Finings (part two)

Now here's an important question: when do you fine?

An obvious place to add finings would be in the racking tank. As that would be a good way of making sure they were mixed evenly through all the beer. But, for various reasons, Faulkner wasn't keen on that. Instead, he preferred to add them to the cask. And that could happen either in the brewery or in the pub cellar.

Nowadays, I don't think there are any brewers who would trust pub landlords to fine their beer correctly. In the past, it seems to have been commonplace.

"It may be asked, If the tank is unsuitable for fining operations, where should it be accomplished ? Now, I have spoken, among other matters, of London beers that are fined by the publican, and, in many large towns, more especially in the North of England, it is quite customary for the brewer to supply finings to the publican, which he applies as he thinks proper.

The London manipulation is, however, unique in its way, the finings practically being thrown out of the bung-hole on account of the beer itself being supplied to the houses in very fresh, and what I may term yeasty, condition; while, in the other towns mentioned, the beer is supplied very clean, and the finings go directly to the bottom, the cask being bunged tightly up."
"The Theory and Practice of Modern Brewing" by Frank Faulkner, 1888, pages 290-291.

That's something I've never heard before: that London beer was delivered in a very lively condition. I always thought that finings took stuff to the bottom of the cask, not expel it through the bunghole.

I wonder exactly what he means by "very clean". Does that mean it was pretty bright and free of yeast?

Finings

Another important process was fining. And another one which has a surprisingly long history. The use of isinglass going back until at least to the 17th century. Though, even after its introduction, beer which underwent a long secondary fermentation was still expected to drop bright without finings.

"In coming to the question of fining, we are face to face with a matter requiring thorough investigation, for the use of an artificial fining material has simply revolutionised brewing operations; for whereas some few years ago public taste was in favour of aged beer, and as very lengthy storage of the unfined beer in bulk was necessary to ensure brightness, a vast amount of capital was consequently locked up during such period, while, at the present time, I should say two-thirds of the beer produced in England is consumed within a month of its production, forced into a condition of brightness by artificial means."
"The Theory and Practice of Modern Brewing" by Frank Faulkner, 1888, page 229.

It's a sign of the decline in the popularity of aged beer that two-thirds of beer was sold withing a couple of weeks. At the start of the 19th century, the situation was very different. Especially with the popularity of Porter.

Isinglass, it seems, was superior to other fining agents. Which I guess is why it's still being used.

 "So far as I remember, the introduction of isinglass as a fining material was the primary cause of the complete change in modus operandi spoken of, for all previous artificial methods, such as the use of silver sand, alum, and so forth, were singularly ineffectual by comparison, and the beer so clarified was not calculated to impress people by its degree of brilliancy and early palate character; for I know of nothing that interferes so much with the delicate flavour of beer, especially of that of only moderate gravity, as the semi-cloudiness which means a very intimate kind of connection existing between the amorphous matter and yeast in suspension in the weak alcoholic fluid."
"The Theory and Practice of Modern Brewing" by Frank Faulkner, 1888, page 229.

It seems that the use of finings was important for the development of Mild Ale.

". . . it was only after the introduction of gelatine as a combined chemical and mechanical fining agent that brilliancy was attainable, and a mild beer produced fit for consumption almost directly after fermentation was complete."
"The Theory and Practice of Modern Brewing" by Frank Faulkner, 1888, page 230.

Which pretty much describes the way 20th-century Mild was handled.

Cask beer in the 1950’s – Fining

The fun really never ends, does it? Or does it never start?

This time we’re revisiting fining. Another topic that gets Jeffery all hot under the collar. Especially over-enthusiastic fining.

