Saturday 21 January 2012

Proprietary yeast

Yeast. A vital element in producing beer. Larger brewers carefully nurture their strain, coddling it like a small child. Small brewers carefully choose the yeast most suited to each of their beers. In the past they were much less precious about yeast.

In London brewers' logs I occasionally come across references to other brewers yeast. Reid using Meux yeast. Or Truman using Whitbread's. The occasional reference is all it is. London brewers did borrow yeast from others, but not that often.

Go North to Edinburgh and the situation is very different. Just looking at a blank sheet in William Younger's brewing records tells you they brought in yeast more often: there's a special column to specify from which brewery:



Here's part of a Younger's log from December 1851. It covers a period of 9 days, in which you can see that they used 4 different breweries' yeast:


Haldane, Ritchie, Drybrough, and Jeffrey were the yeast suppliers. On other pages there are several others: Blair, Campbell, Bernard. I can't find any beer that was brewed with their own yeast. The Usher's logs I have show use of other brewers' yeast, though not as promiscuously as at Younger.

This page is typical. Yeast from several different breweries used apparently randomly. You'll find the same beer brewed on consecutive days but with a different yeast. Sometimes yeast from two different breweries is used for one batch. There's no rhyme or reason to it.

What does this tell us? That Scottish brewers didn't worry about having their own yeast strain. They seem happy to use any healthy yeast that happened to be to hand. Why was that? Did the yeast have so little impact on the flavour profile of the finished beer? Were all the strains of Edinburgh brewers broadly similar? Or were punters used to a bit of variation in flavour?

Or do modern brewers that make too big a deal of the strain of yeast they use? I'll have to try asking one.

13 comments:

Martyn Cornell said...

I always love (not) those popular histories of Guinness that go on about Richard (or Arthur) having a strain of yeast that went from Celbridge to St James's Gate which made Guinness so special when, in fact, Guinness took yeast from at least seven other breweries at various times in the 19th C when the strain it was using at the time became "tired".

Rod said...

"Scottish brewers didn't worry about having their own yeast strain. They seem happy to use any healthy yeast that happened to be to hand. Why was that? Did the yeast have so little impact on the flavour profile of the finished beer? Were all the strains of Edinburgh brewers broadly similar? Or were punters used to a bit of variation in flavour?

Or do modern brewers that make too big a deal of the strain of yeast they use? I'll have to try asking one"

Well, you can ask me.
In modern brewing, using the right yeast to get the flavour you want, consistantly is very important. I don't think that it is always understood that yeast is not just a catalyst which enables fermentation. Yeast can add a great deal of flavour of its own - in fact in some beers, most of the flavour comes from the yeast.
If you took the same wort, but fermented half with a standard lager yeast, and the other half with, for example, a saison yeast, you would have two very different beers.

My guess would be that the answer to your question "Were Edinburgh yeast strains all pretty similar?" is "Yes", based upon the practises that you have discovered here, unless the drinkers of these beers were prepared to accept quite a bit of variation in the taste of their beer.

Of course, yeast strains have developed a lot since 1855 too - Martyn Cornell has written a very good article about the "History of Yeast". Possibly there wasn't as much variation generally then as there is now.

Having said all that, it seems very odd that this brewery didn't have its own yeast, even just from the practical point of view - lugging all that yeast around Edinburgh would have been a pain in the neck, and increased the potential for infection.

Ron Pattinson said...

Rod, most of Edinburgh's brewers were clumped around Canongate. Not such a great distance to move yeast.

Gary Gillman said...

Possibly Younger's had had problems with its own yeast, and was using different companies' yeast until it came up with one suitable to its needs.

Why use different ones in such a short period though, why not re-pitch with the yeast saved from the Ritchie's brew, say, or Dryborough? Maybe they wanted to work out which one would remain resistant to a problem which was making the brews taste poorly. Given wooden vessels (some) and a less than antiseptic environment in modern terms, anything they used became part of their own process to a degree and maybe the flavour wasn't right until they found a brewing where the foreign yeast held up well in their brewery.

Another possibility is, the final brew in this series would likely have characteristics of all the yeasts, since some traces of each surely would linger in the wooden vessels or atmosphere of the rooms in the buildings. So maybe after 5 different yeasts and brewings, say, that was a way to come up with a new resistant yeast they could crop for the future. Anyway these must have been multistrains which could have produced tastes like some modern Belgian ales using ditto.

