Cooley's Cyclopaedia of Practical Receipts Volume I Part 110

Hard water is also much to be preferred to soft in brewing stock beers; since by its rendering the alb.u.minous matters contained in the mash insoluble, it prevents the fermentation to which these would otherwise give rise, and so a.s.sists in the preservation of the beer, and in keeping it free from acidity.

The German brewers, however, who do not brew beverages intended to be kept for any time, on the contrary, employ a soft water, by which means the alb.u.minous substances contained in the malt are rendered soluble, and become diffused throughout the beer, and possibly add in some measure to its nutritive qualities. Hard waters are said to have the property, over soft ones, of enabling the beer to retain more saccharine matter, and hence to improve its flavour and to give it more body. The ales of Burton are pre-eminent for their excellent quality and keeping properties. In the neighbourhood of Burton there are extensive beds of new red sandstone and gypsum, by sinking wells into which the Burton brewers obtain the water from which they make their beers. From the subjoined a.n.a.lyses of Burton well waters it will be seen that this water is a very hard one, and contains, besides other salts, a very large quant.i.ty of sulphate of lime.

a.n.a.lysis of the water used in Messrs ALLSOPP'S brewery (Dr Bottinger):--

Amount of ingredients in the imperial gallon, represented in grains.

Chloride of sodium 1012 Sulphate of potash 765 Sulphate of lime 1896 Sulphate of magnesia 995 Carbonate of lime 1551 Carbonate of magnesia 170 Carbonate of iron 060 Silica 079 ------ 6528

a.n.a.lysis of water from a well at the brewery of Messrs Ba.s.s (Cooper):--

Carbonate of lime 993 Sulphate of lime 5440 Chloride of calcium 1338 Sulphate of magnesia 083 ------ 7854

The whole of the water used in the Burton breweries is obtained from wells, and not from the river Trent, as was at one time erroneously supposed. A fact.i.tious Burton water may, it is said, be obtained by adding sulphate of lime and salt to any soft water, in the proportions stated in the above a.n.a.lyses.

Dr C. Graham is of opinion that, although the properties of the Burton well waters are very greatly due to the large quant.i.ty of sulphate of lime contained in them, the chlorides of sodium and calcium are also important const.i.tuents.

The yeast must be fresh and good; and all the vessels and utensils perfectly sweet and clean. If the latter be neglected, even the most skilful brewing will prove a failure.

Process of brewing:--

1. MASHING:--The ground or bruised malt placed in the mash-tun is macerated for some time in hot water, and the infusion (_wort_) drawn off from a hole in the bottom, over which a strainer or false bottom is placed, to prevent the malt pa.s.sing out along with the liquor. During the process of mashing a peculiar principle contained in the malt, called diastase, reacts upon the starch with which it is a.s.sociated, and converts it into grape-sugar. The more completely this conversion is effected the richer will be the resulting wort in sugar or "_saccharine_," and the stronger and more alcoholic the beer produced by its fermentation. It is, therefore, a desideratum with the brewer to mash at the temperature which most fully promotes this important object. The best temperature for this purpose ranges between 150 and 170 Fahr. When more than one mash is made, the first should be something lower than the first-named temperature; the second may be from 175 to 185; and the third as high as 200 Fahr.

If the first mashing has been rightly conducted, the whole of the starch will be converted into sugar, and the action of the second and third mashings is merely to wash out any of the remaining saccharine matter still existing in the crushed grain.

In practice, as soon as the water in the copper acquires the temperature of 170, 45 galls. are run into the mash-tun, and 1 quarter of crushed malt gradually added to it. The whole is now thoroughly mixed with the mash liquor, by means of oars, or machinery, the agitation (_mashing_) being continued for 30 or 40 minutes, when 36 galls. more water from the copper are added, and the whole again well agitated, as before. The mash-tun is now closely covered up, and the mash allowed to repose for about two hours, in order that the diastase may exert its saccharifying power upon the unconverted starch of the malt. At the end of this time the tap is set, and the wort run into the 'underback.' It generally amounts to about 50 galls. The second mash is then made with about 60 galls. of water, at 185 F., and the whole process repeated as before. After an hour the liquor is drawn off, and the malt drained ready for the third mash.

This time only 35 galls. of water are added at 200 F., and the whole is seldom allowed to stand longer than half an hour. It is then run off, and the malt allowed to drain as dry as possible.

In some cases the worts of the first and second mashes only are used for strong beer; that of the third mashing being kept for table beer, or as liquor to mash a fresh quant.i.ty of malt.

Pale malt and mixtures of malt and raw grain should be mashed for a longer time, and at a somewhat lower temperature than brown or high-dried malt.

