The liquid which now runs from the mash-tun into the boiling-copper contains all the ingredients which constitute what we may call the body of the beer; it is the extract of a highly nutritious grain, gained in such a way as to justify the designation of liquid bread, which an eminent chemist has assigned to malt liquors. But all the nourishing qualities of the grain have not been extracted; a very large proportion, comparatively speaking, remain in that part of it for which the brewer has no further use. In the brewery under description these grains are conveyed through large pipes from the mash-tuns to the ground floor, or, rather, to an arch-way where wagons may be brought to receive them. They are used as food for cattle and have proved to be the best nutriment for milch-cows. According to the exhaustive analysis made by the Agricultural Experiment Station of this State, and many other investigations, brewers’ grains, even when no longer perfectly fresh, are usually nourishing and, when fed to milch-cows, tend to increase the quantity and enhance the quality of the milk. It is estimated that no less than two-thirds of the bulk of brewers’ grains, as they issue from the mash-tun, consist of water, and this moisture not only militates against the transportation of the grain to rural points, but also accelerates decomposition—two reasons which have prevented a more general utilization of the grains by dairymen. A number of grains-drying machines have been invented, and we learn of others in course of construction, by which the grains may be profitably dried and preserved.
BOILING THE
WORT
The boiling of the wort in these three huge coppers is another one of the essential phases of brewing. The heat required for the boiling is furnished by boilers which send a continuous current of steam through the coils fixed in the copper. These coppers have covers with small sliding doors, which, during the process of boiling, are rarely opened except to enable the brew-master to make his tests. Were it not for these covers, the boiler-room would be enveloped in an impenetrable cloud of steam, which would greatly hamper all manipulations. As it is, the steam finds an outlet through a large pipe or flue fixed on top of the copper. It is at this stage that the hop is added to the wort, but not until after the latter has boiled a sufficient time. Usually, the boiling requires four hours; at the expiration of the third hour, or still later, perhaps, the brewer will empty the contents of several large sacks full of aromatic hops into the copper, thus adding the bitter principle to the saccharine. The proper treatment of the hops at and during this stage always has been a matter concerning which few brewers shared the same opinion; but of late scientific investigations have removed many prejudices which arose from a misconception of the nature, ingredients and functions of the plant. At present, the average brewer fully understands that he can extract the essence of the hops without excessive boiling. The object of the boiling is: 1. To concentrate the wort; 2. To extract the essence of the hop; 3. To coagulate the unchanged albuminous substances and cause them to settle, together with the unconverted starch which, if allowed to remain intact, would materially militate against the preservation of the beer. But this does not do justice to the important function of hops; at least it is to be feared that, to the average reader, it will not convey a clear idea of the action of this tender plant upon the wort. Without it, beer would be nothing more than fermented barley-juice, which, as we have seen, was known to the most ancient nations. Without it, beer could not be preserved for any length of time, and both in appearance and flavor would be greatly inferior to the drink of to-day. Hence, hops not only impart to beers their pleasantly bitter and aromatic flavor, but they also assist in clarification and produce the preservative qualities of the liquid. The two principal substances which the hop-cone yields when boiled, are lupulin and tannin, and it must be the brewer’s aim to extract these in just that proportion which the condition and quality of his wort require. Injudicious handling of the hops may result in an excess of tannin and a deficiency of lupulin, and may otherwise work injury to the finished product. The diminutive sparkling grains of the hop-flower, called lupulin, are closely wrapped up in the center of the hop-cone, and should be laid bare before the plant is placed in the copper. To this end most brewers break up the hops, and the writer was shown a most ingenious and yet exceedingly simple machine which performs this operation in a highly satisfactory manner.
Hops, as delivered at the brewery, are packed in large bales, each weighing 180 pounds; the quantities required for immediate use are taken out of these bales, broken on the machine above referred to, and then placed loosely in large canvass bags, provided with hoop-like handles. As a matter of course, these quantities are all carefully weighed before being dumped into the copper. Scientific observation and practical experience have taught the brewer not to boil the hop too long. Formerly the plant was boiled “all to pieces,” the object being to expedite the precipitation of the albuminous wort by means of the extracted tannin. At present, the boiling time is reduced to a minimum, and yet, by reason of the opening of the hop-cone, the effects and essential functions of the hop are not in any manner impaired.
In the purchase of hops, the brewer must use good judgment and great care so as to secure an article rich in lupulin, fully mature, not too old, cleanly picked and properly dried. If he obtains such hops, he may still have room for complaint on account of the lack of that flavor which is the result of long-continued cultivation and the natural advantages of a favorable soil. The latter causes have made Bohemian hops famous all over the world. Any brewer who strives to produce the very highest grade of beer will always use a certain proportion of these extra-aromatic hops in conjunction with the domestic product. For all practical purposes, however, American hops are as good as, if not better than, the average foreign article, with the exception of a few varieties, the production of which is also confined to a rather narrow territory.
COOLING THE
BREW
When the boiling is completed, the brewer again descends to a still lower floor, where we see, besides many engines, pumps and other gear, a large black rectangular tank which is placed directly under, and connected with the boiling-coppers. This is technically called a hop-retainer or hop-back; the former term undoubtedly more intelligible than the latter, and certainly more appropriate because the function of this tank is to check or retain the hops, while the hopped wort, flowing through open valves in the bottom of the coppers, is being rapidly pumped back to the top floor, where an expansive iron receptacle called the cooling-tank, stands ready to receive it. Poor John Barleycorn! In different conditions he has now made this same trip up and down for the fourth time, and yet the end of his journey is still far off. The contrivance which effects the retention of the hops consists of a perforated false bottom within the hop-back, or, in other words, of a sieve equally as large as the iron tank into which it is fitted, and so fixed as to leave between it and the real bottom of the vessel a sufficient space for the reception of the wort. At this stage, the head-brewer thinks of but two things, namely, to send his wort to the cooling-tank as rapidly as possible and to have it reach its destination clear and brilliant. For the latter purpose he allows the wort to settle in the hop-back for about twenty minutes; this done, he adjusts the pumps, sets them in motion, and then ascends to the top floor to watch the steaming liquid, as it issues from the pipe and, with a sound between a hiss and a roar, rushes into the tank. If we wish to form an idea of the shape and dimensions of this cooling-tank, we must do it now, for in a few moments, as the hot liquid accumulates, a dense cloud of steam, fraught with the enlivening aroma of the hops, begins to fill the immense room, rendering everything indistinct, except when a particularly strong gust of wind rushes through the wide openings in the lattice-work of the windows and for a moment lifts the vaporous veil. The shape of this vessel is that of a gigantic rectangular pan; its depth is three feet; its lateral dimensions are 30 x 42 feet; its capacity equals that of two of the three boiling-coppers, each one of which holds three hundred and seventy-five barrels.
Although he has the most perfect refrigerating apparatus at his command, our brew-master now evinces considerable anxiety; he is pretty sure of the usual result of his operations; but he knows “there’s many a slip between the cup and the lip,” or, rather, between the cooling-tank and the fermenting tun; and right here appears to be the only loophole which human ingenuity left to chance. His object is to reduce the temperature of the liquid and render the wort properly amenable, in the desired measure, to the action of the yeast which he will presently add to it, and thus place it in a fair way for the beginning of fermentation. But unless this is done rapidly, the wort may turn sour, and besides, many believe that other dangers usually accompany a protracted exposure of the liquid to the open air. In many breweries, particularly those situated on depressed ground, or hedged in by other high buildings, artificial means are employed to accelerate this first stage of the cooling process.