Cold and Sparkling Ales

MEETING HELD on Tuesday, November 9^th, 1897, at the Offices of Messrs. IND COOPE & CO., BURTON-ON-TRENT.

Mr. C. Howard Tripp (President) in the Chair.
The following paper was read and discussed: —

Cold and Sparkling Ales.
By H. Van Laer, D.Sc. (Director of the Brewing School, Ghent, Belgium).

Had I been able to read my paper last May, as I originally intended, 1 should have chosen for its subject a method of fermentation which interested me very much during my visit to the United States of America. I refer to the Pfaudler vacuum system of fermentation.

But as I at that time treated the subject in Belgium, and as, on the other hand, Dr. Wyatt has recently published a paper on this matter, in the American Brewers’ Journal, which is the more interesting in that it is inspired by the results of personal experience, a description of this system by myself would present but little interest.

Up to the present the vacuum system has not been applied to top fermentation beers, because in America these beers are gradually disappearing in favour of those produced by bottom fermentation, which, in fact, form the chief American brewing industry. It may, however, be conceived that in view of the facility of collecting top fermentation yeast, this system may become applicable to the beers’ produced by it.

In any case, even if experience shows that it is necessary to renounce the idea of carrying out the fermentation of ale, stout, and Belgian beers with assistance of the excessive aeration which is necessary for vacuum bottom beers, the vacuum fermentation casks will recommend themselves on account of the fact that they allow of the economic collection of the carbonic anhydride from the primary fermentation and its utilisation for subsequent carbonating. It must be acknowledged that our present methods of conditioning beers by making use of the carbonic anhydride produced during fermentation are still both primitive and irrational. Large quantities of this gas are lost during the primary fermentation, of which there is so much need after the secondary fermentation.

There are some breweries in which by a very simple arrangement (now forming a part of the vacuum system) the carbonic acid gas which is collected by the pump during the fermentation may be stored in suitable vessels under pressure, instead of being allowed to ran to waste. In these the gas is used either for wholly carbonating the cold filtered beers at the end of the nine days’ fermentation, or for partially carbonating them, by introducing a small quantity of the gas with the finished krausened beer ns it leaves the cooler, and before it passes into the filter on its way to the racking bench.

It will, I think, be interesting in this short paper to complete Dr. Wyatt’s work, by entering into the details of carbonating beers. 1 will first take up my position from the point of view of lager beer; it will then be easier for us to look at the question in connection with that produced by top fermentation.

Methods of carbonating are not wanting in the United States. It would be tedious to describe them all now. I will therefore limit myself to speaking of the system connected with the vacuum fermentation, as I have seen it at work at the Phoenix Brewery, Pittsburgh, a brewery whose products I have found of the very highest quality.

The beer after leaving the vacuum casks is cooled to 35° F., which may be effected in special vessels provided with air coil, in which an un-congealable mixture circulates. There is, however, no objection to this refrigerating being done in the vacuum tank itself during the settling period. The beer is then filtered, the filter being preferably arranged so that the liquid may run through it by gravity.  

The filter must be carefully laid in so that it does not leak. When starting it must be filled slowly, and no air should be left in it before running.

The bright beer finally passes into a special vessel (beer cask), hermetically closed, from which it is passed out to the carbonator. This is of a capacity sufficient to deal with 34 barrels per hour. It is composed of two distinct parts: —(a) Of a saturator, to which the beer is conveyed through a tube from the beer cask; it goes out, charged with gas, by the opposite tube, which leads to the beer pump. The carbonic acid is injected at a pressure of 30 to 40 lbs. per square inch in the middle of the running liquid, (b) Of a pressure reducer consisting of two batteries of four powerful metallic tubes. The diameter of these tubes increases from the first to the fourth. The batteries are independent of each other.

The mixture of beer and gas which comes out of the saturator is taken by a pump which compresses it and drives it back to the carbonator at a pressure of 125 to 200 lbs. per square inch. As a rule, the best pressure to maintain on the carbonator inlet is 160 lbs., and the pressure of the gas 50 lbs., but this depends almost entirely on the capacity and speed of the pumps, and it is best to take a sample of the beer every 5 or 10 minutes, to determine if it contains sufficient gas, until the correct pressure and speed are arrived at.

This beer, saturated with carbonic anhydride, passes through the tubes of the carbonator. Following its passage through the spaces which become larger and larger, the pressure is reduced to 15 or 20 lbs. at its exit. It is thence run into a storage cask for carbonated beer, in which the liquid is prevented from frothing by maintaining a counter-pressure of air little inferior in strength to the tension it possesses when issuing from the carbonator.