“Fining
Most breweries prefer to send their beers out already fined, although a few brewers still consider that better and more regular results can be obtained if the beers are fined down about 24 hours after delivery into the cellar. Both beer and finings will then have become acclimatized to the temperature of the cellar. First, however, let it be stated that no attempt should be made to fine down beers which show any degree of fermentation. Not only will such a procedure mean useless loss of finings, but it will probably intensify the trouble. If the beer is reasonably quiet, it will be necessary first to remove some of the contents of the cask and make room for the finings. With part of this surplus, thoroughly mix the required quantity of finings (usually one pint per barrel of 36 gallons for running mild beers, and one and a half pints for pale ale) before adding to the cask. If it is then possible, give the cask a good rolling. This process is particularly necessary with dry hopped pale ales, as the hops will assist the action of the finings. If rolling is impossible for want of room, then the contents of the cask must be well roused right from the bottom. It is hopeless and useless to add to beer finings which have not been well mixed with a proportion of beer before adding. In their heavy and undiluted state they will immediately drop to the bottom without fulfilling their purpose. Should it be necessary at any time to re-fine beer, it can often be achieved by adding diluted finings to the extent of half a pint per barrel, and rousing in at the top of the cask only. If this procedure is found to be ineffective, the only remedy is to add the additional finings and roll the cask completely over again several times.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, pages 256 - 257.

I wonder why Bitter required more finings than Mild? Especially if the dry hops it contained helped the process. If you fined in the brewery, there’d be no real need to roll the casks specifically around. That would happen automatically during the delivery process.

Do any breweries let their beer be fined in the pub today? I doubt it. Let’s check to see what Briggs recommends:

"Settling controls yeast count but to aid this process, finings are used (Chapter 15). Isinglass finings are added at the rate of 1 to 4 pints/imp. brl (0.36±1.44 l/hl). These finings can be added in the racking tank or at any point up to when the beer is dispensed. The usual point of addition is at rack with perhaps a prior addition in the racking tank. In any event the beer will require from 12-48 h and possibly up to 72 h to fine and settle before it is sold. The fining of cask beer is one of the most difficult of all brewery operations to control consistently. Often brewers experience periods of poor fining which are difficult to explain. Isinglass finings bear a positive charge because of the rich collagen content and interact with the negative charge on the yeast cell wall. In most circumstances this interaction is sufficient to achieve effective clarity.”
"Brewing Science and Practice" by Dennis E. Briggs, Chris A. Boulton, Peter A. Brookes and Roger Stevens, 2000, page 807.

Sounds like Briggs prefers fining in the racking back or to the barrel at filling time. Though he does admit that fining could take place later. Intriguing that he recommends significantly more finings, up to four pints per imperial barrel, as opposed to Jeffery’s one to one and a half pints.

Isinglass finings alone aren’t always enough:

“Some beers, sometimes will not fine with isinglass alone. The yeast may have a too low negative charge or the concentration may be too high (say >2 million cells/ml), or there may be too high a concentration of positively charged colloids in the beer. In this situation auxiliary finings derived from alginates, carrageenan or silicic acid, and having a negative charge, can be added to the beer before isinglass finings to precipitate the positively charged colloids (Vickers and Ballard, 1974). An effective method is often to add the auxiliary finings in the racking tank and separate the flocs thus formed in this vessel and then to add the isinglass at the rack of the beer. Priming sugars are also added to some beers at this stage. These are normally solutions at 1150º Sacch (37º) and are added at rates of 1 to 5 pints/barrel (0.35±1.75 l/hl). The priming sugar provides a small quantity of fermentable carbohydrate (often sucrose) to assist the yeast to achieve effective secondary fermentation in the cask."
"Brewing Science and Practice" by Dennis E. Briggs, Chris A. Boulton, Peter A. Brookes and Roger Stevens, 2000, pages 807 - 808.

Sounds to me as if something isn’t right in the brewing process if isinglass won’t work by itself. Most of the sludge should be gone before the beer hits the racking tank.

I thought I’d leave in the bit about primings. Those rates seem to tally with the practice at Barclay Perkins.

Just in case you weren’t listening the first time, Jeffery repeats his warnings about fining fermenting beer and using too many finings:

“We must once again impress upon our readers a rule which should always be observed. Never add finings to a cask of beer which shows the slightest degree of fermentation. Such a procedure is a waste of finings.

Before leaving the subject of fining, we should also like to stress the fallacy of using more finings than are really needed. Any excess deprives the beer both of character and condition.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, page 257.

Have you got that yet? Don’t fine fermenting beer and don’t fine too much.

Secondary fermentation next. But I bet you’re really waiting for ullage. Lovely word that, ullage.

Cask beer in the 1950’s – finings

This is such fun. And just wait until we get to the next chapter which deals with handling cask beer in the pub. That’s a real eye-opener.

