More searching in the JIB archives brought up an article from 1895 titled Brewing in Belgium and Belgian beers by G M Johnson. It's fascinating stuff, and an excellent way of doing a long blog post: get someone else to write most of it.
I've cut out some bits and put some commentary in, hope it all makes sense.
"Out of a total of about 2,700 breweries, fully 2,500 practice the system of manufacture that I will presently describe [top fermentation], whereas there are only about 25 bottom fermentation [lager] breweries in the country. These, although they mostly belong to Belgians, have been bought, I may almost say bodily, from Germay, and put up in Belgium with a complete staff of German managers, brewmasters, and workmen. They draw too the great bulk of their supplies from Germany. Besides the top and bottom fermentation breweries, there are also some 200 breweries where so-called spontaneous fermentation is practiced. In these breweries the worts, produced from a mixture of raw wheat and barley malt, are run into casks of about the capacity of hogsheads, no yeast being added, and are left to ferment. The fermentation takes about two years. The beer is then generally left for another year to fine and mellow. The fermentation is principally caused by the yeast and bacteria deposited during previous fermentations conducted in the cask. Moreover, the casks are only very superficially cleaned, and never steamed. This process of manufacture is probably now what it has been for centuries past, and, although is it eminently a wasteful process, both as regards the brewing process proper and the fermentation process, nobody dares try any experiments with it, as you have to wait three years for the result, generally to find that you have modified the character peculiar to the beer when brewed strictly on the old fashioned lines, and that you have dissatisfied the customers.”
It’s strange to think of a time when 200 lambic breweries were still going. What are there now? Does it even make double figures? Interesting to see he’s not convinced about “spontaneous” fermentation and instead puts it down to yeast and bacteria left over from previous fermentations. I have some doubts about spontaneous fermentation myself, and have heard that having wooden beams above the cooler so bug rich condensation can drip into the wort is important in lambic breweries.
“There are also in Belgium, besides the beers I have mentioned, several local beers, some of which are very peculiar. The white beer of Louvain and Peeterman of that district are well known to tourists. White beer is made from malt that is air-dried instead of being kilned, and its peculiar charm lies in it being thick. It is therefore best drunk new and in full fermentation. When by some mishap or other the yeast deposits, the waiter who serves you shakes up the bottle, or, if the beer be drawn from the cask, rolls it over or stirs it np with a stick until it has the desired consistency. It is not an easy matter for brewers who spend their lives at endeavouring to brew bright beer, to realise how very difficult it is to make a beer that will remain very thick. One point in the art is to throw a bushel or so of flour into the boiling copper, the object being to get plenty of free starch and sludge in the beer.”
This sounds a bit foul to me. Air dried malt would have been very pale, but surely even more sulphury than lager malt, and starch and sludge are not things I’d like to find in beer.
“You are doubtless aware that the great art of the Belgians is cheap production. Belgium's immense export trade in almost every conceivable commodity is maintained by cheapness. Everything that the people want, except perhaps sugar, is cheap, and beer is no exception to the rule. You will be, for instance, surprised to hear that an ordinary household beer of about 1040 gravity is sold to the private customer at less than 19s. a barrel, and that much public house beer, varying in gravity from 1025 to 1035, is sold at as low a figure as about 13s. a barrel. It is true that the beer duty is not so high as in England; it amounts in Belgium to 12s. per quarter of 336 lbs. or considerably less than half the English duty. Still that difference does not nearly account for the differences between the prices of beer that I have mentioned and prices of beers of equivalent gravity in England. The spontaneous beer of which I spoke just now weighs generally about 1063, or as much as Bass's Pale Ale for export. It is sold in Brussels at less than 28s. a barrel.”
Nowadays Belgium is known for its strong bottled beers amongst beer geeks, and some are happy to pay well over the odds to get hold of them. So I was even more surprised to see that previously Belgium was well known for it cheap and weak beer.
