Thursday 1 September 2016

Was Scottish Ale fermented like Lager?

One of the many dodgy claims made about Scottish beer is that it was fermented at a near Lager temperature. Apparently the near-freezing climate of Scotland is the reason.

I’m sure this misapprehension is partly based on just looking at pitching temperatures rather than the actual fermentation temperature. Because they didn’t pitch at a certain temperature and hold the wort at that for the whole duration of the process. Brewers both sides of the border did something more complex.

Usually the temperature rose quickly in the first day or two, then, through use of attemperators,  was held at a certain point for a while, then dropped down again to around or just below the pitching temperature. The maximum fermentation temperature was usually at least 10º F higher than the pitching temperature.

Another factor helping deceive about fermentation temperatures is the strength of many Scottish beers in the 19th century. The stronger the beer, the lower the pitching temperature, as more heat will be generated during the fermentation. Many Scottish beers were pitched at 54º - 55º F because they had OGs over 1100º.

I just realised that I had a wonderful example of how Scottish Ales weren’t fermented like Lager. Because I’ve got examples of both right next to each other in one William Younger brewing record from 1880:


This shows the fermentation record of three beers, XP, PX and XP. XP being a Pale Ale and PX a Pils. The top two rows are for one XP brew, the last two for another XP with the PX in the middle row.

The XPs were pitched at 59º F and 58.5 º F, when the gravity was 1053º. The PX was pitch at 54º F, gravity 1058º. The columns that follow are a temperature followed by the gravity. The temperature of the two XPs rises to a maximum of 70 º F and 68º F before falling again.

The process for PX is very different. The temperature falls immediately to 45º F, then to 41º F. It stays at 41-42º F for the next couple of weeks as the fermentation slowly progresses. All three beers were brewed on 11th April 1880. The two brews of XP were both racked of the 18th April, a fermentation of 8 days. The PX wasn’t racked until 3rd My, a total of 23 days.

Even though the XP and PX were pitched at quite similar temperatures, the process of the fermentation was totally different. The Pils was fermented much, much cooler and more slowly that the XP.

The answer to the question in the title: no. Not even vaguely

8 comments:

Marquis said...

Ron, although the Scottish climate can be very cool, the brewing centres are Edinburgh and Alloa , both coastal towns thereforee at sea level and moderated by the sea.
Climate records show that Edinburgh and Burton are within a degree or two of each other throughout the whole year.

Anonymous said...

Don't you feel any shame at all for removing the veil of fantasy from brewing history and replacing it with historical proof and certainty?

There are brewers, beer writers and beer drinkers who have created this alternate history to make themselves look very clever indeed and here you come and embarrass them with researched FACTS.

I just don't know what to think about your behaviour.

*I do really- keep the facts coming to embarrass the bullshiters ;)*

Anonymous said...

I had a pdf on my broken PC from a tour of the caledonian which said if it got too hot or cold they'd just add temperature adjusted water to hit the right range. Although, someone did an article on it here recently which shows pipe cooling loops in the open fermenters so I doubt that's true any more.

https://www.diffordsguide.com/producers/855/caledonian-brewery-company-limited

Ron Pattinson said...

Anonymous,

that sounds like someone getting it wrong on th tour. They probably meant water at an appropriate temperature was pushed through the attemperators - which is what the tubes inside the fermenter are called. It was the standard waay of cooling wort during fermentation.

Anonymous said...

I assume this is the kind of article you're reacting to:

http://allaboutbeer.com/article/scottish-ales/

I was once in a barn in the middle of winter in Northern Michigan, and it was reasonably warm due to all of the accumulated body heat of the animals. It's hard for me to imagine that there would be any trouble maintaining warmth in a building with a big active fermenter even when outside temperatures were around 40F, unless they were going out of their way to circulate outside air into the building. I suppose it's possible to ferment that way, but it's hard to see why it would be a natural thing to do.

Anonymous said...

Hi Ron, I agree with you.

I couldn't find the pdf but I found the article from 2006. Here's the snippet:

The fermentation takes place on a rigid one week schedule. If the fermentation is too slow, the brewer may add hot water to raise the fermentation temperature, or cold water if it is too fast. Krausen is skimmed three times during this period. Once fermentation is complete, a World War II-era yeast press (they were expecting delivery of a new one just a week after our tour) is used to remove additional unwanted yeast from the beer. The yeast sticks to the sheets in the press; the sheets are removed and the yeast is scraped off and tested for viability and accordingly either re-used or tossed out.


http://browsingbrews.blogspot.co.uk/2006/11/tour-of-caledonian-brewery-edinburgh.html

Anonymous said...

Oops, looking at the top they toured in 1996!

Ron Pattinson said...

Anonymous,

exactly that type of article. All totally wrong.