The vessel containing the beer to be carbonated should be at ft certain height from the ground; the liquid can thus be submitted to an air-pressure sufficient to ensure the beer attaining saturation with a pressure of 5 to 10 lbs. Thanks to the motion of the pump, the gas follows the current of the beer, and cannot re-enter the beer cask. After two or three months’ experience with this apparatus, the motion of the faucets and the regulating of the respective pressures are carried out with ease. Thus, if the beer is not frothing enough, the pressure of gas when it enters the saturator is slightly increased. If, when it enters the carbonator, the pressure is not sufficient, the valve is closed a little, which controls the inlet of the first tubes of the carbonator.

If the beer froths in the storage casks for carbonated beer, a little higher pressure is applied without, however, going beyond that necessary for racking.

When the beer to be treated has passed through the saturator, which can be easily seen by the indicator attached to it, the admission of the gas is discontinued, the communication with the receiver out off, and the pump stopped. It only remains to circulate a current of water in the carbonator in order to cleanse it, and every week to treat it with a hot solution of caustic soda.

To recapitulate, it is seen that the carbonating of lager beer comprises the following operations: (a) Cooling to 34° F.
(b) Filtering.
(c) Introduction into a reservoir which supplies the carbonator.
(d) Carbonating.
(e) Introduction into a reservoir which supplies the casks.
(f) Hacking into casks under a counter-pressure of air.

If we consider now the top fermentation beers, we see that a great number of American brewers have applied themselves to the production of what is called “cold and sparkling ale,” Meanwhile, certain brewers assert that the system robs the beer of its ale taste; others (and these constitute the majority) have received the process with favour. I have tasted carbonated ales in several breweries in New York State which left nothing to be desired either in taste or brilliancy. On the other hand, in a Pennsylvania brewery, I came across a beer artificially charged with carbonic acid gas which, both as to taste and brilliancy, appeared to me inferior to the same beer not so treated. I should add that in this case the beer was first cooled, carbonated, and then filtered, whereas the process, which appears to have the greatest success, consists: —

(1) In bringing the temperature of the ale back to 32° F. immediately after fermentation; if the beer is bright, it then becomes very cloudy, and acquires a bitter and very disagreeable taste.

(2) In filtering in order to remove the yeasts, albuminoid sub stances, resins, &c., which might eventually make the beer thick after it had been put on the market.

(3) In charging the brilliant filtered beer with carbonic acid gas at a pressure sufficient to ensure a minimum of 0.390 per cent. of carbonic anhydride.

(4) In racking the ales thus carbonated into casks under a counter-pressure of air or carbonic acid slightly less than that to which they were submitted at their exit from the carbonator.

This last operation is carried out with success in many establishments by means of the “Golden Gate” valves and racking apparatus which I will presently describe. In certain manufactories the beer, after it has been cooled to 32° F, is turned into the chips casks, in which is then added about 8 lbs. of hops for every 62 barrels of beer, together with a little isinglass. The beer is here left for 10 or 12 days in a room with a temperature of 29—34° F., after which it is filtered and carbonated.

Racking valves enable the racking to be conducted without any loss of the carbonic acid gas. Instead of being filled through the bung hole, the casks are filled by means of two valves which each barrel possesses. These are constructed in such fashion that once the interior of the cask is pat in communication with the exterior, it is impossible to interrupt this communication without closing the cask.

The carbonating process for sale in cask, as it is applied in America, may appear complicated. The greatest difficulty of its application to the ordinary English and Belgian beers consists in the refrigerating which the liquid undergoes before filtration. Notwithstanding improvements in ice machines and the existence of cheap, small machines for moderate breweries, many practical men seem still to be averse to it. The practice of charging beers with commercial carbonic acid will, however, certainly be in vogue in England, France, arid Belgium in a few years. It will, perhaps, precede that of collecting the carbonic acid disengaged during the primary fermentation, because it will require less profound modification in the present plant of top fermentation breweries. The future is certainly against the present crude methods of conditioning beers. Whoever has visited the brewery of Pabst, at Milwaukee, cannot fail to have been impressed by the enthusiasm with which the proprietor and his collaborators speak of the success of the carbonation of their products from point of view of taste, economy, and keeping properties.

I have tried to apply the American process of saturating ales to Belgian top fermentation beers, and I am able to say that the results are entirely satisfactory. Practical experiments with English, ales permit me also to affirm that if the carbonating process is properly carried out, it gives brilliant beers having an extremely pure taste; when bottled, no deposit appears until many days after the time in which this would appear in the case of the same beers not carbonated.

In conclusion, I am of opinion that the satisfactory results obtained up to now in this path, at least, deserve investigation at the hands of practical men.

