Tuesday 5 April 2011

Brettanomyces and Pale Ale

This is a question that's troubled me for some time: did long-matured Pale Ales contain brettanomyces?

Looking at it logically, it seems quite likely. I know many English pitching yeasts contained brettanomyces. In running beers, they wouldn't have been apparent as the beer would have been consumed long before they could have made their presence felt. But Pale Ales were Stock Ales, matured, as we've learned for up to 12 months in the barrel.Plenty of time to affect the beers flavour.

Then there are the union sets. A perfect place for brettanomyces to hide with all that wood and piping.Even if the pitching yeast contained no brettanomyces, there's a good chance a Pale Ale would have picked it up from the unions.

Then there are the descriptions of Pale Ale picking up its distinctive flavour only after a long maturation. You know what that screams at me? Brettanomyces. What else takes so long to develop?

I've lots of analyses of 19th century Pale Ales. But they aren't much help. Brettanomyces wasn't identified until just after 1900. So no hard evidence, just guesswork and supposition. And you know how keen I am on that as a research method.

Until a few days ago. When my latest book purchase flopped onto the doormat. "Onderzoekingen over het Gistgeslacht Brettanomyces" ("Investigations into the yeast species Brettanomyces".) As far as I know, it's the only book about brettanomyces. Weird that it's in Dutch. Luckily, that isn't a problem for me.

I found out about the book from "The Brewers' Journal" for 1940, which contains a review of it. You can probably guess what followed. I did a search in Abebooks and located a copy. (And there was only one, so bad luck if you'd like your own copy.)

I wondered if it would have anything about Pale Ale. I wasn't disappointed. That's putting it too lightly. I hit the jackpot. Not only was a Pale Ale analysed, but it was the most renowned of them all: Bass Pale Ale.

As already noted, Brettanomyces yeasts also play a role in the fermentation of English beer types "ale" and "Stout". Maturation does not, as with "lambic", take place in bottles but only in barrels. However, these are also bottled unfiltered. I examined samples bottled in this country of "Pale Ale" and "Stout" from Bass & Co., Brewers, Burton on Trent. For isolation of Brettanomyces strains from these samples a portion of the sediment was swabbed on malt agar and chalk plates and yeast-agar-glucose and chalk plates, which were incubated at 30° C.

After two days, several yeast colonies were observed, but which did not appear to form acid. After 7 days between these, very small colonies were visible, which dissolved the chalk around the colony. On the plates from the "Stout" two types of acid-forming colonies were distinguished, hard and soft. The majority were hard, and under the microscopic these were all found to be identical to each other. A hard and a soft colony tubes were scraped off into test tubes and then isolated into a pure culture in the way described for "lambic". The soft culture we will call for the time being St. I and the hard St. II.

On the plates on which were spread the dregs of "Pale Ale". only the hard acid-forming colonies could be isolated. These were apparently identical with St. II. In this context it should be remembered that the beers came from the same brewery.
"Onderzoekingen over het Gistgeslacht Brettanomyces" by M.T.J. Custer, 1940, page 27. (My translation.)

Did Bass Pale Ale contain brettanomyces? Yes it did.

But it's more interesting than just that. Did you notice that the Stout contained two different types of brettanomyces, but the Pale Ale just one. That implies that one of the types almost certainly wasn't in the pitching yeast. Unless the Pale Ale and Stout were pitched with different yeasts.

There were differences in the way Bass made their Pale Ale and Stout. Pale Ale was matured in carriage casks, Stout in vats. Had the Stout picked up the soft St. I type from the vats?

There are still lots of unanswered questions. But one thing we know for sure: Pale Ale did sometimes contain brettanomyces.


Ed said...

Excellent work Ron - keep it coming! I've started brewing with Brett. recently and there's very little information out there about them.

Gary Gillman said...

That's very helpful and the more I think about it, the more I believe Orval is close in taste to some of those brett-influenced pale ales. Orval has a notable earthy/barnyard/estery taste from brett and also multiple fermentations (which characterised beers long held in wood - not the same but similar). It was devised at a time pale when pale ale had world reputation for quality.

I find the brett influence in Orval quite strong. Perhaps if you combined it 50/50, say, with Worthington White Shield (no brett) you would something along the lines of the 1800's pale ales.

Flavours of maturity in stored beers also extended based on my reading to diacetyl, produced mostly by action of lactic acid bacteria. This probably accounted for the nutty taste noted by some writers in aged beers.


mentaldental said...

Somehow brett. seems more suitable for dark beers. But, of course, Orval gives the lie to that idea. Is there any suggestion that Orval is descended in a direct line from English pale ales?

karel de vlaming said...

