Monday, 10 October 2011

Scottish Ale brewing in the 1850's

Time for some contemporary descriptions of Scottish brewing practices. I'm starting with a relatively short one because, well, I can't be arsed to go through the long one yet. It's a complete chapter and requires a fair bit of fiddling to get into a presentable state. Maybe next week.

See if you can spot the big inconsistency:

"Ale. A well-known amber-coloured fermented liquor of considerable strength, but varying in the amount of alcohol which it contains, according to the option of the particular ale brewer. Edinburgh ale contains apparently more saccharine matter unfermented than other ales, and is strong. Burton ale has more hops added, and is hence termed pale bitter ale. The Scotch ale is said to be brewed during the cold months of the year, only one mash of half-an-hour's duration being made, and the heat of the liquor raised to 180°; it is then drained off into the wort copper. The malt is then deprived of all its soluble matter by sparging, or dashing over hot water of 180° for eight or ten times successively, the liquor draining through by apertures placed at the sides of the mash tun, and armed with stopcocks. One gallon of yeast is added to 2-10 gallons of wort, and the fermentation begun at 50°, and continued for two or three weeks: four lbs. of hops are used to the quarter of malt. The following table by my pupil, Mr. John Wright Currie, of the Perth Brewery, gives the strength of various ales brewed in that establishment. The experiments were made with great care in my laboratory.

Scottish Ales

Absol. Alcohol per cent Extract per cent Water per cent
Export Ale 7.96 3.75 88.29
India Ale 8.97 2.75 89.28
No. 3 Ale 7.055 5.7 87.25
No. 4 Ale 7.855 6.675 85.47

Scottish Ale Brewing.—To brew 20 barrels of ale, 80 bushels of malt and 80 lbs. of hops are the same time the sluice of the malt bung is opened, and the malt and remainder of the liquor at 175° run down together, and stirred. The mashing requires three hours, when the sparger (sprinkler) is fixed to the head of the tun. The sparger is a copper cylinder five or six inches in diameter, closed at both ends, and nearly so to within a foot of the centre, which is open, with a cross division against, which a run of liquor by a spout from the copper strikes and sends it round the tun. An iron bar is fixed across the latter, on which the sparger is placed on a pivot. Its two arms extend the width of the tun, the inferior side of these being pierced with small holes similar to the mouth of a watering-pan, from which as it revolves, the liquor escapes and sprinkles the mash. The water in the boiler being tempered to the heat required for sparging, (185°,) the taps of the mash tun are slacked, and the worts permitted to flow out slowly, the sparger being set in motion—this operation being merely a continuation of the mashing. I may add, that having examined most of the waters used by the Edinburgh ale brewers, I have found them all very hard waters, containing a large quantity of carbonate of lime. If any virtue is to be attributed to the water, it. may be presumed that the carbonate may act by neutralizing any acid as soon as it is formed. The 30 barrels of wort, 72 lbs. saccharine extract per barrel, are boiled for half-an-hour, and 40 lbs. hops added; another half-hour's boiling takes place, the remaining hops are added, and the wort boiled for another half-hour. Worts of the gravity of 50 lbs. extract per barrel strengthen 5 lbs. per barrel in one hour's boiling, and worts of 100 lbs. in one and a half hour strengthen 15 lbs. So that the brewer can easily judge of the amount of boiling required by the use of the saccharomcter. The worts, after a quarter of an hour, are run into the hop back, and then spread on the coolers, where they remain twelve hours; during this time they lose one-eighth of their bulk by evaporation. The worts being cooled to 53°, one barrel of wort is run into the gyle, and 6 gallons of yeast added, and thoroughly mixed; the remaining wort is then added. In Scotland, the temperature for commencing the fermentation is about 52.5°, in England 62.5°. In twenty-four hours the first stage ends, the surface being characterized on the edges by a white circle, and irregular patches of white breaking through, and soon being covered with froth. The head of froth is beat down, and the process continued for twenty-four hours more. In eight days the heat has increased 10°. The brewer judges of the period to stop the fermentation by the saccharometer, which indicates the amount of sugar which has been converted into alcohol. The next process is cleansing. In Edinburgh the ale is run finished from the gyle into the casks in which it is sold. In Alloa and Stirling it is run into butts, from which it is racked into casks, a pint of fillings or prepared wort being put at the same time into each."
"Cyclopaedia of chemistry with its applications to mineralogy, physiology and the arts" by Robert Dundas Thomson, 1854, pages 26 - 27.

Did you see it? In the first paragraph it's said that mashing only lasts half an hour in Scotland. In the second, that it takes three hours. I suppose it depends what you mean by mashing. Brewing records usually differentiate between "mashing" and "standing". The former is when the grains and water are being actively mixed. The latter, when the grains and water are left to, well, stand before the wort is run off. Mashing was rarely longer than 20 or 30 minutes, standing about two hours.

The great attention paid to sparging is because of its Scottish origin. Though by the time of this text, the 1850's, the practice had spread to England.

Let's turn our attention to the Ale breing brewed. Just 20 barrels from 80 bushels implies a gravity of 40 lbs per barrel, or 1108º. A hefty beer, then. Not sure which saccharometer the author used. 72 lbs per barrel doesn't tally with any of the scales I know.

The hopping instructions are nice and precise: one hour boil, half the hops added at the start the rest after half an hour. That's fairly typical. Most books describe two or three hop additions. A hopping rate of 4 lbs a barrel sounds like a lot. But this is a monster of a beer. That rate corresponds well with the one used in William Younger's 120/- Ales of 1858. That was 1108º and had 3.89 lbs of hops per barrel.

How does that hopping rate compare with that of similar English beers? Is it far less as we've been led to believe? Er, no. Whitbread XXX from 1850 had an OG of 1098º and 3.5 lbs hops per barrel. In 1869, Barclay Perkins XXX was 1093 and had 4.98 lbs hops per barrel. This Scottish Ale falls nicely between the two.

No refrigerators are mentioned in the cooling process. This is about the period when they were coming into use.

Then there's the pitching temperature. A clear distinction is made between English and Scottish practice, the latter being pitch 10º cooler at 52.5º F. That tallies with what's usually said about Scottish fermentations - that they were cool and slow. Do Younger's brewing records agree? Not completely. In 1851 they pitched at between 55º and 58º F, depending on the strength of the wort. The fermentation temperature peaked at 69º to 70º F.

What about English brewers? The Whitbread XXX of 1850 was pitched at 60º F and rose to 76º F. 1869  Barclay Perkins XXX was exactly the same - pitched at 60º F and rose to 76º F.

From this limited evidence, it appears that Scottish beers were fermented cooler, but not by 10º F. More like 5º F.

Beating down the head. What an odd thing to do. But William Younger did. There's a column  in their brewing records with the heading "Heats and Beats in Guile" Very poetic.

You can see why I'm having motivational challenges with regard to the much longer text describing the Scottish system of brewing. It's ten or twenty times the length of this one. Maybe next week.

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