Instead of making second and third mashes as above described, it has long been the practice in Scotland, and is now becoming common in England, to sprinkle the surface of the grains in the mash-tun with water, at or about the temperature of 180 Fahr., by means of a simple revolving instrument termed a 'sparger,' and to let the liquor drain through the goods and run off by the tap with the last portions of the first wort. By this means the whole surface of the grain is continuously and regularly sprinkled with hot water.

When sugar is used it may be either mixed with the malt in the mash-tun, at the time of mashing, or put into the underback, just before setting the taps, and the hot wort run upon it. The proportions of malt and sugar vary according to the quality of the latter, but, on an average, from 170 lbs.

to 200 lbs. of good raw sugar may be taken as the equivalent of a quarter of malt.

2. BOILING:--The wort is next transferred from the underback to the copper, and heated to the boiling-point as soon as possible, the object of this expedition being to prevent the formation of acid in the wort, by exposure to the air, before undergoing the changes which take place in the copper. As soon as the boiling of the wort commences the hops are added, and the boiling is continued for about 2 or 2-1/2 hours. A longer boiling is highly objectionable, owing to the extraction of a heavy, resinous bitter from the hop, and the danger of losing the volatile oil upon which the aroma depends. For mild beers the worts are seldom boiled so long; for strong keeping ales, sometimes a little longer. The boiling is known to be completed when the liquor 'clears,' as it is called, and alb.u.minous flocks sink to the bottom of the copper.

The hops, strained from each wort, are returned into the copper with the following one.

The average loss by evaporation in the process of boiling varies from 1/6th to 1/7th of the original bulk of the wort. The gravity increases at the same time in about the ratio of 5 to 4; so that if the gravity be, at first, say 32 lbs. per barrel, it will at the end of the operation have risen to about 40 lbs.

3. COOLING:--The wort, under the common system, is 'run off' from the copper into the 'hop-back,' through a strainer which keeps back the hops.

It is then pumped into large square shallow vessels called 'coolers,'

where it is freely exposed to a current of air to reduce its temperature as quickly as possible, in order to avoid acidity or 'souring.' In 6 or 7 hours, or sooner, the temperature should fall to about 60 Fahr. In warm weather the depth of the liquor in the coolers should not exceed 3 or 4 inches; and in cold weather not more than 5 or 6 inches. As soon as the temperature has fallen to about 60 the liquor is 'tunned' and 'yeasted.'

The loss by evaporation and condensation in the coolers varies from 13 to 18 galls. per quarter.

4. FERMENTATION:--The cooled wort is next run into the fermenting tuns or vessels (gyle-tuns). In small brewings these may be casks with one of their heads removed; but under any form they must not be more than 2/3rds filled. The yeast, previously mixed with a little wort, and kept until the whole has begun to ferment (technically termed '_lobb_'), is now added, and after agitation the vessel is covered up, and kept so, until the fermentation is well established. By this time the temperature has risen from 9 to 15.

The quant.i.ty of yeast employed, and the temperature of the wort when it is added, differ in different breweries and for different kinds of beer. It seldom exceeds 2 lbs. per barrel unless the weather is unusually cold, or the yeast old or stale, when a larger proportion is required. The Scotch brewers generally take only 1 gall. of yeast to fully 4 hhds. of wort.

In England, the temperature at which the yeast is added varies from 55 to 65 Fahr. In Scotland, the common temperature is 51 to 52. In cold weather the heat may be 5 or 6 higher than in mild and warm weather, and a little more yeast may also be advantageously employed. In cold weather ale is commonly tunned at 60, porter at 64, and weaker beers at 65 or 70 Fahr. In 'warm weather' strong beer should be 4 or 5, and other beers 7 or 8 cooler than the 'heats' just mentioned. On the small scale, 1 to 1-1/4 pint of yeast may be used to every barrel of strong-beer wort, and 3/4 pint to every barrel of mild-beer wort.

The commencement of the fermentation is indicated by a line of small bubbles forming round the sides of the tun, and in a short time extending over the whole surface. A 'crusty head' soon forms, and then a 'fine rocky head,' followed by a 'light frothy' one. At length the head a.s.sumes a yeasty appearance, the colour becomes yellowish brown, and a vinous odour is developed. As soon as this last head begins to fall, the tun is skimmed every 2 or 3 hours, until no more yeast is formed. The object of this is, not only to check the violence of the fermentation, but also to remove a peculiar bitterness, with which the first portion of the yeast is impregnated. The beer is then put into casks, or 'cleansed,' as it is called. A minute attention to every stage of this process is necessary to secure a fine flavour and a brilliant beverage.

It may be regarded, as a rule, that the lower the temperature, and the slower, more regular, and less interrupted the process of fermentation, the better will be the quality of the brewing, and the less likely to change by age. A little more yeast is required in winter than in summer.

