtain complete success, it is necessary that the brewer shall have formed an opinion of his materials from personal observation, and that he should be thoroughly acquainted with the brewery in which they are to be used. It is not too much to say, that the same heats and quantities cannot properly be used in any two breweries. Bearing this difficulty in mind, we shall endeavour to point out where instructions may be safely followed, and where the circumstances of locality, &c., will subject them to certain modifications which cannot be strictly defined in an article like the present. Brewing consists of eight distinct processes, which may be classed as follows:—

1. Grinding. 2. Mashing. 3. Sparging. 4. Boiling. 5. Cooling. 6. Fermenting. 7. Cleansing. 8. Racking and storing.

Grinding.—This is a very important operation; for, if im perfectly performed, some of the &quot; goodness,&quot; or &quot; extract &quot; as it is called, will be left in the grains after mashing, thus entailing a heavy pecuniary loss on the brewer. The malt is crushed rather than ground between plain metal rollers ; this is enforced by law, for the purpose of facilitat ing the examination of the grain as to whether it has been malted or not. Previous to the passing of the Act fraudulent brewers mixed raw grain with their malt, grinding it all up fine, to prevent identification. Each corn should be well broken, that the mashing water may have free access to every particle ; on the other hand, if the malt be ground too fine, it is liable to &quot; set,&quot; that is, form a paste in the mash tun. When this happens it will be difficult to draw the wort off, and when off it will con tain so much of the coarser portion of the grain that the flavour and keeping qualities of the beer will be impaired. If possible the crushed malt should stand about twenty- four hours before being mashed, care being taken to protect it from air or damp, the object being to allow the heat generated by passing through the rollers to escape.

Mashing is the process of infusion, or mixing the malt with water at such a temperature as shall not only extract the saccharine matter existing in the malt, but shall also change the still unconverted starch into grape-sugar. This is accomplished by the principle called diastase, the power of which we have shown under the head of malting. Many mashing-machines have been invented, and many are in use. In some the malt and the water are simply brought into conjunction, and then mix them selves as they fall into the mash-tun others, driven by steam, perform the operation of mixing more leisurely, and, in some cases, more effectually. The old-fashioned method of mashing is by means of iron rakes. These rakes are fixed on arms extending from the centre of the tun, and are so constructed that when set in motion, no portion of the mash escapes them. When rakes are used a portion of the mashing water is first run into the tun, and part of the malt ; the machinery is then started, and, whilst the rakes revolve round the tun, the remainder of the malt and water are added. The heat of the mashing water is a very important point ; the particular temperature must depend upon the quantity and quality of the malt, and the situation of and amount of radiation from the mash-tun. Not less than two or more than three barrels of water should be run on to every quarter of malt, and the heat of the water should be such, that, when all has run on, that is, when the malt has combined with the water, the temperature of the mash shall not be lower than 148 or higher than 152. In some breweries this result will be obtained by mashing at 168; in others it will be necessary to go as high as 180. Neither of these heats will do any harm so long as the heat of the mash does not exceed 152. Most brewers and chemists think that, to ensure the best results, it is necessary for the mash to stand at least two hours. It would appear, however, that this belief has no solid foundation. Recent observations have convinced the pre sent writer that an extract as good, and perhaps sounder, is drawn from a five minutes mash as from one that has stood two hours, a fact which any brewer can test for himself. The wort should be drawn off by means of several pipes running from different parts of the mash-tun. It must be run off slowly at first, or the malt in the tun (&quot; goods,&quot; as it is now called) will be drawn down so tightly that it will be difficult for the sparging water to run through it. It is a good plan to probe the mash now and then with a thin stick ; if the &quot; goods &quot; feel tight, and difficult to pene trate, the wort is being run off too quickly.

Sparging.—When about half the wort has run off the mash, the operation of sparging should be commenced, the object of that process being to wash out the goodness left in the malt after mashing. The sparging-machine is made and fixed as follows : A bar of iron having an upright pin in the centre is fixed across the mash-tun ; on this pin is placed a copper bowl or pan ; into this pan are screwed two or three arms, extending to the sides of the tun. These arms are about an inch and a half in diameter, and are perforated their whole length with small holes on their reverse side. The hot water being conveyed into the pan fills the arms, and, running out through the perforated holes, causes the arms to revolve round the tun. By this means an equal and continuous shower of hot water is rained upon every portion of the goods. The heat of the sparging water, like that of the mashing liquor, must be modified by circumstances. In brews of less than 10 quarters, 200 will be found to be a good heat ; where larger quantities are mashed 185 may be recommended as a safe temperature.

Boiling.—When the wort runs off the mash no time should be lost in getting it into the copper or boiling back. In many modern breweries the mash-tun is placed immediately over the copper, so that the wort runs direct from the former utensil into the latter. Some coppers are built with an ordinary furnace, others are furnished with a coil ; in the latter case the worts are boiled by steam passing through the coil from the boiler. Many brewers prefer to boil by steam, as it is a cleaner method, and they are able to regulate the operation to a nicety. Where the steam coil is used the boiling back is generally made of wood. While the wort is running or being pumped into the copper, the hops must be added. Here, again, no positive instructions as to quantity can be given. On this point the brewer must be guided by his customers tastes, the season of the year, the length of time the beer has to be kept, and the quality of the hop used. For strong store ales, from 10 ft to 13 Bb of good hops to every quarter of malt is not too much ; whilst for ordinary beers, to be drunk within two months, from G 5) to 9 K) per quarter should suffice. India pale ale and bitter beer require from 18 ft&amp;gt; to 25 ft&amp;gt; per quarter. Various kinds of English and foreign hops can be used in the same brewing with advantage ; the proportions of each kind must be left to the judgment of the operator. Of course, the ranker Bavarian and American hops must not be so freely used as the more delicate English growths. There is a wide differ ence of opinion as to the length of time beer should be boiled. For beers of quick draught, an hour and a half 