I expected to see boil times shortening in the later war years as brewers tried to reduce their coal usage. Which was something they had agreed with government.
No evidence of that at all at Fullers:
|Fullers Brown Stout boiling 1910 - 1920|
|Date||Year||boil time (hours)||boil time (hours)|
|Fullers brewing records held at the brewery.|
While Courage only reduced their boil times after all the nastiness was over.
|Courage Double Stout/Stout boiling times 1914 - 1920|
|Date||Year||Beer||boil time (hours)||boil time (hours)||boil time (hours)|
|21st Oct||1914||Double Stout||2||2||1|
|10th Mar||1915||Double Stout||1.5||2||1|
|22nd Sep||1915||Double Stout||2||2||1|
|1st Dec||1915||Double Stout||2||2||1|
|10th May||1916||Double Stout||2||2||1|
|3rd Jan||1917||Double Stout||2||2||1|
|24th Oct||1917||Double Stout||2||2||1|
|16th Jan||1918||Double Stout||2||2||1|
|Courage brewing records held at the London Metropolitan Archives, document numbers ACC/2305/08/247, ACC/2305/08/248, ACC/2305/08/249, ACC/2305/08/250 and ACC/2305/08/251.|
That’s another theory kicked into touch. Hang on. Let’s take a look at Whitbread.
|Whitbread London Stout boiling times 1914 - 1920|
|Date||Year||Beer||boil time (hours)||boil time (hours)|
|17th Mar||1914||London Stout||1.75||1.75|
|12th Jul||1915||London Stout||1.75||1.75|
|15th Nov||1916||London Stout||1.5||1.75|
|21st Oct||1918||London Stout||1.5||1.5|
|23rd May||1919||London Stout||1.5||1.5|
|9th Jan||1920||London Stout||1.5||1.75|
|Whitbread brewing records held at the London Metropolitan Archives, document numbers LMA/4453/D/09/108, LMA/4453/D/09/110, LMA/4453/D/09/111, LMA/4453/D/09/112 and LMA/4453/D/09/113.|
Pretty clear that Whitbread reduced their boil times by 15 minutes in the middle of the war. And then bounced them back a bit after hostilities ended. At least one brewery cut down on their boiling, then.
This is an excerpt my book "Stout!"