When the fermentation becomes slack in the 'gyle-tun,' a little more 'lobb' is generally added, and the whole is well 'roused up,' On the contrary, if the temperature rises considerably, or the fermentation becomes too brisk, the wort is cooled a little and skimmed, or at once cleansed.

5. CLEANSING:--This consists in running the beer from the gyle-tun into casks, or other vessels, set sloping, so that the yeast as it forms way work off the one side of the top, and fall into a vessel placed below to receive it. In small brewings the beer is often at once transferred from the gyle-tun to the 'store-casks,' which are sloped a little until the fermentation is over, when they are skimmed, filled, and bunged.

The process of cleansing is generally commenced as soon as the 'saccharine' in the fermenting wort falls to about 10 lbs. per barrel, a degree of attenuation which it usually reaches in about 48 hours. Some brewers add a little wheat-flour or bean-flour (about 1/4 lb. per barrel) to the beer in the gyle-tun, shortly before cleansing, to quicken the discharge of yeast; but it is not clearly ascertained whether such a plan is advantageous, or the contrary.

6. STORING:--As soon as the fermentation is concluded, which generally takes from 6 to 8 days, or longer, the clear liquor is pumped into the store-casks or vats, which are then closely bunged, and deposited in a cool cellar, if not already there, to mature. The preference, which at present exists in most parts of the United Kingdom, is for mild, freshly-brewed malt liquors; the good old or mature-vatted beer being now seldom met with. This, of course, is a source of increased profit to the brewer, as it enables him to turn over his capital more rapidly, and saves the risk and expense attendant on long storage.

7. RIPENING:--After a period varying from one to twelve months or longer, according to the nature of the brewing, and the condition of the cellar, the liquor will have become fine, and sufficiently mature for use. During this period the casks, &c., should be occasionally examined to see that there is no leakage, and to open the vent-holes, should any oozings appear at the joints. As equable a temperature as possible should be maintained in the cellar, by ventilation, on the one hand, and the employment of artificial heat on the other, as circ.u.mstances and seasonal changes may render necessary.

8. FINING or CLARIFYING:--Beer which has been badly brewed or badly stored, or which from other causes may be thick or muddy, requires clarifying by artificial means. For a barrel about 1 to 1-1/2 pint of brewer's finings (isingla.s.s or fish-gelatin dissolved in sour beer) is put into a bucket, and some of the beer being gradually added, the whole is violently agitated with a whisk until a frothy head is formed. The mixture is then thrown into the cask of beer, and well 'rummaged up,' after which the bung is replaced, and the liquor allowed to repose for a week or ten days.

Sometimes the above method is found to fail with weak and bad-conditioned beer. When such is the case, the addition of a teaspoonful of sulphuric acid, or a table-spoonful of powdered catechu (previously dissolved in 1/2 a pint of boiling water), followed by agitation for a quarter of an hour, will generally cause the 'finings' to clarify the liquor; 2 or 3 oz. of tincture of catechu (mixed with a little water) may be used in the same way. A handful of hops, previously boiled for five minutes in a little of the beer, and then added to the barrel, and the whole allowed to stand for a few days, before proceeding to clarify it, will generally have a similar effect, and cause the 'finings' to act with certainty. It is the absence of the proper quant.i.ty of astringent matter in beer that usually renders them ineffective.

M. Brescius employs tannin for the clarification of beer. To 1000 litres of beer he adds 140 grains of tannin dissolved in 3/4 of a litre of water, which is thoroughly stirred up. After three or four days he adds one litre of isingla.s.s or two of gelatin in the proportion of 1 kilo. to 100 litres.

The complete clarification requires about eight days.

_Gen. commentary._ The preceding is a concise account of all the essential operations of the system of brewing at present practised in this country.

On the large scale, extensive and costly apparatus and machinery are employed for the purpose. On the small scale, various modifications, of a minor character, or the several processes herein detailed, are frequently adopted according to the circ.u.mstances or ingenuity of the operator. The principles and practice of brewing beer are, however, essentially the same under all the conditions here referred to. In Scotland, only one mash is made, and that at a temperature of about 180 Fahr., with one third of the quant.i.ty of the water required for the brewing. The 'mash-tun' is then covered up for about half an hour, when the wort is drawn off, and the operation of 'sparging' begun. This operation is continued until the density of the mixed worts becomes adapted to produce the quality of the ale then under process of manufacture. The 'gyle-tun' (fermenting-tun) is set at from 50 to 60 Fahr., the fermentation being continued slowly for fifteen to twenty days; and the ale is not 'cleansed' before the degree of attenuation falls to about 1/2 lb. per day, and not more than one fourth of the original gravity of the wort remains. Scotch ale is justly celebrated for its superior quality. Its usual original gravity is from 34 to 45 lbs. per barrel.

