Boil times had been declining since the end of the 19th century. There were various reasons for this. The most obvious was simple economy: the shorter the boil, the less fuel used. Which brings us to the second reason: two world wars. Brewers were compelled to economise on their use of coal, leading to shorter boils.
You can see proof of the third reason in the table below. With the reduction in gravity, there was no real need for long boils to concentrate the worts. And which are the only beers with long boils? Final Selection and Gold Label. Two unusually strong beers.
Other than that, there’s nothing really longer than 90 minutes. And most of Whitbread’s boils were little more than 60 minutes.
|Boil times 1968 - 1975|
|Year||Brewer||Beer||Style||boil 1 (hours)||boil 2 (hours)||boil 3 (hours)||boil 4 (hours)|
|1973||Whitbread||Gold Label||Barley Wine||3||3|
|1972||Whitbread||Final Selection||Strong Ale||2||2|
|1975||Elgood||Elgood Bitter||Pale Ale||1.58|
|1968||Fullers||London Pride||Pale Ale||1.25||1.25|
|Boddington brewing record held at Manchester Central Library, document number M693/405/134.|
|Whitbread brewing record held at the London Metropolitan Archives, document number LMA/4453/D/09/141.|
|Truman Ale book held by Derek Prentice.|
|Elgood brewing record held at the brewery|
|Fullers brewing record held at the brewery|