Discussion.
Mr. P. E. Lott, who had listened with great interest to the remarks of Dr. Van Laer, felt that the author had opened up a new subject when he suggested the application of the process practised in America to English beers. Carbonating was at present resorted to in the case of certain bottled beers. In his opinion, however, it would take many years to introduce a process involving so many novel and distinct operations, such as cooling, filtering, and carbonating, which must produce, moreover, a vast alteration in the national beverage of this country. He thought also it would take longer than the author anticipated to get Englishmen to appreciate the altered conditions, seeing that English brewers produced beers by their present method, such as were not exceeded in quality by those made by any other process, unless it could be shown that the new process produced a better article. He wished to know the principle of the filtration method adopted for continental beers.

Mr. W. W. Butler said he would like to know whether beers fermented under the vacuum system lost in alcohol by being submitted to the reduced pressure, and if any attempt were made to remedy the loss. He also desired to learn whether isinglass was mixed with the beer, and put into the chip cask before filtration. He did not quite see what advantage was gained by raising the pressure and then lowering it again during the carbonation process. Was the counter-pressure in the beer cask produced by carbonic acid gas or air? With regard io racking under counter-pressure, the author had not stated if an attempt was made to remove the air in the cask; he understood that it was driven back into the gas reservoir, and it therefore appeared to him that they would get a mixture of air and carbonic acid gas. His experience was that if air were passed into flat beer, it destroyed the flavour and gave it a soapy taste. Besides carbonic acid gas, other gases, such as sulphuretted hydrogen, were, of course, produced during fermentation. Was the gas used for carbonation purified in any way?

Mr. C. C. Puffer (an American visitor) said that the reputation of Burton ales in America was very high. Dr. Van Laer had, however, been talking about another kind of ale, a kind that was drawn brilliant and cold. They wore fond of cold drinks in America, and they drank their ale from the ice. They liked to see their ale brilliant, and the only way of attaining that was the method which Dr. Van Laer had described. The gas injected was precisely that required, and the ales became similar to what they would be if they were bunged up and the fermentation gases kept in. The beer was filtered cold and bright; it was carbonated, and racked under pressure into large casks; it then went down into the saloon just as cool as lager beer. It got a little warmer after being drawn, the escaping gas giving a sparkling ale, and one of the reasons for patting on the additional pressure was that it gave the beer a creamy appearance which was appreciated.

Mr. J. G. Wells asked whether the system had been applied to top fermentation, and if so, how the difficulty of removing the yeast was surmounted, as English beers were much more heavily hopped than lager and other beers, and the hop haze which was produced on cooling down to a low temperature was difficult to get rid of. He would like to know whether the filtration process was efficacious in removing it.

Dr. Van Laer, in reply, thought that the best general filters were those in which cellulose or paper pulp was used as a filtering medium. The medium was simply washed with hot water each time it was used. He agreed with Mr. Lott that English beers were at present very good, but he did not see why they should not be farther improved. The beer was first put into the chip cask with a small quantity of hops and isinglass; it was subsequently filtered. With regard to the loss of alcohol daring fermentation he thought that Dr. Wyatt, of New York, had shown that the loss was only very little. The pressure must be raised and then lowered again daring the carbonation process, in order to obtain a lasting foam. The counter pressure in the beer cask was produced by air. The gas removed by the vacuum was not lost. Tho carbonic acid gas produced in the primary fermentation could be used for the carbonating process. The vacuum process was only used in America for lager beer and not for top fermentation beer.

The President, in remarking upon the practical interest of the subject of the paper, said that since Dr. Van Laer’s visit to America last year he much admired the American process, and he looked upon America as one of the countries in which brewing had made great advances. But in England there were many prejudices, if he might call them so, to be overcome. With regard to bottled beers their forefathers had been accustomed to long storage, and he believed it would be a long time before they would succeed in overcoming the prejudices of these bottled beer drinkers. He therefore saw a great difficulty in the general adoption of the carbonating process. Then, again, the working classes were accustomed to beers that were well hopped and sparkling, having become conditioned in the cask. The adoption of special plant would take so much time and money that he feared the change could not be effected with much practical benefit. It was asking the brewers of this country to undertake a great change in their plant and mode of business, and to cast aside what had been going on with groat success for many centuries. Before they could adopt such a radical change, they would want to know the cost and what real beneficial results would accrue. At the same time their thanks were due to Dr. Van Laer for his most interesting and valuable paper, and he had much pleasure in proposing a hearty vote of thanks to him.

Dr. Van Laer having appropriately acknowledged the vote of thanks, the proceedings terminated.