Kit brew weirdness. Yeast assassin?

[Prostheta]

Hi everyone - first post after being a long-time lurker, so apologies for my first words being ones that bring a problem to the table....

We set up a couple of buckets of extract mix a few weeks back; everything more or less by the book. Sanitisation, monitoring of OG through to FG and temps, priming and racking in 5l mini kegs for secondary.

The kits were a St. Peters IPA and a Woodforde Wherry. The primary ferments took about two weeks (the IPA finished first) rather than one, but hey. It takes what it takes I guess.

The IPA is textbook. I would praise a bar if I were served that. Perfect carbonation and an all-round belter. Zero issues with the 5l mini kegs either. Oddly, it's better than the commercial product from the bottle.

The Wherry however....isn't. We had an issue during the primary with the lids of both buckets cracking and no longer producing an adequate seal. Only as much as prevented the airlock bubbling, but not massive air exchange. It happened on both buckets so I don't see this as the culprit. The IPA had a far bigger crack in the lid.

The Wherry stuck out at 1022-24 for a while. Far too long. The top of the ferment dropped clear with a few small islands of bubbles persisting. Everything dropped out of solution, it seems. Rocking the baby didn't wake her up, so I stole the yeast from another kit we have and produced a starter to see what we could do. Pitching that produced little to no visible result, however after a week the gravity dropped to a steady 1014 for three days.

Racking this up into 5l kegs and priming each one with 20g of table sugar should have been golden. Exact same process as what succeeded with the IPA.

Broaching a keg tonight after two weeks produced a sweet and virtually flat disappointment. It might be that the other kegs are not the same as this one, however I doubt it.

Stuck ferments are what they are, however these were maintained at a more or less constant 20-21°C. I don't quite understand as to how the yeast could choose to drop out of solution so early (I pitched an additional 250g of dextrose in the initial brew) despite apparently ideal conditions and as to why a second pitch of yeast didn't take as vigorously as it should....

Apologies for the wall of text. It is quite apparent that there was alcohol in there, even if it did taste like arse.

 

[Prostheta]

I forgot to post that I am aware of the 1020 gravity issue with Wherry, however a lack of understanding as to exactly what this is (temp? yeast fractiousness?) and how to fix it wasn't immediately forthcoming. It seems odd that a second pitch of a different yeast (from a Yorkshire ale kit) didn't take, and that there wasn't enough active yeast present to precipitate a secondary ferment.

How could the yeast have just dropped out of solution? There was no immediate evidence of infection, and it certainly doesn't taste or smell "off"like you'd expect if there were. I feel we've either made a fundamental mistake or Wherry just isn't going to happen without a fight....

 

[Suicid]

I feel we've either made a fundamental mistake or Wherry just isn't going to happen without a fight....

Hi Prostheta,

Sorry to hear you have a problem with Wherry.
I did it several times, last 3 months ago, and drinking it right now. Excellent smooth bitter.
Last I kept at 22C, OG was 1.044, FG 1.011. Bottled after 2 weeks in primary. No problems with bottle carbonation.

So your 1.014 looks a bit hight but we could accept it as ok.

All my the Wherries came out simple, without any extra dancing at my side. So I don't think it is a kit problem in general.

How old your Wherry kit was? I could imagine it is something wrong with the yeast (perhaps in both kits wherry and yorkshire), but the last I made was almost expired (got it from sale bin).

 

[Prostheta]

That's a possibility I can neither confirm nor deny. I'll certainly check dates in future. Neither of the kits were on offer though, so it's difficult to tell if this was the issue.

The IPA was (and is) a belter so that's going to be a regular fallback I think. Beyond this I think we'll be trying out a few recipes using spraymalts, additional ingredients and Wyeast packs. It's sort of a knock to the confidence when a "simple" kit falls short of expectation despite everything having been done down the the last letter. Reviews of the Wherry are in line with your experience, which is why we chose it. Shame we never came across the 1020 issue otherwise we'd have done our homework on what causes it (we still haven't figured that one out yet) or simply moved to a different kit.