"As the market price of beer is so low, cheapness and economy have, of course, to be studied in every department of the brewery. In the first place, labour is cheap, and the Belgian brewer uses as little of it as possible. He keeps his brewery very dirty, for instance, although I am bound to say that, judging from some English breweries that it has been my privilege to visit, he has by no means the monopoly of dirt. Cheapness is such a rage with the Belgian brewer that it is not at all an uncommon thing to hear him say, when advised to keep his brewery cleaner, that cleaning costs money. Of course the more enlightened brewers have learned that cleanliness saves rather than costs money; and I am of opinion that if many breweries are still dirty, it is rather because cleaning costs trouble than because it costs money, and that when you have said that you have got to the bottom of the repugnance to cleanliness of the great bulk of humanity."
Keeping a brewery clean undoubtedly saves more money than it costs.
“Of course, if beer is to be produced cheaply, one of the essentials is that the first outlay should be as moderate as possible, so that interest on capital may be small in amount. Building materials and
plant are exceptionally cheap in Belgium, and a glance at the plan of a Belgian brewery that I have here will show you that, after all, no excessive outlay is necessary to build a brewery.
First, it is quite the exception to meet with any other than iron plant. The mash-tun, under-back, hop-back (when there is one), coolers, the pitching-tun, are all almost invariably of iron. The wort-mains are often made from drawn iron tubes. At one time, as in France at the present time, nearly all new plant was put up in galvanised iron, but lately there has been a law passed prohibiting its use, on account of the zinc, for any other vessels than those used for the storage of hot or cold water. In some breweries the coppers are of steel or sheet iron, but this metal is not so often used for beer coppers in Belgium as it is in some other countries.
It may interest you to know that I do not believe in iron plant. I am perfectly certain that it is not conducive to delicacy of flavour of the beers. It might be perfect if it did not rust, but in practice
there is always a little rusting somewhere, and such is especially the case in iron wort-mains.
With regard to wort-mains, I know a good many economical brewers who have these mains made of ordinary tin plate, and before the law changed I came across zinc piping occasionally. Wooden vessels lined with zinc were quite common.
Reverting to the question of iron plant, you invariably find in a brewery where much iron is used that the first head thrown up during fermentation is black, and there is sometimes so much iron put into solution that you will find in the collected yeast bits of black stuff as big or bigger than a pin's head, composed principally of a mixture of yeast and nitrogenous matter, tannin and iron, the result of the precipitation during fermentation of the organic salts of iron formed during the brewing process.”
This also sounds foul.
“In a Belgian brewery the mash-tun, as shown upon the plan, is more often than not destitute of a grist-case and mashing-machine, and the turning out of the sacks of grist into the tun is a job that makes endless dust, and undoubtedly contaminates the breweries. Underneath the mash-tun is an under-back, from whence the wort is pumped up into one or other of the coppers. Yon will notice that one copper is fitted with a chain stirrer. This very simple piece of plant enables the brewer to use raw grain. It also enables him to boil part of his mashes, a very necessary process in the production, of beers of low gravity. Next we have the ordinary brewing copper, which is very generally fitted with a strainer, thus doing away with the necessity of a hop-back. From the copper the wort is again let down into the under-back, and pumped up to the cooler, and from thence it runs down over the refrigerator into a tun where the yeast is added. As soon as the excise dip is taken, the wort, after being well roused, is run away to the fermenting-casks which you see on the plan. These casks are very rarely bigger than hogsheads, and in the majority of cases are neither more nor less than the trade casks themselves, varying from firkins upwards.”
“Given the brewery, it now remains to produce a cheap beer that shall taste full although it be of low gravity. The choice of materials is the first thing that influences the results. The Belgian brewer has learned by experience that winter barleys, or "escourgeons" as they are called in French, and of which I shall have more to say presently, are the only barleys that will enable the brewer to brew weak stock beers that will keep, the great majority of stock beers in Belgium not weighing more than 1050. I am also certain that the English brewer would do well to use these winter barleys for stock beers.
