In the 1890's there was a lot of debate about the freedom given to brewers by the Free Mash Tun Act of 1880. And whether or not it should be withdrawn again. So much so that a parliamentary committee was set up to investigate the matter. The evidence given by various industry professionals is fascinating. And a rare opportunity to hear brewers of the period speak frankly about their trade.
The excerpt below is from the evidence given by Mr. R. Bannister, Fellow of the Institute of Chemistry and of the Chemical and Microscopical Societies who had worked for more than 33 years in the Inland Revenue Laboratory.
6596. Of course they find it advantageous? —Yes, it gets the beer into condition just before it is put into consumption.
6597. There is a certain amount of yeast left in the beer, which acts upon the sugar or saccharine matter? —Always, and then it goes into fermentation, and makes the beer lively and sparkling, and that is necessary in another way too, in a great number of instances; because when the beer is removed from the brewery there is a certain quantity of sediment in the cask, and the beer is not clear; and if the publican had to wait till the beer cleared itself, he would have to wait a considerable time; so that they generally make the beer clear with finings; and the use of finings always flattens the beer. It is therefore very necessary that there should be a little sugar present so as to allow the yeast to ferment it as soon as ever the finings have been added.
6598. It being an advantage to have recourse to priming, is there any reason why brewers should not resort to sugar or saccharine matters for priming, and be forced instead to go to a cold infusion of malt ?—A cold infusion of malt would not answer the purpose equally as well, because it is not bright.
6599. But whether the priming were done with sugar or whether the priming were done with malt extract, it would create difficulty in determining whether the beer had been brewed from malt only or from malt and substitutes ? —Yes ; but, of course, the greatest difficulty would arise from the use of the sugar.
6601. And of course if cold infusion of malt extract were used, that would also add in the same way to the sweetness of the beer?—Only to a very small degree.
6602. So far as it was effective for the purpose it would ? —Yes.
6603. As regards beer which has not been subject to priming, its sweetness has very little relation to the materials from which it was made, but to the degree of attenuation ? Entirely so.
6604. So that you might get a very sweet beer, if you wanted it, from all-malt; and you might get a beer which was not sweet at all from a mixture of malt and sugar?— That is so as a matter of course; it depends entirely upon the extent of the fermentation — and almost every brewer has his own plan of fermentation — and the degree to which he takes the fermentation in his finished beer.
6605. In the wort, after you add the yeast to it, which ferments most rapidly, the maltose or the glucose ? —The glucose goes first.
6606. Therefore what sugar would be left behind would be sugar derived from the malt, and not derived from the added glucose ? — There is a gradation ; the glucose goes more rapidly than the maltose, the maltose more rapidly than the malto-dextrine, and the maito-dextrine goes more rapidly than the dextrine."
There you have it. Primings were needed to restore the condition removed by fining. Basically helping beer to quickly drop bright and come into condition. Sounds fair enough to me.
I was going to end there. Until I read the next section. It's an interesting take on German beer purity:
6608. Do we understand that their beer is filtered and then charged artificially with carbonic acid ? — To a large extent.
6609. They add carbonic acid specially, instead of allowing the carbonic acid to develop in the beer ? — Yes, it can be consumed more quickly.
6610. And that is the reason why the German beer is commonly delivered under pressure? — Exactly; and the German beer must be quite bright, and therefore there must be practically no sediment in the beer, because if there is the slightest sediment the pressure would force that sediment to the top ; it would cause it, not to ferment, but it would agitate it, and the beer would not look bright in the glass ; so that you must have the German beer quite bright throughout.
6611. And I suppose the added carbonic acid might be equally regarded as an impurity ? — That is the inference.
6612. It is something added to the beer after it is made? —Yes.
6613. And that is really the reason, is it not, why German beer is sent out in such small casks, made so strong ? — That is so, and if the beer is to be tested, as I have seen it tested over and over again at exhibitions, they are particularly careful to charge it with carbonic acid before it goes to the jury.
6614. It is something in the same nature as soda water in a less degree ?—Yes.
6615. With the result, that if a cask has been opened in the morning, the beer gets very vapid before the evening ? — Yes, it does, and of course the addition of carbonic acid gas is for the purpose of overcoming the difficulty of not keeping it a sufficient length of time in the cellar, because if it were left for a longer time it would have more carbonic acid gas in it. They get it into consumption more quickly by the addition of the gas."
"Minutes of evidence taken before the Departmental committee on beer materials", 1899, page 247.
I've never seen CO2 called an impurity before. It seems Mr. Richardson was quite in tune with CAMRA and me.