What the…? Did I accidentially brew a hefe? Did someone slip me a WLP300 disguised as an 029?!!
Just racked my first Kolsch to the keg for a couple-week rest at 32 F and tasted the sample. Been crashing it at 32 F for a few days since confirming fermentation was complete to be sure all that could drop did drop. Very different than what I tasted BEFORE fermentation. Of course some change is to be expected, but I certainly did NOT expect bananas coming out of a Kolsch! A hefe, yes; but not a Kolsch.
But of course this IS my first Kolsch and my first experience with WLP029, and I haven’t really set too many expectations, but nobody told me it might smell like bananas! Has anyone else got bananas from their 029 fermentations?
I pitched at and held a solid 60 F for the first few days until it slowed significantly, then slowly raised to 66 F over a few days, then crashed after a couple of day’s readings showed a steady SG at 1.007.
I have brewed my last 3 batches using WLP029 and have never got any banana whatsoever. I run it warmer; around 65 then cold crash without any issue.
Someone more knowledgeable will have to chime in here but the only thing I can think of is super high fermentation or infection. It sounds like temp was not a problem…
Can’t imagine it’s an infection - never had it happen, not to say it couldn’t happen to me, but I’m quite anal about sanitation (part of what I do for a living is certification of commercial food equipment (among other products) and sanitation is one of my strongest suits) - clean-rinse-sanitize is a regular part of each step in the process. Scratching my head.
Maybe it’ll clear up after a week or so in the keg… we’ll see.
Is there anything else that could give one an impression of banana? I can’t imagine fruity esters at 60 F for the fermentation, but again, I know nothing about this yeast except it attenuates well and drops like a two-ton heavy thing. The grain bill was 10 Lbs Pilsner, 10 oz Vienna, and 24.5 IBUs of Tettnang at 60-min. 90-min boil, fast chill, etc. Pretty simple brew, really.
Yes sir. 1.3L on a stirplate (5 gallon batch size, 1.048 OG, 86% viability according to YeastCalc), crashed when done, decanted most of the spent wort before bringing it back up to pitching temp (60 F) on brew day - my usual routine. Controlled fermeezer, checked everyday. Yeast smelled good when making the starter, smelled normal come pitch time as well. Pure O2 at 1L/min for 1 minute through a 0.5 micron stone just before pitching.
Say, that brings up an interesting question; does the temperature of your starter (while it’s fermenting) have an effect on ester production, and can those esters carry over during the pitch even if most of the spent wort is decanted? I ferment all of my starters at 72 F on a stirplate in an environmentally controlled lab, and get very consistent results thus far (been at it for two years now).
No, temp of starter should not be an issue. Sounds like you did everything right. Maybe use a fridge fermi meter to see that your fermentation chamber is what it is supposed to be. The only other things I can think of is you may have gotten a wild yeast, however unlikely that may seem or the vial was somehow mislabeled.
No, that is not normal at all. That yeast in notoriously hard to drop without finings or filtering. The beer in my avatar was made with 029 and fined with gelatin and lagered for 1-2 weeks at close to freezing.
I’ll be sure to ask the guys at my LHBS (and White Labs) about the possibility of a mislabeled vial - quality control is not always 100%.
Could I be misinterpreting this “slight banana” aroma as the sulfur associated with 029? Doesn’t explain the fast fermentation and floc, I know, but I gotta know what went down here - the engineer in me won’t let this go without a solid explanation.
Fast fermentation, banana and maybe even fast yeast crashing (assuming your beer is truly crystal clear) are all signs of warm fermentation temps. I’m assuming the “pitched and held at 60” means the actual temp of the fermenting beer. In which case I’d calibrate the fermentation chamber and make sure you weren’t fermenting warmer than that. I’m guessing you aren’t talking about ambient temp, but just to cover all bases, you probably know to account for exothermic activity, which could account for the banana/fast ferment. Maybe even the fast crashing, though I doubt the last part.
That said, I have fermented this strain as warm as 68 and it is a little more funky at those temps. Can’t recall if it was banana or what, just recall it was funky. It’s been 15 years or more since.
I personally don’t recall ever getting sulphur from this strain and I’ve fermented it pretty cold. Colder that 60. And I personally wouldn’t get confused between sulphur and banana esters. But that’s just me.
Just sent an email to White Labs - we’ll see what they say.
I calibrate all of my instrumentation against NIST traceable references at regular intervals, and you’re right; what I saw is indicative of a warmer-than-expected fermentation, but the instruments aren’t lying, far as I can tell. I’ll have a look-see tonight when I get home - the keg is sitting in there now, lagering. says it’s at 32, we’ll see.
Yeah, I know the center of mass in my fermenter can go 6 to 8 F higher than the outside of the glass carboy (where I take my readings) during an active fermentation, and I’ve always been a fan of cooler fermentations to keep things on the “clean” side, even if it takes a little longer. I also insulate the thermocouple so it is influenced only by the glass and not the ambient air in the fermeezer. So far I’ve not have any issues with fermentation, always comes out clean. This one’s weird, though.
I am cold crashing my first Kolsch right now as well. The sample I pulled to verify completion of fermentation smelled of bananas to me as well. Just very slightly. Could that be a misinterpretation? It went from 1.047 to 1.010 in 8 days. I kept it at 62F for the first 4 days until it looked to have slowed down, and then I bumped it up to 65F for the last 4 days. I did get a squirt of yeast in the tube when I pulled the sample off the bottom of the Brew Bucket. It settled out out nicely after a few hours and it pretty clear. I’m going to filter it this weekend and see how she goes.
Does it have the white grape character? To me that is the most distinctive part of 029, and my favorite part (if subdued). Without that I would immediately suspect a mislabeling of the vial, especially if it truly dropped clear that fast.
I use WLP029 for my Kolsch and have used it a dozen times or more without ever getting banana. That’s very strange. I too would contact White Labs for further discussion.
Ok, the take form the folks at While Labs essentially is that because I pitched at such a low temperature and held it there through fermentation until clean-up time, this condition may have stressed the yeast sufficiently to cause the production of Isomyl Acetate, which is the banana aroma I’m getting. Still doesn’t explain why it dropped in 4 days, but there it is.
Next time maybe I’ll pitch at 62 F, and once active, I’ll drop it slowly to 60-ish and let it rip until done, then raise back up to finish out.
I pitch this yeast at 56-58 all the time, hold for a couple days then ramp up to 64 for a couple days then finish out at 66-68. That is what gives me the best white grape/pear aroma, which is why I really like this strain.