Aitken's Old Brewery (part two)

We're back in the old-ish Aitken's brewery. Though as you read the passage below you'll realise that it had already been greatly altered and enlarged.

The original brewery was all on the south side of Newmarket street. But during the 19th century a new, much larger set of buildings had been added on the north side. These wren't concerned with brewing, boiling or fermenting, but were ancillary buildings such as stores.

"Retracing our steps, we came to the mashing-stage, 40 feet square, situated in the centre of the brewhouse. Here we were shown two mashtuns, constructed entirely of copper, and commanded by a Steel's mashing machine. They both contain gun-metal draining-plates, and each is capable of mashing twenty quarters of malt. The underbacks are below the tuns, from which the wort is pumped up direct to the coppers. We have previously written so much on the nature and object of the mashing vessels used in the breweries, that, on the present occasion, our attention will be more particularly directed to the next and following processes."
"The Noted Breweries of Great Britain and Ireland, vol. 2" by Alfred Barnard, 1889, page 194.

That's what I've been waiting for: the capacity of the mash tuns. At 4 barrels a quarter, that's 80 barrels a brew per mashtun. Assuming one brew in each per day and 300 brew days a year, that comes to 48,000 barrels annually. Not enormous by English standards, but a reasonably-sized regional brewer in Scotland. Thanks for not bothering to describe them in any more detail, Alfred. At least there's an illustration.

Looking at the way that bloke is standing in the mash tun, it doesn’t look like it has internal rakes. Which tells me something. What? That they almost certainly didn’t perform underlet mashing like London brewers. About an hour into the mash more hot water is added to the mash from below (via the underlet, hence the name) to increase the temperature of the bed. It’s a simple form of step mashing. Whitbread were still mashing this way at Chiswell Street in the 1970’s.

Underlet mashing is one of the reasons many London brewers retained internal rakes even after installing a Steel’s masher. Because the practice was to have the rakes revolve once or twice after the underlet to mix the hot water added thoroughly with the grain.

"After this we made our way to the cooling department, covering the top storeys of the adjoining building, and overlooking the main thoroughfare. One of the most striking objects it contains is the hop-back, a large vessel with a graduated bottom, constructed entirely of copper, and containing across its breadth, at the far end, two rows of copper draining-plates. This vessel is used as a combined hop-back and open cooler, and is unlike any we have seen before.

In the same apartment there are two Morton's refrigerators, cooling at the rate of thirty barrels per hour each, where the ale wort is further cooled over the mazy lines of innumerable cold-water pipes before passing into the  great copper mains, which convey it to the fermenting rooms."
"The Noted Breweries of Great Britain and Ireland, vol. 2" by Alfred Barnard, 1889, page 194.

I wouldn't have minded an illustration of that cooler/hop back device. I can't quite get an image of it in my head. We all know what a Morton's refrigerator is, don't we? No? OK then. It's a bed of horizontal copper pipes through which chilled water flows. Wort flows over the pipes and is cooled.

"Our progress was now downwards, and after inspecting the furnace fires, or copper hearths, as they are called, we made our way back to the courtyard.

Passing beneath the archway, immediately within, on the left-hand side, appears the magnificent tun-room, re-built in the year 1866 and again considerably altered and enlarged in 1878. The building is of solid construction, and is lighted by nine windows in the roof, which contains improved patent ventilators, is ceiled with pitch-pine, and is supported by immense iron columns All the vessels are elevated on brick piers, and fronted by a gallery, which adds much to the impressive effect. The illustration, which heads this chapter, is taken from a photograph, and shows a section of the interior of this tun-room. There are fifteen vessels in this department, all constructed of polished pine, nine of them are fermenting squares, and the other six settling backs, and each is fitted with an attemperator. The copper mains, by which they are filled, are in short lengths and detachable, so as to be easily cleaned. At one corner of the room there is a small Otto gas engine, used for pumping the beer from the tuns into the backs. From this side of the brewery the beer is conveyed through great copper mains, laid under the street, to the racking-rooms on the north side of the brewery. Before leaving this place, we paid a visit to the engine-room, situated under the mashing-stage, and containing an engine of fifteen horse-power, and a large steam boiler. Here also are two sets of pumps for the coolers and refrigerators, reversible, in case of breakdown, and the two great metal underbacks, each fitted with duplicate stopcocks. Walking through this apartment we came to a paved chamber where the spent hops are pressed. The machine is worked by hydraulic pressure, and the wort expressed from the hops is pumped up again to the refrigerators, from which it passes to the fermenting vessels.
"The Noted Breweries of Great Britain and Ireland, vol. 2" by Alfred Barnard, 1889, pages 194-195.