Let’s get started.

“Fining
The composition of finings has already been described, also reason why they are used. Their aim is to effect as rapidly as possible the condition of clarity which, provided the beer has been properly brewed, would doubtless have resulted spontaneously in the long run. It remains now to deal with the quantity of finings which should be used, and the best time at which to use it.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, page 246.

So they are a shortcut to clarity, really. Stock Pale Ales in the 19th century weren’t usually fined but expected to drop crystal clear during the long maturation process. I wish some modern brewers would take note that unfined doesn’t mean that the beer has to look like mud in the glass.

This is an interesting point:

“It is hardly necessary to point out that the addition of finings, besides increasing the sludge and bottoms, takes something out of the beer and decreases the palate-fullness. Wherever possible, especially in the case of stock ales and beers for bottling, the use of finings should be dispensed with. Where necessary, as is always the case with running ales, the least possible quantity should be used which is compatible with satisfactory results. One pint of well-made finings per barrel should be the maximum quantity used for running beers, one and a half pints for pale ales, where the finings are called upon to do more work on account of the large amount of hops present in the cask. Even these quantities may be reduced where the finings are made from the best Saigon leaf. This leaf undoubtedly has very strong fining powers. Curiously enough, these finings are rather deceptive in appearance. They seem to be weak and unduly thin. The appearance is deceptive, however, and a proof that apparent strength as revealed by viscosity is not always reliable.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, page 247.

So maybe the anti-finings brigade do have a point. Finings thin a beer out. Still doesn’t mean I want to drink a pint of sludge, though.

The large amount of hops in Pale Ales would be the dry hops. Though surely a running Bitter would also be dry hopped. He seems to be assuming that running beers were always Mild, which wasn’t usually dry hopped.

Now the tricky question or when to add finings:

“The question of when most suitably to add finings is a debatable one. At one time opinion was in favour of fining in the houses, but with the quicker deliveries that are now possible with modern transport, the major objection to fining in the brewery is removed. If finings are added just prior to despatch from the brewery, the beer will fine satisfactorily within a few hours of its receipt at the cellar of the house. When fining in the houses was the rule, it was sometimes found that better fining was achieved when both beers and finings had been delivered together and stored in the same cellar not less than 24 hours previous to the beer being fined down. Both beers and finings had become acclimatized to the surrounding temperatures, and the action of the finings was more regular and efficient than was the case when the beers were fined down at the brewery. Few breweries now fine in the houses, however.

The advantage of fining at the brewery lies in the knowledge that the job has been done properly. Also, a certain quantity of beer is saved per cask, which in some breweries means quite a large barrelage per annum. Against this might be placed the poor results which could be obtained due to exposure of the fined beer to many variations in temperature in the course of delivery.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, page 247.

So fining had first mostly been done in pubs, but had shifted to the brewery. I’m surprised at fining only taking a few hours after delivery. I’d have thought 24 hours was more like it. Though I know that the Nottingham breweries’ beer used to drop bright pretty quickly.

I can understand why brewers wanted to do the fining themselves. They had more control over what went on and removed a possibility of the landlord cocking it up. You’ll have noticed that the author clearly doesn’t trust publicans to handle beer properly.

There were times when fining needed to be done earlier, even before racking:

“Sometimes one hears of fining taking place in the racking back. It is a practice of which we  are not in favour unless the fermentation has been very sluggish, and the emission of yeast unsatisfactory. Of course, if the beer is yeast-bitten, and it is essential to avoid the introduction to the cask of a large amount of undesirable sludge and sediment, part fining in the racking square is not only advisable, but necessary.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, pages 247 - 248.

Only to be done when the fermentation hadn’t gone well and the beer still contained large amounts of yeast.

Next time it gets really exciting when we learn what went on in the pub.

Bottling in 1901 - other factors affecting flavour (continued)

Still no end in sight to my look - with the help of the Journal of the Institute of Brewing - at bottling at the start of the 20th century.

We're now longer at substances added to beer after the completion of primary fermentation.

"G. Priming, finings, antiseptics.

Each of these may have a more or less marked influence on the flavour of the ale, and I know that they are occasionally accountable for unpleasant flavoured ales.

