Tag Archives: dcy02

DCY02 & 03 Test Tasting

DCY02 and DCY03 Test BeersI have been sampling the beer I brewed in April periodically since I bottled in April. With two bottles left of each, it seemed like a good time to write an actual review.

This beer started as a 1.040 pilsner extract wort, hopped lightly with Hallertau only at 60 minutes. Both finished at 1.004, an apparent attenuation of 90%. Consequently, both are a bit thin in the flavor department. But beyond that, they differ quite markedly. The results were quite a surprise.

DCY02

  • Appearance: Very clear, with a pale gold color. The bottle released a lot of CO2 after uncapping. Pouring slowly straight down the middle, it developed a thick, foamy head that dissipated fairly quickly.
  • Smell: Classic Brett funk and phenolic smell. Very lambic-like. A faint background note of fruit, especially strong while pouring. I believe this is the “cherry pie” many have described from Brett beers.
  • Taste: Quite tart. Not a sour beer by any means, but it is noticeably acidic, especially compared side-by-side with the DCY03 beer. Taste is straightforwardly Bretty, hard to find much unique beyond that.
  • Mouthfeel: Surprisingly full, given the high attenuation and low OG. Prickly carbonation.
  • Overall: Not a great beer by any means, but definitely enjoyable. This could be a great yeast for lambic fermentations for sure, and with a more interesting wort could be a good sole fermenter.

DCY03

  • Appearance: Same as DCY02, perhaps a bit hazier for some reason. That is probably sediment from the bottle, not suspended yeast. Poured with large bubbles at first, but eventually developed a thin head.
  • Smell: A bit stronger phenolic note, almost Band-aid-like. Minimal funk, though that may be the other smell masking it.
  • Taste: Bland. Slightly spicy, with a bit of peach in there somewhere. A little tartness, but nothing compared to DCY02’s.
  • Mouthfeel: Quite thin. Due to the sluggish refermentation this may be due to different levels of carbonation compared with the DCY02 beer. The difference is very evident.
  • Overall: A major disappointment, given how nice this yeast smelled in the starter. None of the fruit notes from that stage are present, and the stronger Band-aid note is distracting. It struggled as a refermenter, apparently, as carbonation never fully developed even after months in the bottle. It could be useful as a secondary fermenter (though not as a bottle conditioning yeast) or in conjunction with another Brett strain for primary. I would definitely use a bottling yeast if using DCY03 solo.

I still have one more bottle of each that I will revisit in a few months. Until then, this gives a pretty good indication of what each yeast does.

DCY02 & DCY03: DCambic Isolates

DCY02 and 03 Fermentation in Progress

I am happy to report that isolating the yeasts from The Mad Fermentationist’s DCambic was a success. I have written about it previously and had some issues at first. A lot of stuff going on in life then kept me from the project for a few months but eventually I got the time to get it going again. I have been posting off and on about it on Twitter, but it’s time I document it here.

The key to success the second time was growing a liquid culture first from a sample Mike gave me, rather than plating it straight from the sample. After a few step-up culture iterations I was able to isolate four different yeasts from the beer, instead of just the one I got the first plating attempt. Two were useless for brewing: one is possibly Rhodotorula and the other is another yeast that does not ferment. The others were almost certainly Brettanomyces.

I can tell them apart on a plate because one (DCY02) grows white colonies and the other (03) tan colonies. Liquid cultures are also markedly different: DCY02 forms a pellicle very quickly, smells very funky and drops out fairly quickly, whereas DCY03 takes much longer to form a thinner pellicle, smells very fruity and drops out a lot slower. Taste profiles from the starter are along the same lines as the smell.

I made two simple extract beers in April (1.040 of pilsner DME) and the picture above is of fermentation about two weeks in. They were slow to start but that may be due to low pitching rates. In any case, I have not yet bottled these as they seemed to reactivate after I moved in late May. Perhaps just shaking them a bit roused enough yeast into suspension to do something, and I want to make sure they’re done before I bottle. (I will update this once they are done.)

Strain Descriptions

DCY02: The “white” isolate, based on colony appearance. This has a funkier Brett character with less of the fruity qualities. It produces a pellicle very quickly, and during fermentation produces a thick foam cap that looks more like Sherry flor than ale yeast kräusen. It dropped out of suspension faster than DCY03.

DCY03: The “tan” isolate. This is significantly less funky, and a lot fruitier. It doesn’t produce much foaming during fermentation, and in fact may appear to be doing nothing at all. If shaken, though, there will be a lot of CO2 released. It did not produce a pellicle until several months after pitching and left the wort cloudy for about a month.

Distribution

I hope to have more details soon, both from my beers but also from those of a few brewers I sent samples to. This was also the first time I’ve distributed anything so I kept it limited to four people. However, in the future I will release larger amounts to whomever wants it for a small fee to cover shipping and materials. Future announcements will be made on the blog and on Twitter.

Update

I was hoping to premiere DCY01 to interested parties at the January DC Homebrewers’ meeting. Since it’s this Wednesday, and I haven’t started culturing it yet, that’s not going to happen.

Every once in a while I realize that this is much more difficult than it looks, and I have the results to prove it. It starts to feel like I’m in way over my head as a total amateur. My past two efforts at growing the cultures have resulted in sour starters. I’m not quite sure at what point the contamination is setting in so it’s difficult to know what to change at this point. The plates and slants are clean, as far as I can tell, but they seem turn sour in the second step up. It turns cloudy with a less cloudy layer on top of the liquid. So far that looks like a telltale sign of infection.

One possibility that comes to mind is the fact that my building’s heat is quite intense right now and the radiator in the kitchen leaks a bit. The air is humid and probably teeming with  bacteria. It doesn’t take much to contaminate a tiny sample of wort with an initially tiny population of yeast. I’m not sure how much the flow from the single alcohol burner’s flame helps avoid things from falling in. It’s worth trying to do it in another space.

There are other possibilities I’m less likely to be able to work around. I remember reading somewhere (a forum post) that yeast colonies on plates are often contaminated with bacteria. I haven’t been able to find anything more on this in my limited research. It seems a bit surprising due to the idea that an isolated colony on a plate is supposed to be descended from a single cell, and on my plates there are no visible bacteria colonies. But this would support the claim I’ve seen in some places that plating is not effective at isolating yeast from bacteria without some sort of antibiotic media (out of my reach as an amateur, as far as I can tell). It doesn’t help that I don’t have access to a microscope to test this out or help identify the source of my problem.

In spite of all of this, I am working on what will hopefully be DCY02. One of the two step-up cultures I just talked about is this one, so I had to restart the process. Hopefully by next week, when I will be off work, it’ll be ready to go so I can brew a one-gallon batch with it.

Perhaps I should attempt more straightforward yeast ranching using known-good cultures. I have a slant of WLP001 I cultured out of the remnants of a tube. I should try stepping that up to a starter since it is more likely to be clean than my wild cultures.

Update: I have now seen this with cultures that were not infected with bacteria–at least not noticeably–so it is probably not a telltale sign of infection after all. In the most recent case it is just yeast that refuses to settle, even after refrigeration. It’s worth noting, though, that according to this document Pediococcus form a clear layer on top when cultured in liquid.