Friday, 7 October 2011

Cleansing in Edinburgh and Alloa

Edinburgh and Alloa. Scotland's two great brewing centres. Comparisons are often made between their Ales and Pale Ales. But it seems brewing methods in the two towns weren't identical.

How do I know that? Easy. I learned it from this passage:

"With the Edinburgh brewers, little or no fermentation takes place, and ale is never racked into other casks; but in Alloa, Stirling, and Perth, which are the best districts for brewing ale next to Edinburgh, they run the finished ale into butts, and afterward rack into barrels, as orders are executed. Those two methods of cleansing the gyle, in the Scotch system of brewing, are particularly worthy of the notice of the reader: both methods are the best suitable to the respective localities. The Edinburgh brewers pursue their method because their ale is sent out at once to the customers' cellars. The Alloa district brew large quantities which are sent to Glasgow, and other parts, generally for immediate use. In racking, the Alloa brewers prepare what they term fillings, which are worts of the same brewing, set at the quick fermentation heat, 60° or 62°, and use part of this store in racking, putting an English pint into each barrel. The Edinburgh brewers rely on the fine condition of their ale, and add nothing whatever before sending out the stock. It has been necessary to be particular, that brewers may understand precisely the two methods of finishing the gyle by the Scotch system.

Sometimes brewers overturn it into a clean tun or square, to check too rapid fermentation and cool the whole brewing, or to prepare for keeping a length of time; but for immediate consumption, the two methods above described are adopted."
"The complete practical brewer" by Marcus Lafayette Byrn, 1860, pages 75 - 76.

This confirms one of the points made by Muspratt in yesterday's text: Edinburgh brewers didn't cleanse in separate vessels like most English brewers. Brewers from other Scottish towns, however, operated differently, putting beer into butts between fermentation and racking.

Those "fillings" are worth noting. They are described elsewhere in the book as half-fermented wort. The practice is a type of kräuseing, similar to the way Guinness added unfermented gyle as primings.

It sounds as if the brewers Alloa were sending out running Ales, i.e. beers to consumed immediately while Edinburgh brewers shipped beers meant to be cellared. I know there was a tradition of not fining beer in Scotland. The father of one of my brother's classmates ran a pub that sold S & N beer. He had trouble with the clarity of one barrel and the brewery suggested that he tried adding finings. They sent the beer out unfined.

There's that throwaway remark about Alloa breweries sending lots of beer to Glasgow. Not other Scottish towns, but specifically Glasgow. Could this be another cause of the lack of brewing in Glasgow?

After a slow start, my research has left heaped files of material all around me. I'm not sure how long it will take me to get through. I may have to make autumn Scottish season.


Gary Gillman said...

There is a very similar discussion in Thomson & Stewart's text of 1849. They were Scots, one a brewer, the other a chemistry teacher in Glasgow.

As I read that discussion, the Edinburgh practice was indeed not to cleanse into small casks or pontoes. In England, if you didn't transfer the gyle from the fermenter to cleansing casks, e.g. Unions in Burton, the temperature in the vats would risk running too high with the chance of a spoiled batch from acetification. Also, the longer the beer was left in vat, the greater the chance of it being yeast-bitten.

Transfer to smaller vessels would slow (not stop completely) fermentation, thus minimizing the chance of a bad ferment. I am not sure how this would prevent yeast-biting though. Perhaps because the total time the beer was in contact with yeast before racking was less than in Scotland.

In Scotland, since the climate was colder, you could keep the beer longer in the fermenting vat until the fermentation stopped of its own accord and the beer "cleansed itself" as they put it. You would simply skim the yeast and/or pour the beer off the lees, and rack it into trade casks. The beer wouldn't ferment any further in the casks (they said). Hence, part of Scots practice was always to brewery-condition, not cask-condition. This form of the beer would be similar to most current North American craft beer.

Why would yeast-biting not be a problem in Edinburgh? I'm not sure, perhaps the colder temperatures assisted the yeast to precipitate very fully. Thomson & Stewart speak of Edinburgh brewers removing yeast both from the top and bottom of the vat before racking into trade casks: they seem to have had no trouble doing this in a way to ensure the beer wouldn't further ferment after racking. For it not to ferment, you'd have to get most of the yeast out in the one stage of fermenting, and they did.

And so the idea of not needing finings makes sense because clearly you wouldn't need to it for a brewery-conditioned product. For a krausened one, it might be different, but I gather the floc was able typically to fall down on its own - again I believe typically cold temperatures would have assisted this.

Thomson & Stewart state that in contrast, Alloa's beer required fillings to ensure proper condition for its market, so this does tie into the idea of the beer typically being consumed far away. Indeed, they said the beer sometimes was too "hard" due to this, meaning I think it was too attenuated, not necessarily sour. They pointed out the reverse case that sometimes Edinburgh beer was too "soft", but then since Edinburgh customers did not like a pronounced bitter taste, this was not really a defect (they said).

The beer treated with fillings is certainly a form of cask ale, so the two traditions clearly co-existed in Scotland.

If you did it the Edinburgh way but sent the beer far away, you probably would have risked in 1850, i) the beer becoming flat in those days before force-carbonation, and ii) the beer becoming oxidized (damp paper oxidation). Beer on its lees otherwise will-brewed will not oxidize as quickly. Hence, "beer needs grounds".


marquis said...

Gary, the climate in Edinburgh is almost identical to that of Burton.They are after all only a couple of hundred miles apart and at roughly the same altitude.

Gary Gillman said...

I don't doubt this, however in my readings, many early brewing commentators discuss early Scots practices of pitching and fermenting at generally lower temperatures in relation to English brewing. Too many such that it can't have been something real, IMO. Burton is one place in England, and it is entirely possible that in the artisan phase of brewing, its practices were similar to Scotland's. Indeed, there are parallels such as that Scotch ale and Burton ale could reach similar strengths, and also that beer in both places seemed often to clarify quickly without resort to finings. (This latter factor may have had something to do with climate, in part at least).

But it's one area, Burton/Trent Valley, southern English brewing would have been carried on in a warmer climate and the writers mentioned probably had it in mind.


Ron Pattinson said...

Gary, the pitching temperature has nothing to do with the climate. Not after the introduction of attemperators in the late 18th century.

Yes, everyone keeps saying they fermented much cooler, but the brewing records don't confirm that. A little cooler, yes, but only a few degrees.

Gary Gillman said...

Ron, my view on all this is that things simply changed - evolved - by the time of the records you mentioned. And when people write in the public record, due to publication lag as it's often called, they are often recounting the practices of an earlier period. I am not obviously contradicting what you found in 1800's records.

And then too, did all Scottish breweries from 1750 on, say, have this equipment? Did it always work?

Finally, terroir as it's called plays an important part in the products of any area and I think it did with Scots brewing well into the 1800's and even until now.

It's my deduction from all that I have read and indeed tasted, e.g., Scots ales have always seemed to me far less estery than English ales. I believe termperature originally contributed to this, and either it still may, or the beers are maintained to have a traditional character because of, well, tradition. It's an interpretation I have of the full history including what you have found.