Eureka, another post about dregs and a really awesome beer. Since September 2011, Bern has a new local beer pub for beer geeks like me. The bar is run by the legendary Erzbierschof and he has a huge variety of different beers in stock. I have to mention that there was no beer-geek-pub in Switzerland before.
My first visit was in mid September and had a bunch of beers like Anchor Steam’s Porter, Southern Tier’s Pumpking and a 3 Fonteinen Oude Gueuze. I have to say, I was quite speechless after the first sip of this particular Gueuze and had a big smile in my face (like the Cheshire Cat…) This beer is still one of my favorites.
I got myself another bottle in December and tried it on the 14th of January 2012. Still the same awesome beer.
Aroma: Could notice some hints of apple, slight vinegar note, horse placket, very funky. I just love the smell.
Appearance: Yellow, lightly hazy, some carbonation visible, light white head.
Flavor: There are a lot of different flavors. I can pick up apple notes and maybe some apricots? The beer is pretty dry and lightly acidic.
Mouthfeel: light body, medium carbonation, pretty dry finish.
Overall Impression: Well, another awesome beer. Very nice aroma. And there are a lot of different flavors on the palate. Just a bit acidic and pretty dry finish. I guess this could be a good beer to get into sour beers as the sourness is not too overpowering in my opinion. Would I drink another one? Definitely! Get yourself a bottle if you can.
And since there were some dregs in the bottle, I just dumped them in a starter…
01/15/2012: The cultivation begins. Dumped the dregs into a sterile 100 mL starter (10°P) made with dried malt extract and some yeast nutrients.
01/28/2012: There is a sediment in the bottle. The starter has a very strong acidic aroma, smells like vinegar but in a good way. The liquid was quite sticky and thick. This might be what brewers call ropy or sick. Pediococcus produces a carbohydrate compound that leads to an elastic consistency. The consistency should get back normal in a few months [Cilurzo, p10]. I guess this could prove the existence of Pediococcus in the dregs?
01/30/2012: Plated the bugs from the sediment on some agar plates.
02/02/2012: Could observe just one kind of colony morphology on the Sabouraud agar plates. And it turned out to be a kind of bacteria, not yeasts. It might have been Acetobacter.
02/15/2012: Further colonies are visible on the agar plate. Some colonies are very small (< 1 mm diameter) and some look very similar to yeast colonies (white and round).
I took a white colony from the plate (from the destroyed colony in the right part of the picture) and looked at the bugs with my microscope. It looked as following:
First of all, I have to apologize because I still do not know the exact magnification of the picture as my camera uses a different kind of magnification. I normally look at the cells with a 800x magnification and take a picture. But the magnification in the picture is lower than 800x. I am still working on a solution to get the exact magnification.
Lets get back to the picture. The cells are again a kind of yeast due to their size. But they look very different to normal Saccharomyces cerevisiae. S. cerevisiae are oval shaped cells in general. But here we have some kind of elongated cells. And I have no idea again what I got myself here… It could be a kind of Brettanomyces or other yeasts I guess. One fact that points to Brettanomyces is the time it took the microorganisms to form colonies. Brettanomyces is known to be a slow grower.
I learned from this experiment that it is possible to harvest some bugs from dregs of a sour beer. I have a very strong feeling that the bugs I have here are a kind of Brettanomyces. If that would be true, then using Sabouraud agar and some patience is good enough to get some Brettanomyces out of dregs.
Now I wait until the small colonies (the very small ones with a diameter < 1 mm) form bigger colonies and do another microscopy analysis.
As already mentioned in the last post in the pentade about agar plates, I will publish a summary post about the experiments and include some new results as well (like the ones above). But please be patient, my time is very limited at the moment. Anyway, I will try to publish at least one post a week in the future. Stay tuned!
It kind of looks like Kloeckera apiculata (see http://investigadores.uncoma.edu.ar/labmicrobiologia_biotecnologia/imagenes/K%20apiculata.jpg and http://investigadores.uncoma.edu.ar/labmicrobiologia_biotecnologia/imagenes/Kloeckera.jpg for some examples) which are said to be present in early stages of lambic and spontaneous wine fermentation, but that would probably indicate that they are fast growers. I’m also not sure whether k. apiculata forms long chains like I see in your picture.
Would a smell test be useful for brett, or do the characteristic compounds not form with this sort of growth?
Thanks for your pictures. I already thought about Kloeckera as well and came to the same conclusion as you did 🙂 But the cells could be Kloeckera nevertheless.
I did not found an easy way to prove the existence of Brett without a fancy lab equipment yet. And maybe a smell test could be easy way to do so. I planned on dumping the different cells in starters and do a sensory evaluation. But I read about all-Brett brews where the characteristics of the Bretts was very subtle… This would support your expectation about the lack of specific Brett compounds. Do you have any experience with All-Brett brews or starters with Bretts?
No experience yet, unfortunately.
However, I vaguely remember reading a blog article with something about pitching rate for all-Brett beers. This is strictly conjecture, but Brett in secondary is pitched into rather poor conditions, whereas an all-Brett beer would get a larger pitch. Maybe that healthier pitching rate also means less of the characteristic compounds and more straightforward fermentation?
That might be an interesting experiment on its own. I was planning on streaking the culture I’ve been keeping from Girardin Gueuze, which even after two feedings and an almost complete discard (i.e. I used only the very bottom of the dregs) retains a lot of the character. Hopefully I can isolate some strain of Brett out of that.
I am planning on doing an all-Brett brew soon and I read about the higher pitching rate too. A higher pitching rate could indeed lower the characteristics of yeasts: In wheat beer brewing, breweries in Germany tend to underpitch for increasing the flavors and aromas of the wheat yeast strains… I guess this is directly applicable for Brettanomyces. Vinnie Cilurzo mentions in a presentation (link is in the post) that a high amount of oxygen could help to decrease the character of Brett as well. And there is a lot of oxygen in my starters at the beginning. I should think about a method to get the oxygen out of the starter. Maybe flood the starter bottle with CO2?
I am still incubating an agar plate with the bugs from the Girardin Gueuze to get some Brettanomyces out of there myself. Please let me know if you have any success doing so.