The distinct flavour of many of the sugars specially recommended for priming is, more especially in the case of stout, a feature of considerable importance.

Finings made in the old-fashioned way with sour beer may and do seriously affect the flavour of ale in which they are used. The various sulphites used as antiseptics may almost invariably be detected by a skilled palate for some days after they are first added, but fortunately their action is only transient in this respect, and it is quite the exception to find a beer properly matured having any appreciable flavour of sulphites.

More powerful antiseptics, such as salicylic acid, are, I am glad to say, condemned by the county authorities, so are but rarely used, for although there is no evidence that such a small amount as two or three grains per gallon has any harmful effect when taken into the system— in fact, in cases of rheumatism it might be distinctly beneficial—there is always the risk of larger amounts being introduced, and if a man must take drugs he prefers to have them administered by a doctor. I may say that I have seen salicylic acid tried in the full dose of half an ounce to the barrel in badly brewed ales, and these beers have not kept any the better, and have developed a flavour infinitely more
objectionable than when not so treated.

The use of sanitas, formalin, and silico-fluorides is I consider subject to serious objections, the first two having decidedly objectionable flavours, and the latter have recently been proved to be poisonous.
Journal of the Federated Institutes of Brewing, Volume 7, Issue 2, March-April 1901, pages 201 - 202.

Primings - a high gravity sugar solution added at racking time to promote fermentation in the cask - were gaining popularity at the end of the 19th century. They helped to bring cask Running Beers into condition quickly.

Letting the primary fermentation run its course then adding more fermentable material was an easier and more reliable way of quickly producing well-conditioned cask beer. Ttrying to guess when there was just enough fermentable material left for secondary conditioning was much trickier and could lead to beer that either wasn't properly carbonated or too lively. The same was also true of bottled beer, if it were left unpasteurisaed and so still contained active yeast.

I'm intrigued  that Stout is specifically singled oput as a type of beer where primings were particularly necessary. If you've been reading this blog for long, you'll know that Guinness had their own particular way of fining. They used high-gravity wort called "heading" instead of a sugar solution. A sort of Reinheitsgebot version of priming. Or an Irish take on kräusening.

Which reminds me that I've some good stuff lined up about American Ale brewing from around this period and the use of kräusening. I should be getting around to it in a few days.

I've always read with horror the descriptions in old brewing textxs of how to dissolve isinglass in sour beer to make finings. Sounds like a great way to infect your beer.

I'm pretty sure salicylic acid was quite commonly used as a preservative. It was one of the things American health authorities looked for when they analysed beer. And they regurlarly detected it. It sounds a pretty useless additive: it could be dangerous to health, adversely affected the flavour of the beer and didn't really help preserve beer. The other preseervatives mentioned sound even scarier.

"H. Alcohol and carbonic acid.

The characteristic effect on the palate produced by these two normal ingredients of all beers is not perhaps what people usually mean by flavour, but they are so closely associated with it, and so markedly influence the power of distinguishing the true flavour, that I think they must be included here; more especially carbonic acid, as it is really the most important factor in producing the difference in flavour of bottled and draught ales.

I would in this connection draw your attention to the difference between the effect on the palate of carbonic acid gas held in true solution in a liquid, as compared with the same amount of gas merely mixed with the liquid, as it is this difference which very materially causes old bottled beer to taste so much nicer than newly bottled ales, even when the latter are highly charged with carbonic acid gas."
Journal of the Federated Institutes of Brewing, Volume 7, Issue 2, March-April 1901, page 202.

The amount of carbonic acid gas - or CO2 as we call it - is certainly the one of the biggest differences between bottled and draught beer. Or perhaps I should say cask beer, as artificially-carbonated keg beer can have CO2 levels similar to bottled beer.

The second paragraph brings up a topic that has puzzled me for a long while: can CO2 be held by beer in different ways. I've often seen it claimed that in a naturally-conditioned beer smaller CO2 bubbles form than in a force-carbonated beer. The counter-argument is that CO2 is just CO2 and there's no difference between that formed naturally in the beer by fermentation and that added externally.

I've been reluctant to take a position on this, because I've heard such conflicting opinions and I don't understand the science personally. But experienced brewers have assured me that there is a difference. Is it possible to mix beer and CO2 without the latter fully dissolving? I've no idea. I'll welcome comments from the more scietifically educated amongst you.