It's clear that Aitken's brewery had been increasing its size and updating its equipment frequently in the second half of the 19th century. Boom days for Scottish brewing.

I'm not 100% sure what is meant by "nine of them are fermenting squares, and the other six settling backs". Fermenting squares I understand. You can see them in the illustration. Settling backs sound to me like part of a dropping system. It's a shame there's not more description of how these two types of vessel were used.

Fullers had fermenting rounds from which fermenting wort was dropped into settling squares. The way Fullers system of fermentation worked, the beer was only in the rounds 24 hours and several days in the squares. I can't see that working with the setup at Aitken, where there were fewer settling backs than fermenting squares. My guess would (and this is only a guess) that the beer was transferred to the settling backs when fermentation was pretty well complete. That would tally with the description of beer sometimes being put into squares in Edinburgh breweries, mostly to cool it down.

Those fermenting squares look pretty large to me. Look at the height of the things. I reckon they must be 12 feet square and the wort at least six feet deep. A quick calculation (an imperial gallon is 277.42 cubic inches) gives me a figure of about 150 barrels. That's much bigger than the piddling 40 or 50 barrel ones they had at William Younger. Which might explain why they need the settling backs. A larger volume of fermenting wort generates more heat.

Pressing spent hops to squeeze out the last drops of wort was becoming commonplace in large industrial breweries. I'm sure it still goes on today. But what about the quality of the wort extracted? Wouldn't it tend to be full of crap from the hops?

There will be at least more more instalment on the old Aitken brewery. Then we can move on to the recollections of former Aitken employees.

The Shore Brewery, Alloa (part three)

Yet more on Calder. When we finally get a glimpse of the shiny things.

I've no time for a long introduction. I'll let Barnard do the talking.

"Our steps were first directed to the ground floor of the malting which adjoins the brewhouse, where is situated the mill for crushing the malt, and from whence it is conveyed to the grist-house. Next, we ascended some stone steps, which lead into the brewhouse, a square structure built with stone, and having an open louvred roof. Making our way to the top gallery, we were shown a domed heating copper, holding fifty barrels, constructed of copper, and fitted with a manhole. It is commanded by the cold-liquor tank, and is for heating the brewing water, which runs thence through a copper main direct into one of Steel's mashing machines.

Returning to the floor, we took a peep at the mash-tun standing in the centre of the house, which is constructed of oak and fitted with gun-metal draining plates. It is a seventeen-quarter tun, and is generally used twice a day, to meet the increased demand for Calder's ale. Beneath the tun there is an underback, from whence the wort is pumped up to the copper, whither we followed it. Ascending another stair, to a gallery placed at a great elevation, we found ourselves on a level with the copper, a fine vessel 10 feet in diameter, which is constructed of copper, is heated by fire, and holds eighty barrels. In a recess on this stage, or gallery, is the brewer's sampling sink, and close to it, the grist hopper, etc. ."
"Noted Breweries of Great Britain and Ireland, vol. 4", Alfred Barnard, 1890, page 390.

Scottish breweries were sturdily built. Often, like the Shore Brewery, of stone. It may not have been as grand as Willaim Younger's breweries in Edinburgh (they looked like castles), but it was still built like a brick shithouse.

Steel's masher. If it seems like everyone had one, that's because they did. It's an incredibly useful piece of equipment, allowing a brewer to fine-tune the consistency of his mash. It's no wonder that they're still common.

Now it's time for my favourite bit: mashtun mathematics. Calder had a single 17-quarter mashtun, used twice a day. Reckoning about 4 barrels to the quarter, that's a daily capacity of around 136 barrels. Or around 40,000 barrels a year. Which is very similar to the 50,000 barrel capacity quoted in their 1905 prospectus. Not a huge brewery by any means.

Let's move on to the cooling and fermenting and cooling departments.

"Passing into the next building, we ascended a flight of steps, leading up from the cleansing room to the cooling department. It occupies the topmost storey of the fermenting-house, which measures 60 feet square, and looks out on to the quay and river. The walls are louvred on all sides from floor to roof, hence the breezes from the Forth play pretty freely throughout the building, and the wort is rapidly cooled. On the west side of this chamber stands the hop-back, constructed of pine, and fitted with gun-metal draining plates. It is divided off at one end, where there is a surface aerator, through which the wort is conducted to two large coolers ; these occupy a considerable portion of the floor; and they are connected with two of Morton's horizontal refrigerators, which have a capacity of forty barrels per hour, and are cooled by well water. From these machines, the worts descend to the tun-rooms below, the larger of which contains four square fermenting vats, with a capacity of 300 barrels, where also are the tanks for holding the store yeast. In the smaller room, are five fermenting rounds, with a capacity of 180 barrels, and both rooms are fitted throughout with hot and cold water pipes.

