Saturday, 24 September 2011

Fermentation at George Younger in the 1880's

Time for another stroll through George Younger's Alloa brewery. This time to the fermenting department. What will we find?

But first let's make a slight detour to the cooling loft:

"Walking across the copper-house, we passed an immense tank measuring 40 feet by 15 feet, containing very cold water from one of the lesser wells, for cooling purposes, and then entered the refrigerator and cooling room, constructed a few feet below the level of the water tank referred to. This magnificent cooling loft measures 100 feet in length, and is divided in the centre by a louvred partition. The front portion overlooks the yard, and is covered by an open cooler, with central revolving fans, driven by steam power; the walls of the room are latticed all round. The back or brewhouse portion is the refrigerator room, and contains two of Morton's largest size horizontal refrigerators, capable of cooling together 130 barrels per hour. The walls and ceiling of the refrigerating room are lined with match-board, stained and varnished, and the room is lighted by numerous windows."
"Noted Breweries of Great Britain and Ireland, vol. 2", Alfred Barnard, 1889, pages 440 - 441.
This is a typical arrangement of the late 19th century. Go back to the early years of the 19th century and worts were cooled by open coolers alone. A system which worked well enough in the cooler months, but could be problematic in the summer when the ambient temperature was higher. The solution was the refirgerator. Where the wort was conducted through pipes over which cold water ran. The Morton refrigerator was the classic machine, used almost everywhere. You can see them nicely in the picture above. The big advantage of a refrigerator was that the ambient temperature was more or less irrelevant and worts could be cooled quickly no matter what the weather.

Another development was the addition of fans above the cooler to circulate air better and hence aid cooling. Like everything in a modern brewery, they were driven by belts and shafts from a steam engine.

Brewing science had come a long way since Pastuer's visit to Whitbread in the 1870's. They'd rushed out the next day and bought a microscope of their own. A couple of decades later and no self-respecting brewery would be without one:

"On one side of this apartment, fronted by a broad gallery, is the head brewer's room, which commands all the important proceedings in the brewery. It is a spacious office 40 feet square, having subsidiary lavatories and offices at the back, and being lighted by numerous windows. Around the walls are barley and hop-sampling counters, a testing sink, shelves filled with experimental jars and measuring apparatus, and a case of books. In the centre is Mr. Cooper's writing table, and, on one side, are desks for the use of his lieutenants, or under-brewers. At one corner there is a lofty grandfather's clock, of handsome appearance, more than a century old, which was purchased with the old brewery, and keeps splendid time. Here also is the microscope, without which no brewer's room is considered complete now-a-days, and also other scientific instruments considered absolute necessaries to the intelligent modern brewer."
"Noted Breweries of Great Britain and Ireland, vol. 2", Alfred Barnard, 1889, page 441.

Maybe Barnard had bladder trouble. That's my explanation for why he suddenly starts telling us where all the toilets are. He didn't do it in the first volume.

Finally were in the fermentation room, as promised:

"Leaving this interesting place behind us, we descended to the floor underneath, and proceeded to notice some of the rooms connected with the fermenting department, where the cooled wort from the refrigerators next makes its appearance. The No. 1 tun room, being the most important, first attracted our attention. It is both light and spacious, and measures 60 feet in length, with a 6-foot way intervening between the vessels. It contains fifteen fermenting tuns of various capacities, eleven of which are square, and four round. They all contain parachutes and attemperators, and possess a fermenting capacity of a thousand barrels. The object of the attemperators is to keep the temperature under thorough control, and to secure a necessary reduction of heat, before racking off the finished beers. On reaching the tuns, the cooled wort is inoculated — so to speak — with yeast, when fermentation immediately commences. The great consideration is to have sound and healthy yeast, a great desideratum with Messrs. Younger and Son, and to secure it they take infinite trouble, and exercise the greatest care.