Very nice post.
I've been told that Guinness used to have a brett as well, up to around 1980. Any idea whether this is true, and, how they solved the difference in taste?

karel de vlaming said...

And as well, where did you find that book?
Love to purchase it myself.

Ron Pattinson said...

Karel, I'm not sure exactly when Guinness would have stopped having a brettanomyces character.

When they still aged FES in oak vats, it must have contained brettanomyces. I think it's a while since they blended vatted beer with Extra Stout. I'll have to look in a "A Bottle of Guinness Please".

I found the brettanomyces book on Abebooks:


Though there was only one copy and I got that.

Ron Pattinson said...

Mentaldental, when I once suggested a connection between Orval and Pale Ale, I was told I was an idiot. Looks like I might have been right all along.

Orval was developped at a time when British beer was popular in Belgium. And Orval does seem to have similarities with British export Pale Ales of the time: colour, dry-hopping, ABV. And now, of course, we can add brettanomyces to that list.

karel de vlaming said...

Thanks Ron, Guess I'll have to do with "Wild Yeast" and "Farmhouse ales" from the Brewers Association.
Further more, may i recommend this article? http://bierkoning.nl/2011/03/hout-hop-bier-met-brett/

karel de vlaming said...

It's probably not Orval having a direct connection to British Pale Ales, but Saisons in general (considering Orval a saison). Traditional saisons have a low ABV, a brett infection and where often dryhopped, when too many off taste appeared after the lagering. And I'm not even mentioning the use of Golding hops.

Anonymous said...

Very interesting. It's logical, since in the works of Hjelte Claussen, when he refers to brettanomyces, he call it "The English caracter". I think I was a key ingredient in the beer/ale industry of the time. But I wonder if many brewery used brett intentionaly as with the Colne Spring Ale. When it's there, and you work with wooden vessels... But.

Craig said...

Not to make assumtions, but wouldn't it be logical that any beer stored in wood, either cask, vat, or union, would have some Brett infection?

Does the connection of Brett to dark beers come from the fact that stouts have, historically, higher gravities than PAs, thus creating a more hospitable environment for the Brett to thirve in?

karel de vlaming said...

Hi Craig,
Just wondering, obviously brettanomyces needs it's sugars to live on, but why would a beer with a higher ABV be a better place for it?

Neil, Eating isn't Cheating said...

a very interesting and informative post. Thanks for your continued hard work, it's invaluable to my ongoing beer-based education!

Craig said...


I don't know! My thinking is that, I know Brett does better in partially fermented beer rather than used as a first pitch yeast. I'm maintaining the guess that beers that have a higher percentage of sugar, still in suspension, as they go into their respective wooden, holding vessles, would provide a better environment than of those that have fermented out.

Martyn Cornell said...

Karel - it also seems to be the case that Brett only comes into its own when standard Saccharomyces yeasts are no longer in a fit state to (out)compete with it, and that's more likely, I think, in a high-alcohol environment.

Ron, that's great stuff, and some of the comments so far bring up something I've been wondering about, how much British brewing influenced the Belgians, considering the popularity of several British beer styles in Belgium. There's a book for you!

Chad Y. said...

Brilliant find! That's Custers 1940's thesis.. I searched forever for that manual but not speaking dutch it wouldn't have done me a lot of good during my research on Brettanomyces yeasts...

Ron any chance you'll be translating more? That is seriously a gold mine! Shoot me an email if you can, I'd love to ask if a few specific things are in there as well as do a historical Brett pale..


Thomas Barnes said...

Extremely interesting and useful information. I'm just surprised that British brewers didn't go to single strain cultures earlier, given that Emil Hansen figured out the technique around 1890.

@Martyn. Brett and subsequent "waves" of microflora depend on dead, autolyzed yeast for some of their nutrients, although higher levels of alcohol (above ~6-8%) inhibit growth of slower growing critters like Lacto and Brett. For much more info, check out "Wild Brews" by Jeff Sparrow or do a search on "p-lambic."

Matt said...

I second Chad's call for more translations from this thesis. Especially anything that might shed more light on some brett strains deposited in yeast banks by Custers (and still used today)...