In Bavaria, a country remarkable for the excellence of its beer, the wort is made to ferment at a low temperature, until all the substances which favour acetification have been rendered insoluble, and have separated from the liquor. The fermentation is conducted in wide, open, shallow vessels, which afford free and unlimited access to atmospheric oxygen; and this in a situation where the temperature does not exceed 45 to 60 Fahr.

A separation of the nitrogenous const.i.tuents thus takes place simultaneously on the surface, and within the whole body of the liquid.

The clearing of the fluid is the sign by which it is known that these matters have separated. The fermentation usually occupies three or four weeks, and is conducted during the cooler portion of the year only, and in a situation removed as much as possible from the influence of atmospherical changes of temperature. The sedimentary yeast (unterhefe), and not the surface yeast (oberhefe), of the Bavarian fermenting backs is employed.

The beers of England and France, as well as most of those of Germany, become gradually sour by contact with the air. This defect, as observed by Liebig, does not belong to the beers of Bavaria, which may be preserved, at pleasure, in half-full casks, as well as in full ones, without suffering any material alteration. This precious quality must be ascribed to the peculiar process employed for fermenting the wort, called by the German chemists 'untergahrung,' or fermentation from below; and which "has solved one of the finest theoretical problems that had long taxed the ingenuity and patience of both the scientific and practical brewer."

(Liebig.)

The 'Comptes Rendus,' lxxvii, 1140-1148, contains a paper by M. Pasteur on the manufacture of an 'unalterable beer.' In this communication he states that the liability of beer to turn sour, ropy, &c., is due to the presence of special ferments derived from the air, and from the materials used. By boiling the infusion of malt and hops, cooling out of contact with air, and fermenting with pure yeast[232] in vessels to which only carbonic acid or pure air is admitted, a beer is produced of superior quality, which may be preserved without trouble for any time. Even a partial adoption of these precautions is attended with valuable results. In preparing pure yeast to start with, the author makes use of the fact that oxygen favours the growth of true yeast, but hinders the propagation of the other ferments. Pure yeast being obtained, the beer is afterwards fermented in an atmosphere nearly dest.i.tute of oxygen, as its quality is thereby improved. Pure yeast when kept in pure air undergoes no change, even at summer temperature. The _mycoderma vini_ does not, as the author once thought, become changed into beer-yeast on submersion in a nutritive fluid; under these circ.u.mstances it acts as an alcoholic ferment, but does not propagate itself.

[Footnote 232: M. Pasteur does not state how this is to be obtained.]

"In the ordinary fermentation of grape-juice and worts these liquids do not furnish a quant.i.ty of alcohol equivalent to the sugar which they contain; and this because a certain portion of the sugar serves for the oxidation of the gluten, and is not transformed like the rest. But wherever the liquor has arrived at the second period of transformation, the product in alcohol ought to be equivalent to the quant.i.ty of sugar present, as actually happens in all fermentations (sedimentary) which are not accompanied with a formation, but a disappearance of the yeast.

According to Dr Ure, worts furnish, in the Bavarian breweries, from 10% to 20% more alcohol than they do by the ordinary process of fermentation (obergahrung), or that excited by the use of 'oberhefe' or top-yeast."

East-India Ale or Pale Ale, for exportation, is brewed from worts of a sp.

gr. of from 1063 to 1070. For the best varieties, 15 to 16 lbs. of the finest East Kent hops are used to every quarter of pure malt. The pale ale or bitter beer of the publicans is commonly a very weak liquor (mere table beer), highly bittered with the hop, and too often with qua.s.sia, wormwood, and other still more objectionable substances. The process now adopted by the great brewers of pale ale at Burton-on-Trent combines all the most admirable points of both the Bavarian and Scotch systems of brewing.

Berlin White ale or Pale beer is brewed from wheat-malt mixed with about 1/6th part of barley-malt, the 'wort' being boiled with hops, 1/2 lb. to the bushel, and slightly fermented with 'top-yeast,' at a rather higher temperature.

The desire of evading the duty led to the discovery of its being only necessary to employ 1/3rd, or less, of the grain, in the form of malt; this portion being sufficient to convert into sugar, in the process of mashing, the starch of the unmalted grain forming the other part. This plan answers well when the wort is merely intended for the production of 'grain spirit,' but beer so made is insipid and inferior in quality to that brewed wholly of malt. Inferior kinds of beer have also been made from other ingredients than barley-malt, among which may be named the grain of the cheaper cereals, bran, potatoes, turnips, beet-root, carrots, parsnips, pea-sh.e.l.ls, and other vegetable substances rich in starch and sugar, all of which will produce beer by being mashed with water in the common way, with about 9% or 10% of barley-malt.