William Black

“ Fermentation is undoubtedly as delicate a process, and perhaps as little understood, as any other connected with chemistry; but upon a regular and successful fermentation, or the contrary, must depend the good or bad quality of the beer. Such trifling causes, however, affect this process, that a brewer must not only have a distinct and extensive knowledge of chemistry, but also be what is termed a good manipulator, with great skill in the operative department of the business, before he can reasonably expect to brew uniformly good beer. ”

“ I trust I may be excused in drawing the attention of the meeting of the British Association to a short notice of the injurious influence which electricity exerts on the fermentation of the worts of the brewer and the wash of the distiller. The powerful and injurious effects produced by this agent in the manufacture of beer, I endeavoured to point out, in a little work, lately published, on Brewing; which, although it has excited some notice among a few practical men, yet the subject has not received that attention which its great importance deserves. ”

“ We are now prepared, however, to assert and prove, that when worts are perfectly sound in all the stages of the process, their fermentation will at all times go on regularly and uniformly, if properly managed, and with sound yeast. The only difficulty, therefore, is, to know when any such unsoundness has actually taken place. A slight knowledge of chemistry will then not only materially assist us in tracing the evil to its cause, but also enable us, in after brewings, to prevent its occurrence, should it even proceed from atmospheric influence. ”

“ All brewers who make their own malt, have kilns always at hand; and there can be no doubt that every brewer who can command the means, ought to make his own malt: he can then at all times so modify the colour and flavour, as to produce in his beer those which are most desirable to his customers. When the brewer is necessitated to purchase instead of making his malt, it is in all cases very desirable that he should have a kiln in his premises, for the purpose of re-drying malt which has suffered injury by exposure to the atmosphere, or by imbibing moisture during a sea voyage. ”

“ If we find that in one brewhouse, constructed in a certain way, every thing succeeds, while in others, differently constructed, nothing will succeed, have we not a right to suppose that this must be owing to the different construction of the said brewhouses? and that, therefore, the process of brewing must be pursued with reference to the proper chemical laws, in every respect the same as in producing the nicest chemical compounds. ”

“ Locality, so far as malt is concerned, may no doubt have an influence; some districts produce much finer qualities of barley than others, and of course, much finer and better-flavoured malt. The flavour of beer must of course depend on the quality of the materials which may be used in manufacturing it, and also on the mode of manufacturing it. No further importance, however, can be attached to locality; as we can always in any place find water sufficiently fit for brewing, and by a proper construction of the form our own locality, as often has been and can again at any time be proved. ”

“ We think enough has already been advanced in the chapter on Electricity, to point out the injurious effects of mixtures of metals in the construction of brewing utensils; and we have little doubt that a great proportion of the inferior beer which we now see, is produced by the electro-chemical action, proceeding from the above-mentioned mixture of metals. As brewing, therefore, is a strictly chemical process, the laws of chemistry, by which it can alone be safely directed, should be much better understood than they have hitherto been by all connected with the trade. ”

“ How then can it be fit for brewing?
In some parts of the kingdom, however, no other water can be procured, and we have seen it impart putrescence to the beer, which could be discovered when smelling or tasting it. In all such cases, the water should be boiled, and allowed to cool naturally before mashing; or still better, a quantity of charcoal and lime should be boiled in it, which will, in some measure, correct the putridity. Would the action of chloride of lime be advantageous in such cases? ”

“ Although, generally speaking, we object to all drugs in brewing, it would be folly to suppose that we may not occasionally find the benefit of resorting to such simple chemical remedies as may be found necessary, for properly cleansing the utensils, and removing unsoundness. Some distinct chemical knowledge is therefore necessary, as we might otherwise employ deleterious substances for these purposes. The practice of drugging is now rarely employed; and we know, that in London, no respectable house will, on any account, permit it. ”

“ This sufficiently shows why brewers who go from one brewery to another, cannot arrive at the same successful results with regard to the quality of the beer, although they pursue precisely the same system, and even on some occasions employ the same materials as before. They are thus, from want of chemical knowledge, left completely in the dark, without the possibility of tracing causes and effects. This shows the absolute necessity of applying the discoveries of chemistry, as in other arts, to account for and rectify these anomalies, which without such aid cannot be effected. ”