Gary

Gary Gillman said...

Assuming this practice continued though for months on end with no evidence their "own" yeast emerged, I'd think the reason is something to do with their yeast management system. Maybe their room where they kept jugs of yeast had become infected and they couldn't root it out, or something else to do with yeast management went awry which made them contract out its production for a lengthy period.

Gary

Rod said...

Ron
The distances involved may not be very great, but wet yeast is not a very nice substance to work with - it stains, it's clammy and all vessels used would have to thoroughly cleaned before and after. If yeast is allowed to dry onto surfaces or vessels it takes a lot of shifting. Oh, and don't get it in your eye.
The main thing is, though, that transporting it around, transferring it from vessel to vessel and exposing it to the air would greatly increase the risk of infection.

Ron Pattinson said...

Gary, the printed heading in the brewing book saying "from which brewery" is a clear sign it wasn't a short-term thing.

The Ushers logs I have, while not as extreme as Younger's, frequently mention other brewers' yeasts.

Gary Gillman said...

Ron, well in that case, I would think it must relate to some long-term problem they had to store yeast, maybe a deeply infected yeast-room (unless they were contract brewing that is?!).

I was looking up yeast management in Southby. He states that larger breweries did not need to source yeast from neighboring ones since they generally made more than one kind of beer and could interchange yeasts when one lost power. He gives an example of a brewery's stout yeast serving well for its ale production.

This is confirmed in a letter from a brewer at Spitalfields Brewery, London to (indirectly) Charles Darwin - yes the famous one. See pp 373-374 of the link below. Part of the discussion at my end is no-view, unfortunately (p. 374), but the gist follows what Southby said.

http://books.google.ca/books?id=JinoKpYo7JUC&pg=PA373&dq=spitalfields+brewery+%2B+yeast+%2B+Charles+Darwin&hl=en&sa=X&ei=dwgbT7ygN-PW0QGU9MniAw&redir_esc=y#v=onepage&q=sp

Gary

Kristen England said...

Here is the point everyone is missing. They were multi strains, not single. Not a chance to keep them separate. The strongest strain will dominate. If I have a yeast slurry, that is dropped to be pressed yeast And used by the pound I don't care what's on the outside, there are sooooo many bazillion yeast that a bit of garbage won't have the chance to take over.

Rod said...

"Here is the point everyone is missing. They were multi strains, not single. Not a chance to keep them separate. The strongest strain will dominate."

No - I think we all understood that, and Gary already specifically referred to it.
I don't much see how it changes much though - we still don't get why they were going through this most unusual proceedure, creating a lot of extra work, and a greatly increased chance of infection.

Joe Walts said...

Do these practices predate Pasteur's work with wine and beer yeasts? If so, the brewing industry may have still had a poor understanding of microbial contamination. Younger's still could have observed that their beers tasted better when they brought in new yeast, though. Maybe it was akin to today's brewers propagating new cultures every 8-10 generations. Regardless of the mixed nature of the cultures, I agree with Rod that the breweries who shared yeasts probably had pretty similar cultures. If Younger's pitched a beer with yeast from Westmalle, the resulting beer would be unrecognizable.

rncmarques said...

I am no brewer, but I am in the brewing industry, so with my limited knowledge I think it needs to come down to what you are trying to achieve. If you are a large commercial brewery doing many millions of hectolitres ayear you want consistency: across brews, months, geographical locations. Does a specific yeast strain not provide that? Repeatable flocculation (for subsequent crops), ferment times (throughput is a critical factor), conversion efficiency (cost) and then of course all the taste factors. However, if one is a local small brewery the variations may be seen as charming, such as people enjoy the fact that wine vintages are slightly different. That's my view. I blog about beer amongst other things on livedotdotdot.com.

Rod said...

"If you are a large commercial brewery....... you want consistency: across brews, months...."

Well, yes - that's the point, Younger was a large brewery. Ron has recently estimated that, in 1872 -

"Younger must have been brewing well in excess of 100,000 barrels a year."

Which I think (not good at Imperial measures) is something like 30 million pints - I'm happy to be corrected - quite a lot by comtemporary Scottish standards, I believe.

"However, if one is a local small brewery the variations may be seen as charming...."

Dead right, but that's not really what Youngers was, which makes these practises all the more difficult to understand.