"A description of the malting and brewing establishments of Messrs J. Jeffrey & Co., of the Heriot Brewery, will convey some idea of the mode in which an extensive business of this kind is carried on. The malting premises, bottling-house, and ale stores of this firm are at Roseburn, at the extreme west end of the city, while their brewery is in the Grassmarket. This separation is a considerable inconvenience; but as the brewery, by repeated extensions, occupied every inch of available ground, it became imperative, when further extension was required, to sever the connection between the malting and brewing departments. Accordingly, a year or two ago, the firm acquired a site at Roseburn, adjoining the Caledonian Railway, and erected thereon malting premises and stores of great extent, and fitted up in the most complete manner.If you look at the map above (from the 1890's) you can see how the Heriot Brewery had no room to expand in their city-centre site. It looks very cramped.
. . . . . . . .
The Heriot Brewery has been in operation for a century, and for upwards of thirty years it has been in the possession of Messrs Jeffrey. Like most works which have been gradually extended from small beginnings on limited sites, the brewery is not arranged according to modern ideas of such, establishments; but that drawback apart, the place is complete in all its appointments, and the more recent additions have been made according to the most advanced views of the business. The malt is raised to a large store-room on an upper floor, and thence it is withdrawn to supply the mill. The latter consists of a pair of steel cylinders which bruise the malt—bruising being preferred to grinding, which would make the malt become pasty when mixed with water. From the mill the malt descends to the mashing-room. A new mode of mashing recently introduced is here at work. Formerly the bruised malt was placed in the mash-tun with a certain quantity of hot water, and there stirred about by revolving rakes till all the saccharine matter was dissolved. By the new method the malt escapes from a hopper into a horizontal cylinder having a series of revolving arms inside. At the same time the proper supply of water is allowed to flow in, and, as the malt and water pass through the cylinder, they are so completely mixed that they require no further mechanical treatment for the production of " wort," as the extract of malt is called. The mash-tuns are fitted with false bottoms, through which the liquid percolates, leaving the malt behind. The wort is drawn off into large vats called " underbacks," situated beneath the mashtuns, and fresh water, at a higher temperature than that first used, is run upon the malt. This is styled the " second mash," and it is effectual in extracting a further quantity of sugar from the grain. The produce of those two mashes is mixed, but that of a third mash, which is sometimes made, is kept apart and used either in brewing small beer or in treating the malt in a first mash. The residue of the malt, under the name of " draff," is used as food for cattle.
The wort having been reduced to the proper strength, is pumped from the "underbacks" to the boiling-house, which is occupied by two copper boilers, each capable of containing 5500 gallons. At this stage the hops are added according to tho kind of beer that is being made. The proportion of hops varies from 4 to 14 lb. to the quarter of malt. The boiling is continued until the aromatic and bitter principles of the hops have been extracted, and the liquid has been concentrated to the required degree. A tap in the bottom of the boiler is then opened, and the liquid is run off into the " hop-back," a large iron cistern with a perforated bottom. As the wort percolates through the bottom of the cistern it runs into the "coolers," shallow troughs of iron covered with a roof but open at the sides. There the liquid cools rapidly, but not so rapidly as desired sometimes, and means are taken by fans and other contrivances to send currents of air over the surface. Systems of tubes called "refrigerators" are also used. The tubes are arranged in the form of a vertical screen, and as a current of cold water flows through them, the wort is poured over them from above, and allowed to trickle from one to the other. If the cooling be not effected rapidly, the sugar in the wort becomes partially converted into acetic acid, and the quality of the beer is thereby deteriorated. When the liquid has been cooled down to about 60° it is ready for the next process, which is fermentation. The apartments in which the process is conducted are called tun-rooms, and each contains a dozen large tuns or vats ranged along the sides. The tuns are capable of holding 2000 gallons each. When the tuns are filled yeast is added to the wort, in order to start the fermentation. In a short time carbonic acid gas is evolved, and the liquid becomes covered with froth. The gas is so abundant that it becomes dangerous to breathe over the tuns. Even after the vats have been emptied the gas hangs about, and workmen entering them without first ascertaining whether the fatal gas had disappeared have fallen victims to their negligence. Great skill is required in determining the temperature to which the wort should be reduced before adding the yeast. In summer it is usual to cool it to some twenty degrees below the temperature of the tun-room, while in winter it is worked at several degrees above the temperature of the room. For the proper modification of the temperature the tuns are fitted with tubes inside through which warm or cold water may be made to flow. The pale amber colour and mild balsamic flavour which characterise Scotch beer are owing in some degree to the low temperature at which it is fermented. The process of fermentation is completed in from three to eight days, and then the yeast is skimmed off and the beer "cleared" by being subjected to a filtering and settling process, which removes all traces of fermentation. That completes the manufacturing operations, and the beer is run into casks, and either sent out to order or stored. The stock of porter is kept at the brewery in great vats upwards of twenty feet in depth, but the ale is stored at Roseburn. All varieties of beer, ale, and porter are made by processes similar to those above described. The liquor may differ in strength according to the quantity of water used, or in colour from the malt being more or less charred in drying.
"The industries of Scotland: their rise, progress, and present condition" by David Bremner, 1869, pages 438 - 441.
The "horizontal cylinder" described sounds like a Steel's masher, invented in the 1850's. So it was relatively new technology when this piece was written. Though the author says the mash "requires no further treatment" many breweries retained the old internal rakes to dislodge stuck mashes and for mixing water added through the underlet part of the way through the mash.
That's odd. He describes a second and even sometimes a third mash.That's not my understanding of Scottish brewing practice. I thought Scottish brewers had switched to a single mash followed by a sparge several decades earlier. Did Jeffrey continue with the old technique longer than their colleagues?
"treating the malt in a first mash". I think this means using the return wort as the brewing water in a subsequent brew.
Draff - remember that? It's what the poor woman who was mangled by machinery at George Younger's brewery had come to collect. Spent grains is the English term.
The hopping rates per quarter at William Younger in 1869 were:
6-8 lbs for Mild Ales,
12 lbs for Pale Ales,
7-12 lbs for Strong Ales
8-12 lbs for Stout
16 lbs for Table Beer.
5-15lbs for Stock Ales.
Pretty much in line with what's quoted here.
The brewery was fitted out with the latest kit, as is indicated by the use of refrigerators as well as the flat open type of cooler.
Time for my arithmetic exercise. 2000 gallons is 57 barrels. Not huge, but not an unusual size, either. Again a few details would be useful. Like how many tun rooms there were. Assuming at least two, 24 times 57 is 1,368 barrels of capacity. Three to eight days for fermentation, so let's say each vessel could be used once a week on average. Multiply that by 52 and you get 71,136 barrels annual capacity. Making Jeffrey a reasonably-sized brewery. In 1869 1,089,000 barrels were brewed in Scotland. If Jeffrey really brewed 71,136, that would have been 6.5% of the total.
Twenty degrees below ambient temperature seems pretty cool. I can't imagine the tun room got above 70º F even in the hottest summer weather. It implies pitching at 50º F or less. It would have been better if the author had given specific temperatures.
There's even a description of Scotch beer: "pale amber colour and mild balsamic flavour". Now I just have to work out what he means by balsamic. To me it just conjures up posh Italian vinegar. I'm certain that's not right. Not sure what the cool fermentation temperature has to do with the colour.
Sounds as if some beer was sent out as running beers and some other kept as Stock Ale. And they were vatting Porter. Though Porter never seems to have ever been that popular in Scotland.
The fun's not quite over yet. There's still the bottling department to come. Perhaps tomorrow. I've not decided yet.