Following our guide down a narrow stair, we reached the settling-square room, a chamber measuring 50 feet in length, and having numerous small windows looking out on the yard and road. It contains, besides other vessels, six settling-squares, constructed of pinewood, and fitted with attemperators. Descending still lower, we came to the basement of the building, where the cleansing operations are completed, and the beer finished for delivery to customers. Through a wide doorway, we passed into the cellars, where certain classes of ale are matured and stored for the local trade. The most important, however, is the cellar, situated in the building on the quay. This fine structure, which was erected some years ago by Mr. Calder, the senior partner, is of great height and capacity. The walls are 2.5 feet thick, and space has been left within the building for putting up another storey. This immense cellar is used principally for pale ales, and 6,000 barrels can be stored therein. Adjoining this cellar, is an export bottling store of similar dimensions, containing two storeys. At the back of the ground floor, the bottle-washing is conducted, the front portion being used for the filling operations. The upper floor is used for labelling, capsuling, and packing the bottled beers, for shipping to Australia and the West Indies. Included within this block, is the brewer's private house, several other stores, some houses for the workmen, a stable yard and a dray shed."
"Noted Breweries of Great Britain and Ireland, vol. 4", Alfred Barnard, 1890, pages 390 - 391.

You can imagine how drafty that cooling loft must have been. The brewery had an pretty exposed position, virtually on the shore of the Forth. The same comment as I made about Steel's mashers applies to Morton's refrigerators. Everyone used them. Though unlike the mashers, refrigerators of this type have been superseded by my modern devices. There's another reason why wells were important: as a supply of cold water. Deep wells are totally immune to the vagaries of the surface temperature.

Time for another bit of brewhouse calculus. Four squares of 300 barrels. Is that each or combined? I suspect combined. The brew-length was only 70-odd barrels. It would take two days of brews (brewing twice a day) to fill a 300-barrel square. Whereas 75-barrel fermenters would contain a single brew each. 480 barrels fermentation capacity doesn't seem like much. Or enough to keep pace with the mash tun. Depending on how long fermentation took. But look, they're using settling squares. The wort probably didn't stay in the fermenters more than two or three days before being dropped into the settling square. Using each of the fermenters twice a week would give enough capacity to match the mash tun virtually exactly. 960 divided by 12 (two brews each day, six days a week) is 80. Or a little more than the brew-length of seventy-something barrels.

This is where I get confused. The cleansing department ins below the settling squares. Surely the settling squares were for cleansing? Or did they, as described in an earlier post, run the beer into butts for cleansing? Is that what was in the basement?

In the 1890's not everything was running beer yet. Explaining wht some types of beer still needed to be matured in the brewery cellar. Almost certainly this would have included some of their Pale Ales. This was still brewed sometimes as a Stock beer.

That cellar on the quayside sounds totally out of proportion. 6,000 barrels is about two months worth of production. To have that capacity just for Pale Ale says much about Calder's trade. And how long Pale Ale was being stored before sale. As the 19th century progressed, beers was increasingly exported in bottles. Which meant brewers needed a whole set of new equipment to wash and fill the bottles. Funny the two destinations that are mentioned: Australia and the West Indies. We saw just a couple of days ago that many Scottish brewers were exporting to Australia in 1910.

The most exciting bit is still to come. When we sample Calder's beers.

The dropping system of fermentation

I'm such a populist. I should try choosing more obscure topics. Or you'll start calling me the Daily Star of beer blogs.

I was much intrigued by the dropping round and settling square kept as a museum piece in the Fuller's brewery. For one thing, it gave me chance to see exactly what an attemperator looked like. And the brewer, John Keeling, explained to me how it worked. He told me that the wort was usually dropped after 12 hours or so. The exact timing being determined by the type of head that had formed.

The Fuller's logs are full of information. Including complete fermentation details. And they tell you when the beer was dropped. Looking at their bog-standard X Ale, that's exactly what happened. It spent just 12 hours in the round. As did the Porter and Brown Stout. The PA stayed in the round longer, 41 hours. But the AK I have the log for was in the round 66 hours.


The fermentations for the PA and AK are quite different from those of the other beers. The majority took place in the round. About two thirds of the gravity drop was in the round. For the darker beers the fermentation had barely started when the wort was dropped into the square.

Could it be that time in the round was connected to the degreee of attenuation? The AK is the most fully-attenuated.

You'll notice that the fermentation of AK took considerably longer, despite it having a lower OG. Thirty hours longer, to be precise. Before you ask, both the X and AK were brewed at the same time of year. The AK was brewed on the 14th March 1910, the X 10th March 1910.