This article is really jam-packed with good information. And we're not finished yet. Next we'll be looking at the effect of kilning temperatures and mash heats on the fermentability of wort.

Old Ale in the 1790's

I've still not forked out on a copy of Richardson's "Philosophical Principles of the Science of Brewing.". I'm making do with Booth's copy still. I hope he transcribed it accurately.

This time it's Old Ale that's being described:

"Richardson's Instructions continued.

Art. II.—For Old Ale, or such as is to be long kept.

§ 1.—Heat of the Liquor.

As purity is not immediately required in this sort of ale, the first mashing heat should be as low as practicable; that is, so as just to avoid acidity in the wort, which is apt to be produced by a very low heat of the liquor. Hence 160º or 165º may be the first heat, and from 10º to 15º may be added for the second, if there be but two mashes, and 10º each if there be three. Thus if the first heat be 160º, and you find no tendency to acidity in the last running of the worts, then these rules may be observed; but if there should be a little acidity discernible, it were advisable to make the increase 4° or 5° more for the subsequent mashes, and on brewing another gyle of the same sort, from the same malt, it were best to begin at 165°, and then observe these rules for the next mashings.

§ 2.—Time of Infusion.

If the heat of the liquor be very low, the time of infusion should be somewhat less than that allowed for mild ale. Therefore, two, or two and a half hours may be allowed for the first mash, and one hour for each of the rest.

§ 3.—Quantity of Hops, and time of boiling.

The general rule for hops is one pound per bushel of malt; but if it be intended that the ale should retain its mildness to a very distant period (which by the bye is to answer a very useless purpose), a larger portion of hops must be used, agreeably to the intention of the brewer.

The boiling is regulated by time, as the nicety of flavour is not such a requisite in this as in mild ale. In two worts the boiling may be from an hour to an hour and a half for the first, and two or two and a half hours for the second; in three worts, the first may boil one hour, the second an hour and a half, and the last two or two and a half hours.

§ 4.—Quantity of Yeast, and mode of Fermentation.

If the first heat of fermentation be not below 60º, and the gravity not much more than thirty pounds, provided the air be temperate, the quantity of yeast must be from two to two and a half pounds per barrel, applied in the manner as directed for mild ale. If the heat be lower, the specific gravity more, or the heat of the atmosphere less, the quantity of yeast must be increased in proportion; in doing of which, no great inconvenience can arise from applying a few pounds too much, but it may occasion an imperfect fermentation if there be a few pounds too little.

The heat of the fermentation should not exceed 75º at the highest, but rest between that and 70º, though the nearer 75° the better will be the flavour of the ale at an early period; and as a low heat of mashing is conducive to a great increase in the heat of fermentation, it will thence be evident that the fermentation for ale, whose average gravity is thirty pounds, must begin at or below 60 , and the precautions before recommended respecting the yeast, must be particularly attended to. The mode of conducting the fermentation, and the criterion for cleansing, being the same with those directed for mild ale, a repetition here would be superfluous.

I, however, recommend a more strict adherence to the rules for cleansing, before inculcated in this process, than in that for mild ale, because the first heat being lower, a greater time is necessary to bring the fermentation to perfection, and secure the future good flavour of the ale. It may be here observed that this sort will generally require finings."
"The art of brewing" by David Booth, 1829, pages 43 - 44. (Copy of text from Richardson's "Philosophical Principles of the Science of Brewing." 1798.)

One important point before we continue. It's about Ale, Mild and Old. Old Ale was not simply Mild Ale that had been aged. Old Ale was brewed to be aged, While it might well have used the same basic recipe as a Mild Ale, it would have been tweaked - principally in the quantity of hops used - to help it keeping qualities. Just thought I'd make that crystal clear.

Here there's a difference in the process for the Old Ale. Specifically, it's mashed cooler. I can't think of an reason for doing that myself, but I'm sure there must be one. The mashing scheme, with two or three separate mashes, is very 18th century. Though, in England, brewers continued to mash several times well into the 19th century. And yes, I do have an example. Two, in fact. a XXX and a XXXK from Truman from 1831. XXX being a Mild Ale and XXXK a Stock, or Old Ale. Let's take a look:

	XXX	XXX	XXXK
1st mash	177º	178º	176.5º
2nd mash	184º	185º	185º
3rd mash	183º

Doesn't look to me as if the Keeping version was mashed any differently. And neither is anything like as cool as Richardson's recommendation.

