Besides the dregs from the Girardin Gueuze, I also had dregs from BFM’s “La Torpille” to have a look at. Since BFM is a rather small Swiss brewery, it is well known in the US for their legendary L’Abbaye de Saint Bon-Chien. I am very lucky to have full access to all of their brews and I am a big fan of their La Torpille. It is in my opinion quite unique for Switzerland because the beer culture here is quite similar to Germany. BFM stands out because they produce sour beers, beers with spices and so on. To summarize: they brew not according to the Reinheitsgebot…and thats quite rare here in Switzerland, another country where the fizzy yellow stuff dominates.
What I did with the dregs is the following: I had two times 5 liters of a Belgian style beer to do some funky stuff with. After the primary fermentation with Wyeast’s #3522 Belgian Ardennes and #3787 High Gravity Trappist I blended the two and racked it in a secondary fermenter and put two dregs from BFM’s La Torpille in there. The beer, after nearly three month after adding the dregs, is quite clear and has a little funky aroma and some cherry notes. No sourness so far. After taking a sample to see how it tastes, I took the opportunity to look at the bugs with my microscope. Lets have a look at the pictures from the dregs:
Since there are not a lot of pictures of Brettanomyces on the web, it is therefore quite difficult to determine what those bugs are. But looking at Jasons Sciencebrewer page, the cells from my last picture look like those in Jasons picture CB-2 (bottom). He concludes his cells to be wild yeasts, Brettanomyces to be exactly. In the comments below his post it is assumed that it could be Brettanomyces lambicus. I therefore assume that my wild yeasts are B. lambicus due to the morphological similarities. This seems to make sense to me as the Brettanomyces cells look like torpedos and the name of the beer, La Torpille (French), means “The torpedo”….
Beside the wild yeasts there were some Saccharomyces detectable (not shown). But I could not find any kind of bacteria.
The only thing I am interested is what the wild yeasts can contribute to the aroma and flavor of a beer. I therefore will compare this yeasts from the dregs against other known wild yeasts from Wyeast in the future. Since the wild yeasts are already in a beer, I already mentioned that the beer has a very nice cherry note. Since B. lambicus tends to produce cherry notes (see Wyeast description), I therefore assume that the wild yeasts in the dregs of La Torpille are of the specie Brettanomyces lambicus.
I will streak the bugs from the BFM La Torpille dregs on Sabouraud agar in the future to have a look at the morphology of the cells on the agar. Sabouraud is an agar used to cultivate yeasts and not specific for Brettanomyces or any other yeasts and I use it for Saccharomyces cultivations and purification purposes. I purchased some B. lambicus and B. bruxellensis from Wyeast and will streak them as well.