Yeah, we were told that 1014 is about the target however stable FG is stable FG. Some people report getting it even lower than yourself, however the values I've seen seem a little excessive.

Not entirely sure what to do with this lot now. I suppose it might be a bit far gone to consider dumping the remains of the last four kegs (about 18-20l worth) back into a sanitised tub and attempting to start up a fresh ferment? It seems like it might be a waste of yeast given how the previous repitch failed miserably.

 

[Suicid]

I suppose it might be a bit far gone to consider dumping the remains of the last four kegs (about 18-20l worth) back into a sanitised tub and attempting to start up a fresh ferment? It seems like it might be a waste of yeast given how the previous repitch failed miserably.

Yep, might be so. I've never tried such trick myself. The most advanced rescue I did once was repitching yeast into bottled beer because of lack of carbonation.

I read somewhere people pitch the champagne yeast like lalvin-1118 to push from 1020. 1118 is a very aggressive and will ferment beer almost dry. But I'm not sure you'll finally get a Wherry from this experiment.

 

[brewcat]

How long was too long on your FG? Then 2nd question. What was your OG? Then, two weeks isn't really that long to carb. What temp are you carbing at? Give it two more weeks.

 

[Prostheta]

OG was 1044 and FG 1014 over three days of monitoring. It went down about 1-2 points per day after repitching. Given that this was from 1020 it seemed odd as it stood. This was primary, and it sat in for a few days over two weeks. Even uncarbed it's too sweet - far sweeter than it should be. It raises few conflicts. Was there too much unfermented product left in the primary despite sitting at 1014 for three days, and if so why didn't the yeast pick up on that? How/why did the brew seem to prefer clarifying, dropping the yeast out of solution instead of fermenting?

It seems a little contradictory to established knowledge. I'm not saying this is unique, simply strange. Everything sat at a more or less constant 19-21°C ambient. I presume the temps internally were higher, however it wasn't exactly a hostile environment for this simple brew. I can understand the dating issue. My wife confirmed that the Wherry was a month before expiry. Can't have helped.

The lack of carbonation seems to imply that there was nothing to work on the priming sugar in the kegs. The apparent drop of all yeasts in the primary seems to correlate. That doesn't seem normal at best.

 

[brewcat]

Sounding like underpitched yeast. Still think you should give it a couple weeks.

 

[Fedora]

If I understand, you are keg conditioning. Corny keg?

My money is on the lid not sealing. It won't carb if it's not sealed. Did you seat the lid with CO2 before conditioning?

 

[Prostheta]

5l minis for the moment. I do have plans to refurb a refrigerator into a kegerator, however until then we are running small. Probably for the best since I think we need to hammer out issues like this before we go tying up an entire corny. The mini kegs were adequately sealed; the rubber bungs were greased with a little petroleum jelly also.

Underpitching sounds likely too. After all, kits are never generous. The second pitch when it stuck at 1020 was a slow starter but it crawled through to the FG eventually. I think we're going to stick with the St. Peters IPA in future. That's a doozy which we're happy to rack keg after keg on. Zero issues start to finish. We'll experiment and learn from second bucket. We're thinking a basic Belgian blonde style beer from extract and pitching Wyeast or similar.

This is more or less where the thread goes off-topic, however if underpitching is a likely candidate for the problem (it doesn't seem to explain the lack of carbing though) then might we see the same issue with 20-23l (5-1/4 to 6 gallons) with one packet of Wyeast pitched? The smack packs are recommended for 5 gallons (19l) which is a little shy of four kegs.

My point being, I'm unsure as to whether mild underpitching has a distinct point at which it causes problems or whether it is a gradual dropoff. Maybe I should just get over losing those two additional glasses, or perhaps that could be construed as heresy....