The beers remain full and are of wonderful stability, many brewers using no antiseptic whatever. Winter barleys also produce a weak running beer that will taste very full. Weak running beers made exclusively from spring barleys are apt to be thin and flat, and weak stock beers made from them are apt to get very knify. These defects of spring barleys can be remedied, to a certain extent, as far as running beers are concerned, by the use of a proportion of rice or maize, although beers so brewed will never quite come up to the winter barley beers. The use of raw wheat has also been pretty general in some districts for as long past as any one can remember, wheat producing a very full beer.”
The revered and venerable English barley variety Maris Otter is a Winter barley, though it only dates from the 1960s. Before that I think the preference of British brewers was for Spring barleys so it’s interesting to see Winter barleys being promoted in the 19th Century.
“The use of maize and rice has been introduced within the last 10 years, and at one time looked as if it was going to develop enormously. These cereals have, however, within the last two or three years, had to compete with malts made from Russian barley that costs only 16s. per quarter of 448 lbs. The malt made from such barley is, of course, much cheaper than rice or maize at present market prices.
Brewers, however, who look to the quality of their beers, still use raw grain. Moreover, it is a very curious and interesting fact that, provided the brewer knows what he is doing, very good running
beers indeed can be made from a mixture of, say, three-quarters or four-fifths of these very cheap Russian barley malts, and a quarter or one-fifth of raw rice or maize. Such a mixture produces the cheapest running beer possible, and, if the brewer be skilful, nobody would detect what it was made of. But, as I said just now, the fullest running beers of 1035 gravity, and in many districts of 1025
gravity, are made with winter barleys, with or without a mixture of raw grain.”
Using the cheapest ingredients to make very weak beer, that will never catch on.
The winter barley of which I speak is a six-rowed barley. I have two ears of it here for those who have not seen it. It grows only in certain districts. Ah far as the farmer is concerned, it possesses many advantages over spring barley. To begin with, it requires less manure. As it is sown in November and reaped late in July, it has ample time to draw its nutriment from the soil; it will consequently do with much less manure than spring barley which is sown in the spring and reaped in the early autumn. In the second place, the yield per acre is much greater than of spring barley. In the third place, it is much hardier, and is not inconvenienced by spring droughts, which so often thin a spring barley crop. Lastly, it commands a higher price in the market.
Six row barley is more associated with American barley now. In the UK we tend to have superior two row barley.
"The question naturally arises, why it in that two worts brewed under identical conditions, one from spring barley and one from winter barley, differ so essentially as to the resulting beer. It is found that the winter-barley wort attenuates loss, that it produces a much fuller beer, both when new and after storage, and, moreover, a beer that resists attacks by foreign ferments. The most plausible explanation is that the carbohydrate composition of the two worts differ."
Maris Otter is said to give a fuller malty flavour, though there are still those that think differences between barley varieties are not significant.
"Coming now to hops, there is nothing much to say that is not perfectly familiar to every brewer. Belgian brewers know that German hops communicate to the beer most keeping qualities, and
when they are not at prohibitive prices, these hops are very generally used in proportions varying with the degree of bitterness that the local trade will admit of."
So, German hops were widely regarded as the best.
"The main object of the Belgian brewer is to produce a wort that does not over attenuate. Over-attenuated beers, especially when weak, drink thin. The attenuation of a good running beer is
rarely, in Belgium, over 66 per cent.; or, in other words, a 15-lb. beer must not run down below 5 lbs. In districts where the beers are very weak, as at Liege, for example, where the beer weighs
1027 original gravity, an attenuation that does not go beyond 50 per cent, of that original gravity is found to be essential. The particular method of malting the barley, as well as its nature,
influences, of course, the attenuation."
This would give a beer of around 1.7% ABV! You couldn’t get pissed on that.
"The brewing processes carried out in Belgian breweries are very varied, although they mostly have the same end in view: the production of a full beer from a weak wort. The great bulk of English brewers mash upon lines that vary but a degree or two, and so, again, it is with German brewers. In Belgium, on the other hand, there are endless systems of brewing, differing very widely indeed from each other. I will confine myself to the description of a process that is carried out in many hundred breweries.
