Saturday 8 November 2014

Brewing in WW II (part nine)

We'll be looking at some of the less obvious difficulties faced by British brewers during WW II.

During both wars the government struggled to keep coal output at a sufficient level to meet demand. As things like kettles were generally powered by coal, a shortage of it caused acute difficulties. Even more so in breweries where everything was steam powered.

"The shortage of coal created further difficulties which were often aggravated by its poor quality. This need to conserve coal raised the question of copper boiling, and brewers found they had to reduce their boiling period almost to the limit of safety. It was also often difficult, with the low-quality of coal available in some districts, to maintain a sufficient head of steam on the boilers to obtain a suitable boiling temperature. When the coal situation became difficult brewers were asked to take the necessary steps to conserve fuel as much as possible. The experience of the last war, however, had taught them a lot about the saving of fuel, and its rising price in the intervening years had encouraged efficiency in this direction, so that there were not many improvements that could be carried out. Notwithstanding this they were subjected to frequent visits from inspectors and advisers from the Ministry of Fuel, many of whom knew little more than the theory of fuel consumption."
Journal of the Institute of Brewing Volume 52, Issue 3, May-June, 1946, pages 124 - 125.

Brewers in WW I had voluntarily reduced their coal consumption. So I can believe that most of the easy ways of cutting coal consumption had already been implemented.

Did brewers reduce boil times during the war? Whitbread certainly did, as these table show:

Whitbread Ales in 1938
Date Year Beer Style OG FG ABV App. Atten-uation lbs hops/ qtr hops lb/brl boil time (hours) boil time (hours)
23rd Feb 1938 33 Strong Ale 1061.6 1016.5 5.97 73.21% 8.47 2.23 1.25 1
25th Feb 1938 33 Strong Ale 1059.0 1016.5 5.62 72.03% 8.47 2.18 1.75 1.5
2nd Mar 1938 DB Brown Ale 1054.6 1016.0 5.11 70.70% 9.98 2.36 1.25 1.25
22nd Feb 1938 Ex PA Pale Ale 1048.1 1012.0 4.78 75.05% 7.49 1.54 1.33 1.42
1st Mar 1938 Ex PA Pale Ale 1048.3 1013.5 4.60 72.05% 7.49 1.54 1.67 1.42
21st Feb 1938 IPA IPA 1036.5 1006.5 3.97 82.19% 10.00 1.54 1.5 1.5
24th Feb 1938 IPA IPA 1037.1 1007.0 3.98 81.13% 10.00 1.58 1.5 1.5
21st Feb 1938 LA Mild 1028.3 1008.0 2.69 71.73% 7.44 0.90 1.25 1.33
22nd Feb 1938 PA Pale Ale 1048.3 1012.0 4.80 75.16% 7.49 1.55 1.33 1.42
25th Feb 1938 PA Pale Ale 1048.6 1011.0 4.97 77.37% 7.49 1.55 1.33 1.5
1st Mar 1938 PA Pale Ale 1047.8 1011.5 4.80 75.94% 7.49 1.52 1.67 1.42
21st Feb 1938 X Mild 1035.7 1010.0 3.40 71.99% 7.44 1.14 1.25 1.33
22nd Feb 1938 X Mild 1036.1 1011.0 3.32 69.53% 7.87 1.23 1.25 1.08
25th Feb 1938 X Mild 1035.3 1010.0 3.35 71.67% 7.44 1.11 1.25 1.25
Average



8.18 1.57 1.40 1.35
Source:
Whitbread brewing record held at the London Metropolitan Archives, document number LMA/4453/D/01/105.


Whitbread Ales in 1945
Date Year Beer Style OG FG ABV App. Atten-uation lbs hops/ qtr hops lb/brl boil time (hours) boil time (hours)
24th Aug 1945 DB Brown Ale 1043.3 1008.0 4.67 81.52% 6.25 1.16 1 0.75
27th Aug 1945 IPA IPA 1031.6 1006.0 3.39 81.01% 8.22 1.13 1.25 1.25
4th Apr 1945 PA Pale Ale 1039.4 1010.0 3.89 74.62% 6.03 1.01 1.08 1
24th Aug 1945 PA Pale Ale 1039.5 1012.5 3.57 68.35% 5.85 1.01 1.08 0.75
4th Apr 1945 XX Mild 1028.2 1009.0 2.54 68.09% 5.63 0.70 1 0.75
5th Apr 1945 XX Mild 1028.4 1008.5 2.63 70.07% 5.67 0.71 1 0.75
24th Aug 1945 XX Mild 1028.1 1010.0 2.39 64.41% 5.67 0.71 1 0.75
8th June 1945 XXXX Strong Ale 1043.4 1014.0 3.89 67.74% 6.44 1.19 1 1
2nd Oct 1945 IPA IPA 1031.6 1006.0 3.39 81.01% 8.53 1.22 1.25 1.5
3rd Oct 1945 XX Mild 1028.4 1010.0 2.43 64.79% 5.77 0.72 1 0.75
3rd Oct 1945 PA Pale Ale 1038.8 1011.5 3.61 70.36% 5.85 1.03 1.08 0.75
5th Oct 1945 DB Brown Ale 1043.6 1011.0 4.31 74.77% 6.25 1.18 1 1.25
19th Oct 1945 XX Mild 1028.2 1008.5 2.61 69.86% 5.77 0.72 1 1.33
31st Dec 1945 XX Mild 1027.8 1009.0 2.49 67.63% 5.77 0.68 1 1
Average 6.27 0.94 1.05 0.97
Source:
Whitbread brewing records held at the London Metropolitan Archives, document numbers LMA/4453/D/01/112 and LMA/4453/D/01/113.