A pound of hops per bushel is 8lbs per quarter. How does that compare with some real beers? In 1837, Whitbread's KXXX was hopped at 7.64 lbs per barrel, KXXXX at 8.06 lbs. About exactly the same. The Truman XXX from above was hopped at 8 lbs per quarter, the XXXK at 14 lbs per quarter. Rather more than Richardson suggests.

The fermentation temperatures look about right: pitching at around 60º F and letting the temperature rise no higher than about 75º F. That's very similar to how Whitbread fermented their Ales in the 1830's. Their Porters, on the other hand, they fermented warmer: pitched at 63-64º F, rising to about 80º F.

30 pounds gravity is 1083º. Which, in the 1830's, would have been an XX Ale, on the scale of 1 to 4 X's. Not particularly strong.

I was surprised that finings were needed. I thought one of the points of ageing beer was to allow it to drop bright spontaneously.

Sludge

Sludge. Not something I'd ever thought about much. Thankfully someone else has.

The particular type of sludge being discussed here (because there are several different types) is the stuff found in the bottom of fermentation vessels:

"This fermenting-tun sludge not only contains dangerous yeasts but a great deal of amorphous matter and bacteria. Indeed the yeast in a fermenting-vessel may be regarded as a fining agent acting both upwards and downwards. The rising heads take out with them a large amount of amorphous matter and some bacteria, but a good deal of the amorphous matter and the greater part of the bacteria are carried to the bottom with the yeasty deposit. The deposit, indeed, is as compact a compound of brewer's pests as could well be conceived, and the brewer who allows it to pass into his beers when there is not the least occasion to do so, pretty well deserves the punishment that some day or other will follow his negligence.

When settling-vessels are used, a similar sludge settles out at the bottom of these vessels, and the same care should he taken to retain it in these vessels as is so necessary in the case of fermenting-vessels. The beer associated with the sludge, whether in the fermenting- or settling-vessel, need not be wasted. It should be taken to the presses, and the clear beer mixed off in small proportions with that particular beer for which there is the most assured quick consumption, preferably black beer. If there be any difficulty about effecting a separation in the presses, that difficulty will generally be removed by adding finings to the sludge and beer about twelve hours before pressing. If there are no presses, bags answer equally well.

A case which came before me a few years ago bears very closely upon what I have been saying, although applying rather to the sludge which forms in beer storing vessels than to that in fermenting or settling plant, but the principle is the same.

A brewer was in the habit of bottling a light pale ale himself, and the contents of each storing-vessel were, when bottled, stacked and kept separate. In all cases the beer contained in the bottles on the top layers of the stacks showed floating particles (apparently of finings), while the rest was perfectly free from any such defect. It seemed inconceivable that the mere fact of certain bottles lying above the rest should produce a precipitation exclusive to those top-most layers ; but whatever was tried the result was the same.. The beers were then brought to me, and I found that the floating particle in the top layer beer were not finings at all, but agglomerations of wild yeast, and this led me to suppose (as indeed was the case) that these top layer beers representing the bottom strata of beer in the storing vessels had got practically the whole of the wild yeast sediment which had collected in the storage vessels, whilst the lower layers of bottles which were taken from the upper strata of beer in bulk got practically none of it."
"Journal of the Federated Institutes of Brewing, Volume 1, 1895", pages 493-494.

A cautionary tale. Watch out for sludge, brewers. You never know what might be in it.

Fermenting, maturing and serving Porter in 1813

You'd think March was Porter month from the amount I've posted on the topic. In reality, every month is Porter month here. You might have guessed from the title that this post discusses the steps from fermentation to serving.

The stuff about the temperature sort of tallies with what I see in brewing records. In the 1820's, Barclay Perkins were pitching at 63º to 67º F after which the temperature rose to around 80º F. Though the stronger Stouts were pitched much lower, at 58º to 59º F. By the end of the 19th century, their pitching temperatures were down to 60º to 62º F.