One of the essential features of all systems of brewing that aim at making a weak beer taste full, is that the preliminary mash must be conducted at a very low temperature. Many brewers mash cold,
as little water as possible being used. But a larger number mash with water at about 48° C. (118° F.), and in quantities sufficient to get an initial heat of about 42° C. (108° F.), at which temperature
the mash is generally loft to stand about half an hour, sometimes longer. At this temperature several things happen. The diastase is taken into solution and the starch granules swell up.
The soluble ferments which act on the nitrogenous matter of the grain find their maximum activity at or near this degree. Acidity is produced, sometimes very rapidly. Part of the increase in the acidity
is only apparent, and is due to the gradual dissolving out of the phosphates ; part, on the other hand, is duo to the direct intervention of acid ferments with which the husks of the malt are covered. This
acidity must, of course, react on the nitrogenous matters. So much for the theory of the matter: as a practical fact, you may take it for granted that letting the mash stand at about 42° C. (108° F.) considerably increases the body of the beer. But this
fulness is also dependant upon other factors."
This sounds like a protein rest to me, interesting he says it adds to the body of the beer.
"You will readily understand that a malt which has been soaking in the mash-tun for half an hour or more at 42° C. (108° F.) undergoes, when subsequently warmed up, either by the addition of hot water or by heating by a steam jacket, a very rapid and complete saccharification directly you arrive at temperatures at which the starch is gelatinised. If therefore mash which has been standing at 42° C. (108° F.) be just gradually heated up to 60° C. (140° F.) and then on to 75° C. (167° F.) you will generally produce a very thin beer. This undesirable result is easily accounted for; all the diastase that the malt contains has been brought into play, and the transformation of the starch into sugars has not taken place at the high temperature that you have finally reached (75° C. or 167° F.) but at somewhere about 60° C. (140° F.) ; the production of maltose is consequently excessive. This indeed constitutes the danger of digestive mashing, but Belgian brewers avoid this danger by a very simple method.
After the mash has stood at about 42° C. (108° F.) they let in an underlet of one or two barrels to the quarter of water at about 70° or 75° C. (158° or 167° F.), with which they nearly fill the tun, the rakes, of course, being kept running. The temperature of the goods runs up, perhaps, to 50° or 55° C. (122° or 131° F.), at which temperatures there is not, in practice, much starch gelatinised. They then open the mash-tun taps, the rakes still being kept revolving, and the wort, which is quite milky and sedimentary in appearance, the starch granules still being intact, is allowed to run off to the under-back and is pumped to the thick wort copper, the one fitted with a chain.
Some mash-tuns are fitted with what are known as extractors, which enable the thick wort to be got off more easily without running it all through the mash-tun plates. When pumped up into the chain
copper the thick wort, which of course contains the greater proportion of the diastase of the malt, is heated up to the boiling point, a short time being allowed at about 75° C. (167° F.) to admit of all
the starch that has been sufficiently modified on the malt floors to gelatinise at this temperature and be transformed.
While the thick wort is being heated in the chain copper more water, this time at near the boiling point, is run in under the mash tun plates, and the goods are brought up to 70° C. (158° F.). Owing
to the fact that a voluminous milky wort has already been pumped up to the chain copper, the amount of diastase remaining in the goods is restricted. Consequently the starch left in the tun does not undergo very rapid transformation, and saccharification takes place at about 70° C. (158° F.), the temperature to which the tun has been raised by the underlet of boiling water. The tun is then allowed to stand for about three-quarters of an hour, just enough to insure the worts running off bright, when the taps are set and this bright wort run off to the bright wort copper, the one without the chain. As soon as the bright wort has all run off the tun, the contents of the thick wort copper are let down on to the goods and mashed in.