For the first copper, the average boil time fell from 84 minutes to 63 minutes and for the second copper from 81 to 58 minutes. Whereas before WW I, the shortest boil at Whitbread was 90 minutes.

The reduction was even larger at Barclay Perkins:

Barclay Perkins Ales in 1939
Date Year Beer Style OG FG ABV App. Atten-uation lbs hops/ qtr hops lb/brl boil time (hours) boil time (hours) boil time (hours) boil time (hours)
19th Jun 1939 A Mild 1030.8 1007.5 3.08 75.65% 7.00 0.84 2.5 2.25 2 2
19th Jun 1939 X Mild 1034.8 1010.0 3.28 71.26% 7.00 0.95 2.5 2.25 2 2
19th Jun 1939 XX Mild 1042.7 1015.0 3.66 64.87% 7.00 1.14 2.5 2.25 2 2
20th Jun 1939 PA Pale Ale 1052.5 1014.5 5.03 72.38% 7.50 1.54 2.5 2.75 2
20th Jun 1939 XLK (trade) Pale Ale 1045.7 1017.0 3.80 62.80% 7.50 1.37 2.5 2.75 2
20th Jun 1939 XLK (bottling) Pale Ale 1035.8 1011.5 3.21 67.88% 7.50 1.15 2.5 2.75 2
21st Jun 1939 XX Mild 1042.7 1011.5 4.13 73.08% 7.00 1.18 2.5 2.25 2
21st Jun 1939 X Mild 1034.8 1010.5 3.22 69.86% 7.00 0.96 2.5 2.25 2
22nd Jun 1939 PA Pale Ale 1052.8 1018.5 4.54 64.96% 7.50 1.54 2.5 2.25 2 2
22nd Jun 1939 XLK (trade) Pale Ale 1045.8 1014.5 4.14 68.35% 7.50 1.35 2.5 2.25 2 2
22nd Jun 1939 IPA (bottling) IPA 1043.9 1013.5 4.03 69.27% 7.50 1.28 2.5 2.25 2 2
29th Jun 1939 XLK (trade) Pale Ale 1045.7 1014.5 4.12 68.26% 7.50 1.38 2.5 2.25
29th Jun 1939 IPA (bottling) IPA 1043.8 1012.5 4.14 71.48% 7.50 1.32 2.5 2.25
Average 7.31 1.23 2.5 2.37 2 2
Source:
Barclay Perkins brewing record held at the London Metropolitan Archives, document number ACC/2305/01/623.

Barclay Perkins Ales in 1945-46
Date Year Beer Style OG FG ABV App. Atten-uation lbs hops/ qtr hops lb/brl boil time (hours) boil time (hours)
7th Apr 1945 XLK Pale Ale 1035.4 1012.8 3.00 63.98% 5.09 0.75 1.5 1.5
22nd Feb 1945 XX Mild 1031.4 1009.5 2.90 69.75% 5.49 0.71 1.5 1.5
22nd Feb 1945 X Mild 1029.7 1008.5 2.80 71.38% 5.49 0.65 1.5 1.5
13th Jul 1945 XX Mild 1031.4 1010.0 2.83 68.15% 4.96 0.67 1.5 1.5
25th Jan 1946 XLK Pale Ale 1035.3 1010.0 3.35 71.67% 7.00 1.04 1.5 1.5
25th Jan 1946 IPA IPA 1031.5 1009.0 2.98 71.43% 7.00 0.93 1.5 1.5
Average 5.84 0.79 1.5 1.5
Source:
Barclay Perkins brewing record held at the London Metropolitan Archives, document number ACC/2305/01/626.

The first copper fell from 150 to 90 minutes, the second copper from 145 to 90 minutes. And while there had been up to four coppers pre-war, by 1945 there were never more than two.

The two sets of tables also show the fall in hopping rates. At Whitbread, the average hopping rate per quarter fell from 8.18 lbs to 6.27 lbs.  Or 23%. At Barclay Perkins from 7.31 lbs to 5.84 lbs. Which is s lightly smaller percentage fall: 20%

Now some research done into boiling:

"Investigations which were carried out in the method of operating the small scale brewing plant at Birmingham University for the purpose of carrying out brewing trials with the new varieties of hops grown at East Malling Research Station brought to light some interesting facts with regard to flavours transmitted to beer under different boiling conditions. It was found that the temperature at which the copper boils is an important factor, and that if the temperature which corresponds to that obtained in an open brewing copper is not exceeded, the characteristic flavour which would be expected to be obtained from a physical examination of the hops can be readily detected in the beer. When this temperature is exceeded, however, as it would be for instance if a pressure copper was used, this characteristic flavour disappeared and a dead level of flavour is obtained, no matter what hops are used."
Journal of the Institute of Brewing Volume 52, Issue 3, May-June, 1946, page 125.

That's quite an odd claim: that you got no hop flavour if you boiled at a higher temperature than an open copper. You may remember that different types of brewers used different designs of copper. In London, where Porter brewers wanted to build colour, sealed, domed coppers were used. While Burton Pale Ale brewers - who wanted to keep their beer as pale as possible - used open coppers.

Next time it's isinglass.

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