Saturday, 18 December 2010

Milling, mashing and boiling at Bass

Back to Bass. The brighter amongst you may have guessed what I'm up to. We're going to take a look at some of the most vital brewing processes: milling, mashing and boiling. Courtesy of Alfred Barnard, chronicler of Britain's late-Victorian brewing industry.

I'm so glad I've all four volumes of "The Noted Breweries of Great Britain and Ireland". It allows a glimpse inside all the great, and some not so great, breweries of the period. Not that I have the physical books. They are way too expensive, even for a booky spendthrift like me. I picked up a version on CD. At 25 euros, one of my best bargains ever.

But we're here to discuss Bass, not my book-buying adventures. Time for the big, long quote that will spare my typing fingers.

"He has a large staff of first, second brewers and juniors, under his control, and all the operations in his department are carried on with precision and regularity. Mr. W. O. Moody, one of his lieutenants, conducted us over the brewery, and first took us to the malt-rooms referred to, measuring 70 feet long by 27 feet broad, containing two mills, with a double set of rollers to which is attached, immediately above it, a screening machine divided into three trays or partitions, like one we saw in the Old Brewery, but omitted to describe. The first tray separates any odd bits of straw or wood that may have collected in the malt during its transit from the makings; the second separates the large grains from the smaller; whilst the last sieves the combings, which latter fall into a dust-chamber below, while the former drop through their respective rollers to be crushed. Progressing a short distance, we came to the No. 2 mill-room, not quite so large as the first, also containing a double-set of malt mills similarly fitted with screens, etc In both cases, the crushed malt falls into an elevator that lifts it to the screw connected with the hoppers over the mash tuns. The elevators here, as in all the other breweries of this firm, are enclosed in iron frames, and not timber as in some places. As we entered the adjoining room, our attention was given to seven inverted octagonal hoppers, which spring from the floor and cover the whole surface of the chamber; taking a peep inside from an elevation, we observed that each is divided into six outlets or funnels, to distribute the grist thoroughly over the bottom of the mash-tuns. To visit these, we followed our guide down the main staircase, which brought us to the mashing room as this noble gallery is called. It is 156 feet long and 24 feet broad, and contains seven mash tuns, with covers constructed of teak and oak, enclosing timber revolving rakes and sparging apparatus, and each tun is capable of mashing sixty quarters at one time.

We noticed that fire mains run through every part of this, and all the other buildings; they rest on iron brackets affixed to the walls, possessing at intervals of a few feet, stop-cocks for attaching the fire-hose, which is kept in a recess on every floor. Wishing to keep the whole process in view, and follow its course, we accompanied Mr. Moody across the bridge to the second mash tun stage, also on the first floor in the next block, not quite so large as the one wc had left, 114 feet long by 27 feet broad, containing five mash tuns with hoppers above exactly the same as the others. The floors, which are of slotted timber, are easily cleaned, and are constructed so as to give extra light to the floors beneath. We then recrossed the bridge and proceeded to the copper hearth, on a level with the third floor of the first building. Its length is 165 feet by 48 feet, and it is built up 42 feet from the ground on solid brick foundations. This construction is a marvel of strength and solidity ; both of which rendered necessary when one considers the enormous weight it has to bear and the amount of strain put on it by the action of boiling in the coppers. It contains three iron water coppers, dome-shaped, each capable of holding 300 barrels, and eleven wort coppers each of fifty barrels content. All are heated by large furnaces and the latter are constructed of copper. We passed down the long avenue which divides them, to see the process of hauling up the coal to this altitude. It is lifted in small trucks by very powerful hydraulic lifts, and the trucks are run to the doors of the furnaces. The floor above is of pierced metal plates, not only to give extra light, but to enable the workmen to communicate with each other during the various operations of boiling the worts and adding thereto the hops. We climbed a steep iron ladder to take a peep into the heads of these coppers, and see the brewers throw in the hops. At the moment they joined the boiling wort a most refreshing fragrance filled the place, and long before we left this part of the building it had increased our appetite to a wonderful degree. While perambulating this department, our attention was called to the water tanks in the roof of the malt hopper room to which we climbed. One tank contains Shobnall water, another cooling water, and a third water from the wells in the New Brewery yard. Here, also, we noticed that the roof of the copper hearth is also utilized, as in it are placed two receivers into which the wort is pumped direct from the under-back, running, from thence, by gravitation, into the coppers below."
"Noted breweries of Great Britain and Ireland, Vol. I" by Alfred Barnard, 1889, pages 71 - 73.

A sixty quarter mash tun, assuming a yield of around 85 lbs per quarter and a gravity of 1064, will produce around 220 barrels of beer. Which means the 300-barrel coppers were about the right size to provide the mashing liquor for one complete brew. At just 50 barrels, the wort coppers seem rather small. A mash would produce three or four worts of differing strengths. Assuming there would be about 250 barrels of wort pre-boil, that would fill five coppers. In the 1880's, Barclay Perkins used 4 coppers of around 320 barrels capacity to brew 1,000 barrels of beer. Based on that, you would expect Bass's coppers to have been around 75 barrels.

While we're on the topic of coppers, Barnard doesn't make it clear if they are closed or open. They do appear to be direct-fired, which is a bit of a surprise. By this time many breweries were using closed, dome-shaped, steam-heated coppers.

"Fire-coppers are built over a brick furnace; the lower end is pan-shaped. Half-way up it widens out slightly, thence to the top the sides are vertical or sloping. The old-fashioned coppers are open, but in many breweries they are closed, and the contents are boiled under a slight pressure. Some brewers prefer to boil pale ale worts in open coppers."
"The Brewing Industry" by Julian L. Baker, 1905, page 88.

I wonder if that was true? And if it was, I wonder what the reason might be for boiling Pale Ale in an open copper?

Now on to the mash tuns. From the description of the funnels to distribute the grist evenly over the mash tun floor, it doesn't sound like they were using a Steele's masher (a sort of screw that mixes hot water and grain together as they enter the mash tun). Timber rakes? Never heard of that before. I thought internal mashing machines were always made of metal.

And finally the water. The fact that they used different water for brewing and cooling. I can imagine that the very hard water used to brew might not have been all that suitable for other purposes. The supply of brewing water was, I suppose, also limited.


Ryan said...

Paler malts have more of the precursor for DMS, the open coppers might have helped boil off more S-Methylmethionine

Adrian Avgerinos said...

Yup. I was going to say the same. Keep the lid on and your boiled wort will taste like creamed corn.