The thick wort is sometimes brought back at the boiling temperature into the tun, and sometimes, when tho brewer has doubts about the diastatic capacity of his malt, the thick wort is first cooled down to about 80° C. (176° F.) before being run into the tun. It is scarcely necessary to say that this thick wort, after boiling, very generally contains large quantities of soluble starch. I have known cases where the grain had been so well modified on the malt floors as to insure the complete transformation of all the starch granules of the milky wort at 75° C. (167° F.), and consequently in these cases no further gelatinisation takes place at the boiling point. Such cases are however exceptional, and, generally speaking, the boiled thick wort comes back heavily charged with soluble starch into a mash-tun of goods which by this time are extremely poor in diastase. The mixture of the thick wort at 80° C. (176° F.), with the goods at 70° C. (158° F.), brings the tun up to about 75° C. (167° F.), at which temperature the products of hydrolysis are of coarse very dextrinous. That completes the mashing process proper."
So a protein rest but then deliberately inefficient starch breakdown to produce a poorly fermentable wort making a full bodied beer.
"As soon as the mash-tun has stood long enough to allow the thick wort to clarify, the taps are again set [i.e. opened] and the filtered wort is run off and pumped up into the bright wort copper to join the first wort already pumped up there. This first wort has generally been kept at about 75° C. (167° F.), so that if by any chance a little soluble starch should remain in the worts after clarification of the thick wort, such starch is transformed by the diastatic activity of the first wort. The remainder of the process consists of getting the extract out of the goods, and as the beers are weak there is abundance of sparging liquor to accomplish this, notwithstanding the fact that the return of the thick wort on to the goods has rather increased the gravity of the wort retained by them than diminished it. Or, in other words, the second wort pumped to the copper, coming as it does from the clarification of the thick wort, is generally, if not always, stronger than the first wort.
Now the ultimate result of this system of working may be summed up as follows :—The beer will have the body due to the presence of large quantities of dextrin [unfermentable carbohydrates]; it will have the body and the capacity for holding its head due to the modification which the nitrogenous matters [protein] have undergone while soaking at 42° C. (108° F.); it will also have the body due to boiling a portion of the husk of the grain, us it is evident that in the milky wort there is a good deal of husky matter. Indeed, most brewers now have a tap placed just above the false bottom, and draw off to the thick wort copper a good quantity of husk. It is also a curious fact that with these worts such a thing as yeast weakness- is unknown. Notwithstanding the fact that the attenuation of the wort does not generally exceed 66 per cent., about 15 kilos, of yeast are produced to the 100 of malt mashed, or, say, about 50 lbs. of liquid yeast to the quarter of 336 lbs. I have known as much as 19 or 20 kilos, of yeast produced to the 100 kilos, of malt mashed, or about 62 lbs. to the quarter. In England much less is produced. That this yeast is very strong is also a fact."
"Yeast weakness" was a problem that plagued brewers for many years, causing poor fermentation. It was eventually found adding small quantities of the mineral zinc would keep the yeast strong.
"Now the system of mashing that I have described contains many pitfalls. There is great danger, owing to the excessive destruction of diastase which goes on and the high temperatures of conversion, of getting soluble starch in the worts. Thus the unskilful brewer often produces gray and unstable beers. There is, however, absolutely no danger in the process, provided the operator has a clear conception of the principal laws which govern the transformation of starch.
So much for an all malt brew. If not trespassing too much on your time, I should like just to say a word or two as to the method of using raw grain in those breweries. The simple plant described just now is in my estimation all that is absolutely required for the perfect handling of raw cereals.
Rice or maize ground very fine is run into the chain copper into about 4 hectolitres of water for 100 kilos, of flour. From 5 to 10 per cent. of malt are added to prevent balling. I prefer the smaller
quantity, as if during the subsequent heating of the copper you have enough diastase to convert any appreciable quantities of starch, you have an unknown quantity of maltose formed, which will vary with the speed and method of heating and the quality of the malt. To exaggerate the point I want to illustrate, I have come across cases where as much as 20 per cent, of malt was added to the rice or maize flour, with the result that a great proportion of the starch was converted as well as gelatinised in the copper, and very thin beers were the result.