“ On the injurious influence of Electro-chemical Action in the Process of Brewing.
It is now admitted that electricity is a powerful agent in all processes both natural and artificial. Wherever heat is liberated spontaneously in any process, it must proceed from one or more of the substances employed, acting upon others of a different nature; and when heat is thus produced, it may be supposed to proceed from chemical action, and thus evolving electricity.
Fermentation is a process of this nature, and the production of alcohol may be said to be partly effected by galvanic or electric action. ”

“ That brewed in Bavaria has lately got into great repute, which is chiefly owing to its having been noticed in the writings of Professor Liebig, who there states that its superiority is in consequence of the adoption of, or perhaps the adhering to, a different mode of fermentation to that now practised in this country.
We know, however, that the same mode of culture will not suit every soil, neither will the same process of brewing answer in every climate or even district, nor will the same description of beer please every palate. ”

“ Many variations in chemical actions obviously take place, when no alteration of the temperature or other sensible qualities of the surrounding atmosphere can be observed, by which they might be produced. We are consequently inclined to think, that changes take place in the electrical states of the earth and air, not manifested to us by the phenomena of thunder and lightning, by which variations may be produced in chemical actions, and probably, chemical affinities brought into play, which might remain quiescent without their agency. ”

“ Others, and those very various, are famed for giving the London porter flavour; and the ignorant brewer is induced to use them, from being told by those quacks that the great London houses do the same. We can assure these mistaken persons, however, that no great London house uses, now-a-days, any ingredient disallowed by law; and that no other flavour is given than what is produced by malt and hops.
When harmless ingredients are used for giving flavours, they cannot be particularly condemned: they however subject the brewer, when discovered, to the penalties of the law ”

“ Although fermentation has always been considered a very uncertain operation, and subject to every fluctuation of weather, we entertain some doubts upon that subject, and are also inclined to think that the causes influencing fermentation are not so little under control as may be generally supposed. If alcohol be the production of a regular chemical action during the process of fermentation, by disturbing the progress of that action, we will no doubt materially interfere with the results. ”

“ In brewing ale or any description of beer of very high specific gravity, raw worts cannot well be dispensed with, as we should not get the proper extract from the malt, so as to throw it into the beer, without turning over in the mash-tun a much greater quantity of liquor than is wanted for the production of beers of that gravity; but wherever we have an opportunity of turning over the malt about six barrels per quarter, there can be little doubt but that the whole gravity worth having can be obtained without having recourse to a raw wort in the mash-tun. ”

“ Now as the wine from grapes raised on one soil is inferior to wine from grapes produced on another, so every farmer, from experience, will tell you, that such and such soil is not fit for barley; and there can be no doubt that barley grown on certain soils will make inferior malt. In such cases the water used in brewing is often blamed, while the inferior malt, which is the real cause, is blameless. ”

“ We have always contended that long fermentations are more hazardous than the shorter processes, it being understood that the temperature of the fermenting tuns can be controlled by proper means. It cannot be disputed, that when worts are kept a fortnight, or perhaps more, in the gyle-tun, they are much more liable to be injured by the different atmospheric fluctuations which may take place during that period, both with regard to the influence of electricity and temperature, than they can possibly be in a period of from forty to seventy hours, or sometimes less. ”

“ It is of material consequence to the brewer to have the best malts for the purpose of brewing. Some brewers, when working with inferior malt, think that an additional quantity will compensate for quality. This is, however, an erroneous opinion. Inferior malts can never impart the same mellowness and richness to ale or beer as those of superior quality. From using inferior malt, we also run a risk of having unsound worts. The best, therefore, will be found the cheapest. ”

“ The best and most proper mode of storing and keeping beer is well worthy of the greatest attention. There are, however, many contradictory opinions upon this subject. Some think that all beer, but particularly ale, should be flattened, as it is called, before being stored in vats or casks. For this purpose, where slow fermentation and skimming are practised, large open vessels or tanks are provided, into which the beer is run, after having been a sufficient time, as it is considered, in the gyle or fermenting tun. ”

“ Chemistry has, however, superseded witchcraft, in every process dependent upon its own laws. The process of brewing being strictly chemical from beginning to end, must be subservient to the laws of chemistry, and until these laws are understood and applied, no uniformity can be expected. In some chemical processes, the slightest variation will produce very different results. By using vessels made of certain improper materials in some chemical processes, it is possible to compound deadly poisons, instead of wholesome medicines. ”