"The different worts after boiling are spread out thin in the coolers, and their temperature brought down to between 60 and 70 degrees, at which all the three worts are mixed together in a great vessel called the guile tun or square, where yest being put to it the liquor is fermented. The temperature at which the wort is set to working in the square, and the heat at which the several mashes are made, have greater influence than any other circumstances upon the quality of the beer. The greater the working heat is, the more rapidly the fermentation proceeds : therefore in summer, when the natural heat of the air is such that the working will advance perhaps more rapidly than the brewer wishes, he counteracts this by cooling the wort down as low as possible : on the other hand, in cold weather the fermentation must be encouraged by commencing it at a greater temperature : in general it may be stated to be between 60 and 70 degrees, at the discretion of the brewer, and in some degree regulated by the kind of porter he wishes to produce, and the malt from which he has extracted his wort. The fermentation is continued in the square as long as the head of yest which floats upon it continues to increase in depth ; but when the head shews signs of diminution the liquor is fit for cleansing. This is putting it into a great number of small casks, which, by dividing the beer into small quantities, lowers its temperature and tends to check the fermentation. The same end is also attained by causing the yest to flow off as fast as it is produced, and keeping the casks always filled up as they diminish by working, to leave no room for a head of yest to gather upon the surface of the beer. After the fermentation is concluded the beer is put into immense casks called store vats, where it is kept till wanted for sale. By keeping it begins to clear itself, and grow fine ; but it is seldom kept long enough to become perfectly so. It is when wanted drawn off from the store vats into casks, and then sent away ; and the consumer puts into the cask a small quantity of fining, sent out with the porter by the brewer, who calls it in the rough when his liquor requires fining.

The finings are made of isinglass dissolved in sour beer brewed from the wort of the fourth mash, or sour beer obtained from the waste of any of the processes. A small quantity of this fining beer being put into the cask precipitates the minute fecula, and soon renders the liquor quite fine. The flavour of the draught porter in London is almost universally obtained by compounding two kinds, the due admixture of which is palatable, though neither are good alone. One is mild, and the other stale porter; the former is that which has been lately brewed, and has rather a bitter mawkish flavour ; the latter has been kept longer, and is in some degree acid. This mixture the publican adapts to the taste of his several customers ; he effects the proportion of mixture very readily by means of the Beer Pumps, described under that article (see pl. 24). These will be found to have four pumps, but only three spouts, because two of the pumps throw out at the same spout. One of these two pumps draws mild, and the other the stale Porter; and the publican, by dextrously changing his hold to the next handle works, either pump, and draws both kinds of beer at the same spout; and an indifferent observer supposes that since it all comes from one spout it is entire butt beer, as the publican professes over his door, and which vulgar prejudice has decided to be the only good porter, though the difference is not easily distinguished."
“Pantologia: A new cyclopaedia Vol IX”, 1813, (doesn’t have page numbers)

Using sour beer for preparing finings has one pretty obvious disadvantage: it's a good way of introducing an infection. You can't help wondering how often such finings buggered the beer in addition to clearing it. Later in the century brewers moved over to using other dilute acids in which to dissolve finings.

I'm not sure what to make of the final section about the strange beer engines. Is it to be believed? Was this really common practice? Certainly a couple of decades later brewers were advised not to send out their Porter mild, but to always blend it themselves. Mostly to reduce the possibility of the publican adulterating the beer.

And the flavour descriptions: mild Porter was "bitter mawkish" and stale Porter "in some degree acid". I think I can understand what the second means. But the first? The word mawkish has fallen into disuse and doesn't really say a lot to me.

That might be it (at least for a day or two) about Porter. But you never know, I might find something else I just have to share.

Conditioning in the cask

It seems that breweries trying to skip proper conditioning in of their beer in the pub is nothing new.

This 1894 advert from Overton & Gibbon makes clear that they weren't taking shortcuts:

"Nothing artificial is used in these Ales in the shape of Finings (in order to produce early brilliancy), consequently the Ales will require about three days to become spontaneously bright. THESE ALES WILL NEVER ACIDIFY."

There really isn't anything new under the sun, is there? It sounds depressingly similar to the modern practice of racking beer pretty much bright into casks so it can be sold almost as soon as it hits the cellar floor.