The fact is that if you want to produce full beers with raw grain, you must so arrange your brewing that it is on your raw grain that you depend for the great bulk of dextrin, while it is on your malt that you depend for the great bulk of maltose.
The raw grain is heated gradually, say from cold to boiling, in about 90 minutes, and is finally boiled for 20 minutes or half an hour. About an hour after the grain has been turned into the chain copper, the malt is mashed in the mash-tun at about 42° C. (108° F.) as before, and after standing for 30 minutes is then run up slowly to 70° C. (158° F.) by adding hot water. Every opportunity is therefor given the malt for producing the maximum amount of maltose that it will produce. Where it is considered advisable to boil a proportion of the husk of the malt, a portion of the malt-mash is pumped up to the raw grain copper, but care is taken only to pump up malt into this copper when the raw grain has reached about 180° or 185° F., and is consequently at a temperature at which the diastase of the malt will have no effect on it. After boiling, the raw grain is cooled down to 80° C. (176° F.) and the mixture of the raw grain at 80° C (17G° F.) and the malt at 70° C. (158° F.) brings the tun up gradually from 70° to 75° O. (158° to 167° F.). The starch of the raw grain is consequently, at these temperatures, mainly transformed into dextrin.
We again then obtain as before:—the body derived from the dextrin furnished by the raw grain, the body derived from the nitrogenous matters of the malt that has been soaked at 42° C. (108°F.), and the body derived from the proportion of husk that was boiled in the copper.
When flaked rice or maize is used the process is the same. Mash the malt alone at 42° C. (108° F.), stand half an hour, push up to 70° C. (158° F.) by an underlet of boiling water. When the tun is at 70° C. (158° F.) let one-third of the goods into the under-back and pump to the chain copper. Now add the flaked maize to the mash-tun where it undergoes saccharification at 70° C. (158° F.) (a very high temperature you notice). Boil the thick wort and bring it back on to the tun to get 75° C. (167° F.). Let the tun stand three-quarters of an hour and draw off the wort. This process is simplicity itself. According to the temperature at which you add your flaked maize and the quantity of it, you can vary the composition of your wort at will, and consequently the attenuation. The temperatures we use may seem high to you, but you must not forget that the reproduction of the yeast is insured by the preliminary low mashing. It is probable that such high saccharification temperatures employed without this preliminary soaking at about 108° F. would end in collapse of the yeast.
The proportion of raw grain that gives the best results upon the method that I have described is from 20 to 25 per cent. More may be used if the brewer is careful to use a little crystal malt to make
up the flavour. The beers are boiled from four to ten hours, according to the views of the brewer: long boiling increases the body of the beer.
The fermentation of beer in the carriage casks is, I believe, peculiar to Belgium, Franco and Holland. Many attempts have been made to introduce fermenting-tuns, but, with very few exceptions, the tuns
have been abandoned. The reason is to be sought in the fact that weak beers fermented in open tuns are liable to be very tasteless and very flat. Brewers avoid fermenting in tuns beers that weigh less
than 1040. Fermenting in a tun necessitates the racking of the beer into the carnage casks, and very weak beers will not stand racking, they seem to loose all their life and all their aroma.
Very many theories have been offered to account for the indifferent quality of weak beers fermented in tuns. I expect that the loss in quality which they undergo is due to a good many causes.
M. do Namur, of the Brewing School of Ghent, attributes the loss of flavour of beers fermented in an open tun to the escape of the ethers formed during the fermentation. Every one who has ever
smelt the gas coming off a fermenting-tun knows that there is some thing more than CO2 given off. De Namar says that the wood of the casks retains the ethers to a certain extent and then gives them off to the beer. As a. proof of what he brings forward, with regard to retention of ethers by the wood, he says that beers fermented or stored in a now cask are never quite so good as beers put into a cask that has been in previous use, the now wood absorbing all the ethers.