Fermentation is certainly the most important process in the brewing, and the most difficult to conduct. Here again the thermometer plays an important part, and our guide informed us that he watches the operation with the closest attention, assisting the process when too languid, or controlling it when too violent. In this operation of the brewery, we are presented with some of the most pleasing and instructive phenomena of nature. The combinations that are formed during the process are interesting beyond comparison to the intelligent on looker. The elastic fluids and volatile principles that are extricated and escape from the liquor during fermentation, are now fully understood by the scientific brewer, and careful observation of these can alone secure continuity of character in the finished beers.

But we must keep to the practical, and enter into the matter of fact details connected with our two days' sojourn in this brewery. In the adjoining room, there are seven more squares of similar construction fermenting 500 barrels, and beyond, in course of construction, there is an extensive addition being made to this department, which will nearly double the fermenting capacity of the brewery. As will be seen from our sketch, the new building is two storeys high, and forms a continuation of the left wing of the brewery. It is being erected in the most approved style, and will contain fourteen square fermenting vessels, with a capacity of sixty-five barrels each, all fitted with the latest improvements, attemperators and parachutes. Beneath the Nos. 1 and 2 fermenting rooms, are two racking cellars and a store cellar, all paved with stone. The former contain the usual cleansing squares, racking pipes and fittings."
"Noted Breweries of Great Britain and Ireland, vol. 2", Alfred Barnard, 1889, pages 441 - 442.
Now that's interesting. They had both round and square fermenters. Most breweries went for one or the other. Alloa being known as the Burton of Scotland, and being similarly renowned for its Pale Ales, a comparison with Burton breweries is appropriate. Remember how small the fermenters were at Allsopp and Bass? No? Then I'll repeat it. Allsopp had 140 fifteen-barrel fermenters, and seventy 110-barrel ones. Bass had 117 squares of 45 barrels. Younger's 15 fermenters had a combined capacity of 1,000 barrels, an average of 66 barrels each. The ones in the second hall were slightly larger on average - 71 barrels.

Confused by the reference to parachutes? They're not to be confused with the paratrooper kind. These parachutes were more like inverted umbrellas, used for removing yeast from the top of wort. And naturally the fermenters were fitted with attemperators. In case you've forgotten, these were a network of pipes inside the fermenter through which cold water was circulated to reduce the temperature of the wort, if necessary. Worts were pitched at around 60º F and allowed to rise to the mid-70's. If the wort was getting too warm, the attemperator was switched on. They were also used at the end of fermentation to drop the temperature down to 60º F again to get the beer ready for racking. Whatever the weather, the temperature of the fermenting wort could be controlled precisely.

I've just realised we can make a nice comparison of fermentation capacity. I make Allsopp's 9,000 barrels and Bass's 5,265 barrels. George Younger's, after the expansion, would have been 2,410 barrels. Remember that Bass and Allsopp were the second and third largest breweries in Britain. It gives a good impression of the size of George Younger's operation.

But, care is needed when comparing Younger with the Burton brewers. Have you noticed what's missing from the inventory at Younger? Union sets. At Bass, the beer only stayed in the fermenters for a couple of days before being transferred to the unions. As all the fermentation was completed in the fermenters at Younger, the wort would have remained in them longer, at least four or five days.

I'm surprised at the lack of unions at George Younger. William Younger, the other big name in Scottish Pale Ale, did have them. I wonder why George Younger hadn't bothered with them?

That's me alsmost done with George Younger. Only the bottling stores left to take a peek inside. Won't that be fun?


Barm said...

I've now looked at the site of Younger's Candlerigg Brewery. It's not very big. Not when you think of it as being in the top ten breweries in the country, considering that Bass was being described as a city of beer. Perhaps they didn't have room for union sets?

Mac said...

The Candleriggs brewery was the third largest in Scotland behind William Younger and William McEwan (a relative of the Alloa Youngers) of Edinburgh.

The Pony Brand label shown is interesting - it was a non alcoholic (very low alcohol in fact) beer brewed at the time the Temperance Society was at it's strongest, just after World War One.

Youngers had bought the old Bass Crest Brewery in 1919, from Bass of Burton, who had bought out the ailing firm the previous year in order to finally resolve the trademark issue which had earlier caused litigations.