Tuesday 30 September 2008

Brewing IPA in the 1840's

This is the earlist description of brewing IPA I've found so far. It's taken from "Scottish Ale Brewer", by WH Roberts, published in Edinburgh in 1847.


Brewing IPA
Roberts was convinced that the problems some brewers had with overattenuation of their IPA's were the result of mashing at too high a temperature. When the air temperature was 40º to 45º F, he recommended a striking heat of 168º to 170º F. For an air temperature of 35º to 40º F, the striking heat was 170º to 172º F. (Source: "Scottish Ale Brewer", WH Roberts, Edinburgh, 1847, pages 161-162.) When run down into the underback, the temperature of the wort should be 145º to 150º F. (Source: "Scottish Ale Brewer", WH Roberts, Edinburgh, 1847, page 161.)

The idea was to mash as quickly as possible, about 20 to 25 minutes if using a mashing machine. The temperature was immediately taken at various points in the mash and if the temperature was much below 145º F, hot water was added until the temperature was raised to 150º F. The mash was left to stand for between 100 and 120 minutes. (Source: "Scottish Ale Brewer", WH Roberts, Edinburgh, 1847, pages 162-163.)

Sparging should begin, according to Roberts, a minute or two before the taps were opened to draw off the wort. The water for sparging was at between 185º to 190º F. When all of the first wort had been run off, the taps were closed, but sparging continued until the surface of grains were covered "it being highly detrimental to let the surface of the goods to be dry. (Source: "Scottish Ale Brewer", WH Roberts, Edinburgh, 1847, page 163.)

Burton brewers hopped at a rate of 20 to 22 pounds of East Kent hops per quarter of malt. Brewers elsewhere used rather fewer hops, 16 to 18 pounds per quarter. (Source: "Scottish Ale Brewer", WH Roberts, Edinburgh, 1847, page 164.) That's considerably more than for other styles of the period - the weaker Ales had around 8 pounds per quarter, Porter about 12 pounds.

If 22 pounds per quarter were being used, 6 pounds of hops were added to the first wort at the beginning of the boil. After 20 minutes, another 8 pounds were added and the boil continued for another 50 minutes. The first wort was transferred to the hop back and the second wort boiled with the remaining 8 pounds of hops for two hours. The hops from the first wort were left in the hop back and the second wort drained through them to drive out the first wort that had been soaked up by the them. (Source: "Scottish Ale Brewer", WH Roberts, Edinburgh, 1847, pages 164-165.)

Roberts reckoned 22 pounds per quarter was too much. He claimed to have brewed beers with far fewer hops that were still good after 5 years. He even heated them up to 90º F to see how well they withstood hight temperatures.(Source: "Scottish Ale Brewer", WH Roberts, Edinburgh, 1847, page 165.)

"Reducing the temperature of worts in the coolers is now generally accomplished by artificial means, and with great rapidity, it being important that they should be reduced to the pitching temperature, with as little delay as possible." (Source: "Scottish Ale Brewer", WH Roberts, Edinburgh, 1847, pages 165-166.)

Yeast was pitched at when the wort was between 58º and 60º F, depending on the air temperature. The fermentation was swift and vigorous, with the wort remaining in the tuns just 24 to 30 hours before being cleansed. During this time the temperature of the wort rose about 7º F. (Source: "Scottish Ale Brewer", WH Roberts, Edinburgh, 1847, pages 166-167.)

Cleansing took place in puncheons, which were filled up with ejected wort every two or three hours. Roberts warns of the dangers of filling up with wort that is cloudy, as it will just extend the cleansing period and create more work. Fermentation in the puncheons continued for 14 to 20 days, after which time the beer, which was already quite clear, was racked into hogsheads. When any head had subsided, a pound of hops was put into each hogshead which was then bunged down. (Source: "Scottish Ale Brewer", WH Roberts, Edinburgh, 1847, pages 167-168.)

Roberts mixed the hops with a little boiling strong Ale wort, which was left to cool and then added to the hogsheads. (Source: "Scottish Ale Brewer", WH Roberts, Edinburgh, 1847, page 168.)

While Roberts preferred racking when the beer was relatively clear, some other brewers deliberately racked some of the dregs with the beer. They argued that this helped the preserve the beer during the long voyage to India. (Source: "Scottish Ale Brewer", WH Roberts, Edinburgh, 1847, pages 168-169.)

7 comments:

Zythophile said...

My own copy of the Scottish Ale-Brewer is the 1837 version, which doesn't mention IPA at all, something that confirms my growing suspicion that IPA didn't take off in the UK generally until around 1840 - it would be interesting to know in which edition of the Scottish A-B between 1837 and 1847 Roberts felt obliged to start giving instructoions on brewing IPA. Does your copy carry an edition number, Ron?

Anonymous said...

"20 to 22 pounds of East Kent hops per quarter of malt."

what is the conversion rate for lbs per barrel or ounces per gallon?

Thank you

Kristen England said...

David,

Depends how many quarters of malt were used for a beer. The more for the same volume equals a higher starting gravity. You are comparing two different things.

There is about 31 gals in a barrel and 16oz per pound so you would multiply the hops by ~0.79.

Same reasoning you can convert qtr's to pounds (~326#/pale, 244#/brown I believe)

Andrew Elliott said...

I believe it was actually 36 gallons per British beer barrel.

You should probably check out Zythophile's (Martyn Cornell) book -- "Amber Gold & Black." In the gloassary he spells out what a quarter is: "a volume measure of malt equal to eight bushels..." I would venture to guess that for IPA, the malt would generally be Pale Malt? So about 326# / qtr of malt. Modern extract % (coarse grind) is about 80%, so that gives us about 260.8lb of fermentables in the grain, but likely a lot of that would've not been extracted, so I'll multiply by 72% for about 235lb of sugars.

Gravity will depend on how much water is used for the mash & sparge; to hit the "average" of 1.068 (16.59% Plato) we would need:

lb_sug/(lb_sug + lb_wat) = P
235/(235 + lb_wat) = .1659
lb_wat = 1182 lb
= 141.7 gal (@8.337lb/gal)
= 3.9 British beer barrels (probably 4 barrels when all said and done)

So, now we have 20 to 22lb of hops per 4 barrels, or 5-5.5lb per barrel. Comes out to 2.2-2.4 oz/gal.

TMI???

Andrew Elliott

Anonymous said...

Thank you very much andrew

Andrew Elliott said...

I guess I forgot to mention some other details that may prove important if you were trying to brew a batch using this information: you will need to consider that these are whole flower hops, and in addition to that, storage of these hops may not have been optimal, resulting in a substantial loss of alpha acids and volatile aromatics -- hence the seemingly large amount of hops being employed (vs. contemporary usage).

Ron, it may be interesting to see what info you may turn up regarding hop storage, use, and measurement (of alpha or whatever else). Perhaps another chapter of your book? I'm really looking forward to it!

Anonymous said...

Andrew-

My calculations show a slightly different conversion from lb/bbl(UK) to oz/gal(US).

Example:

For 5 lbs of hops/bbl:


5 lb/bbl(UK) * bbl(UK)/36gal(UK) * 1.2gal(UK)/gal(US) * 16oz/lb = 2.66 oz/gal(US)

For a typical 5 gallon homebrew batch, that's over 13oz of hops! Figure a high hop beer could have 10 lb/bbl and that translates to over 1.5 lbs of hops used in just 5 gallons of beer.

Holy crap that's a lot of vegetal matter in the boil!