"CBS 74 Dekkera bruxellensis van der Walt. Near Ninove, Belgium (isolated by Custers, sediment in lambic beer, 1938) deposited by Custers in 1940 as b. bruxellensis"

"CBS 75 Type of of Brettanomyces lambicus Kufferath & van Laer. (isolated by Custers, sediment in lambic beer) deposited by Custers in 1940"

"CBS 77 Dekkera anomala M.T. Smith and van Grinsven. Type of Brettanomyces anomalus Custers. Isolated by Custers, Jan 1939, from stout beer, deposited by Custers 1940"

"CBS 78 Dekkera bruxellensis van der Walt. Type of Brettanomyces bruxellensis Kufferath var. non-membranifaciens Custers. received as Torula Brettanomyces Claussen;
Oct 1939 deposit"

"CBS 97 Dekkera bruxellensis van der Walt. Was Brettanomyces bruxellensis var. non-membranifacens. UK, Burton-on-Trent, stout beer, isolated by Custers 1939 deposited 1940"

"CBS 98 Dekkera bruxellensis van der Walt. Was Brettanomyces bruxellensis var. non-membranifacens. Netherlands, stout beer, isolated by Custers 1939 deposited 1946"

By the way, for some very informed reflections on why pure culture techniques with brett never caught on faster in England (and lots of other interesting things) read Dr. Brown's essay here:


Ron Pattinson said...

It looks like there's a fair amount of interest in more from Custers book. So I guess more will be coming. Just bear in mind that as I have to translate everything, it will take longer than an English text.

Ron Pattinson said...

Matt, which year and issue is that article in?

karel de vlaming said...

Are there still copyrights on that book? Perhaps it's possible to scan the whole thing. I'd like to help!

Ron Pattinson said...

Karel, I've already scanned the whole book. I assume that it's still copyrighted, being only 71 years old.

karel de vlaming said...

Is there a change of borrowing it?
Would be very pleased..

karel de vlaming said...

Found it!
But thanks anyway

Chad Y. said...

@ealusceop What is the spring Colne Ale that used Brettanomyces intentionally? I havn't heard of this before.

@Thomas Barnes Brett and other organisms do not depend on dead autolyzed yeast to survive and thrive. There must be some nutrients and sugars other then what is released from yeast cells. They can continue to sustain on them over time but is one of three parts of the matrix. Also Brett will live and thrive at between 12-15% abv.. if not higher depending on the strain.

@Matt I plan to go back and check some of those strains out.. problem is the CBS and NCYC charge an arm and a leg for a strain. Custers didn't look at the characteristics of Brettanomyces strains more he worked on the physiology and what led to later researchers terming the fermentation under anaerobic conditions which occurred faster in a species then under anaerobic "Custers Effect". Custer referred to it as Negative Pasteur Effect.

Jeff Renner said...

A bit of first hand experience here with Wyeast B. claussenii which I pitched into a finished 1.062 pale ale (Simonds Bitter from Old British Beers and How to Make Them). It scavenged plenty of non-fermentable (by Sacch.)sugars to become rather highly carbonated.

On the nose it has earthy pineapple tones, on the palate peppery root veggies (rutabaga), bitter celery seed, fenugreek, no particular acidity. Somewhat reminiscent of Orval but far less of the typical Brett. horse blanket.

All in all, interesting, but I prefer the cleaner bottles that I primed with sugar.

I also have some porter that I bottled with B. c. from WhiteLabs. It took more than a year to become pleasant, but that was as much from the weird brown malt as anything. Still, I preferred the non-Brett bottles. I have a few bottles left. I'll go down to the cellar (lucky us mid-western Americans - cellars are common) and open one of them.

Jeff Renner said...

Well, damn. The only bottles I have left of the porter are four w/o B. c.

Matt said...

Ron, it's actually a (1916) lecture, and not an article. The link is at the top of the page under “Reminiscences of Fifty Years’ Experience of the Application of Scientific Method to Brewing Practice”

Jeff Renner said...

Well, I need to withdraw my conclusions about the flavor of B.c. I opened a control bottle of the Simonds Bitter that was not inoculated with B.c. and was primed with sugar and it exhibited many of the same flavors as did the B.c. bottle, although less pronounced. It was not all that highly carbonated, so I am thinking that most if not all of the carbonation came from the primings, not from B.c., so it would seem that I have some kind of infection.

It's different from any I've had in nearly 40 years of brewing (I've had very few, actually), and is not typical of any I've tasted, so I'm stumped.

Unknown said...

Hi Ron. I've just come across your excellent post on the Custers book and was wondering if you have found the part in it where he discusses his isolation of Brett strains in wine (my area of expertise/interest). I'd be very interested to know which wine he tested and which strain he found. Thank you.

Unknown said...

I just tried Orval for the first time. As soon as I opened the cap I experienced a wierd flashback. I hadn't even put the bottle to my nose but there it was-the smell of English Bitter from 45 years ago, oak cask conditioned.

The bitter I remember was not very bretty at all maybe a touch but kind of tart, stale would be how I described it then.

So I am thinking I will experiment with some brett and see how it goes.

In the 50s some great English characterful beers, the 70s terrible decline, now a renaissance but a predominance of hop forward beers. Time to rediscover some roots?

Ron Pattinson said...


I always thought of Orval as an IPA. People used to laugh at me. But it turns out I was right.