Saturday, 14 May 2011

Messrs. Salt and Co. (part three)

Bet you thought I'd forgotten my promise of a third instalment about Salt. I hadn't, just been preoccupied by other things.

We've come to one of the most exciting phases of brewing Pale Ale: fermentation and cleansing. The latter process appears to have pretty much disappeared from British brewing, with the exception of Marstons. Odd, seeing how important it was to Victorian brewers. Removing as much yeast as possible was seen as an essential part of brewing good-quality beer.

"Leaving this place behind us, we made our way to the fermenting department, which, within the last few years has been considerably enlarged, and the number and size of the squares increased to a very great extent. The room we first entered is upwards of 80 feet long, and contains eighty fermenting squares, each of forty barrels content; the next is much smaller, and holds a few other fermenting vessels. The process of fermentation is a most delicate one, and the greatest attention has to be paid to the heat at which the wort is "pitched " or run into the squares, and also to the quantity and quality of the yeast used for starting the fermentation. It is at this stage, too, that Her Majesty's representative is more than usually attentive, and keeps a strict check on the operations of the brewer — the excise charge being calculated on the gravity of the wort found in each square just before fermentation sets in. After fermentation is finished in these rooms the ale (as it is now called) is passed down by huge mains to the union room, where the "cleansing" process  goes on, and  the ale becomes thoroughly bright.

Following our guide, we came to the great union room, as it is designated, owing to the fact that a few years since it was nearly doubled in size, and now measures 170 feet square. It contains 864 union casks, each of which cleanses 150 gallons of ale at one time. This place, with its beautifully clean floor an well arranged appliances, is as attractive as any similar room in Burton. After being thoroughly cleansed in the union casks, the ale is run into racking squares that are placed on the floor below, from whence it is racked into the trade casks. The racking room, which we afterwards visited, contains twelve racking squares, each holding 120 barrels, and its enormous roof is supported by no less than 200 iron columns of ponderous size We need scarcely add I that the most scrupulous cleanliness is observed in every part of the brewery, and that after use every brewing vessel and utensil is thoroughly washed with hot or cold water, as may be necessary."
"Noted Breweries of Great Britain and Ireland, vol. 2", Alfred Barnard, 1889, page 122.

I'd already realised how careful brewers - and not just those in Burton - were about pitching temperatures. The consistency of the temperature made that clear. It rarely varied by more than half a degree Fahrenheit. And it wasn't just the pitching temperature that was carefully monitored. The temperature was controlled right through the fermentation through the use of attemperators fitted inside the fermenting vessels.

Here's an example from Barclay Perkins, a PA brewed in 1886. It was pitched at 60º F. After a day, the temperature had risen to 65º F., and after 2 days to 71º F. By the the time primary fermentation was complete, after 5 days, the temperature had dropped back down to 62º F.

This is a more detailed example from Fuller's:

11th March 1910 Fullers PA
hours temp. gravity
0 59.5 1052.6
19.5 62 1049.6
22.5 63.5 1047.6
29 69 1042.7
40 69 1029.4
41.5 Dropped into square
43.5 69 1025.5
47 Collected
51 69 1018.6
54 Skimmed
60 69 1013.9
67.5 69 1012.2
86 68 1011.1
94.5 Liquor on
158 58.5 1012.2
Fullers brewing records

"Liquor on" signifies pumping cold water through the attemperator, in this case to bring the temperature down before racking.

The 80 squares of 40 barrels each could have held a total of 3,200 barrels. As beer wouldn't sit in the square for more than a week, that's a potential fermentation capacity of at least 166,400 barrels a year. The 864 union casks, each holding 150 gallons, had a similar capacity to the squares: 3,600 barrels.

Burton brewers were amongst the first in the country to have fully equipped laboratories. It was a development that helped improve beer quality and boost the reputation of Burton.
"The chemical laboratory, which is under the control of Mr. Adrian J. Brown. F.I.G, F.C.S., next claimed our attention. It is conveniently situated by the  side of the brewers office in the main building, and consists of two rooms. the larger being used as the working laboratory, the other being reserved for delicate instruments and for microscopic work.

Here, not only are the brewing waters and malt and hops submitted to careful chemical examination, but the biological examination of their product — "Beer" — during, and after, manufacture is carried on in a most systematic manner. By the aid of the microscope, "forcing" trays, and other means, biological work now occupies a very prominent part in the brewers' laboratory, and promises year by year to become more important; as the studies in this and other laboratories at home and abroad, throw more light on the growth and changes of the different species of yeasts and other microscopic plants, that play such an important part in the manufacture of beer."
"Noted Breweries of Great Britain and Ireland, vol. 2", Alfred Barnard, 1889, pages 122 - 123.
Forcing was a method used to quickly spot potential problems in a batch of beer. A sample of the beer was heated to make apparent any infection. And yeast was studied under the microscope to make sure it was healthy and untainted by bacteria.

I'm still not done with Salt. Next we'll see what happened to their beer after in left Burton.

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