Moreover, ethers are volatile, and, according to de Namur, are liable to be driven off when racking the beer. CO2 is also lost, and the beers being weak, the secondary fermentation is not sufficient to again saturate them. The thorough saturation of a beer with CO2 is, of course, a very material point with regard to its flavour.
There’s no doubt about it, beer needs to have some condition in it.
"As a last explanation of the inferiority of weak beers fermented in tuns, it may be said that fermentation in casks being under no control often carries the heat up very high. I have often seen the thermometer register from 70° to 78° F. in these casks. Flavours are perhaps produced at these temperatures that are not produced in a tun where the temperature is kept down below 70° F. As soon as the pitched wort is run down into the casks an abundant white froth containing a good deal of yeast begins to work out at the bunghole and falls into the little tubs you see under the casks. This period of the fermentation corresponds I suppose to the sugarloaf or rocky white head of the fermentation in tuns."
Higher temperature fermentations do indeed lead to the production of more flavour active esters.
"When about a quarter of the contents of the casks has run over into tubs by reason of the abundant production of this white froth, the beer that has fallen into the tubs is poured back into the casks.
The white foam has, of course, resolved itself into liquid in the tubs. The pouring back of this beer thoroughly aerates and rouses the contents of the casks, and almost as soon as they are topped-up the yeast, this time thick and viscous, begins to work out at the bunghole and drops over into the tubs just as in the English cleansing process. Fermentation being completed, the general coarse pursued is as follows:—Finings prepared from fish skins are added to the beer and the remainder of the yeast and the bottoms are all thrown out with the finings by the bunghole, thus leaving the beer as good as racked bright in the cask with comparatively little loss of CO2 and of aroma. If the beers are running beers they are then immediately shived and sent out to the customers. They are never dry hopped. Dry hopping is unknown except for vatted beers."
Finings prepared from fish skins rather than swim bladders sound s bit odd, I wonder if he’d got things mixed up there.
"In some districts, as at Liege for instance, where the original gravity of the beer is only from 1025 to 1030, the fining process which I have described is applied earlier. This prevents the attenuation going
beyond 50 per cent. Moreover, a special yeast is used in that part of the country that gets sluggish as soon as the beer has dropped to ½ gravity, and submits to being ejected with finings. The beers are then immediately bunged as before, and the remaining yeast cells set up a violent so-called secondary fermentation, but which the pure yeast processes have abundantly proved is, at first at any rate, only a continuation of the incomplete primary fermentation. The pressure thus generated in these casks is very great, and the casks used in this part of the country have to be very thick and are now mostly pitched. These beers are of course tremendously "up," and unless brewed with excellent malt and a good deal of sugar are very apt to go thick. Successful brewers, however, send them out star bright and foaming. These cask processes are very interesting, but 1 should detain you much too long if I went into any more particulars with regard to them."
Mmmmm…very weak, very fizzy beers.
"The yeasts used in Belgium are peculiar in many respects, and differ very widely from English yeasts in their behaviour and in the flavour they communicate to the beer. Pure yeast, which Van Laer took so much pains to get generally used in Belgium, is still suffering from his original and very natural desire to follow Hansen's methods. Hansen's pure yeast of one species, however, got the brewers into
horrible messes; the yeast was sluggish and went to the bottom, and there was no secondary fermentation. Several species were tried but to no avail. It was then that Van Laer mixed the species. These mixtures or composite yeasts act perfectly, and are used in a. great many breweries. There are, however, unfortunately some brewers who tried the first pure yeast, Hansen's yeast, and whom the very name of pure yeast frightens. It will only be when their fright has subsided and they have learned from their confreres that the composite yeasts give good results, that they will try them and that the use of pure yeast will become general in Belgium."
The use of pure yeast took many decades more to take hold in Britain.
Having copied huge chunks I won't go into the discussion section apart from this titbit: apparently the strongest beer brewed in Belgium had a gravity of 1063, and it was made on the spontaneous fermentation system. I wonder what the Trappists were up to at the time?
