W34/70 stuck fermentation?

[alsch890]

Hi there,

I don't know if I am playing tricks on myself or worrying over nothing. I brewed my annual Czech pilsner last Saturday and pitched 2 packets of W34/70 into 14-15 litres as usual, pitched at 14 degrees. I stuck it on the heat pad set to 13 degrees wrapped in an old sleeping bag as usual. The next morning it was already bubbling like crazy which is pretty quick for this yeast in my experience. However after about 4 days it seemed to have stopped. I had a peek and could see a really nice krausen on top. I had a look again today (7 days) and the krausen is still there but not further activity and the liquid in the airlock is "level" i.e. there is not pressure on it.

Anyone think this could be stuck? I did give the bucket a light shake today just in case. I'm not sure whether I am tricking myself since after probably 50 odd brews (including several using lager yeasts) I don't tend to open the FV and have a peep, I just leave it for two weeks and then rack it. I am reluctant to draw a sample since last time I did that the tap on the FV ended up getting mouldy between then and racking day and infected the beer (one of my two failed brews!) but I suppose I could break through the krausen and take a sample off the top?

Any ideas most welcome, or I just leave it alone and wait....

Cheers!

 

[NotSure]

I used W34/70 a few months back to make a Pilsner and then used the yeast cake for a Baltic Porter. My experience with W34/70 was similar to what you're describing - not sure when the krausen dropped though. I did gently rouse each after it looked like it quit and got a slight bit more of activity. The Pilsner gravity was 1.012 and the Baltic Porter was 1.023, both stable and the batches turned-out very well. The Pilser is long gone, but the majority of the Baltic Porter is aging and carbonation levels are stable at last check.

I'd check the gravity as usual, and if you do it from the tap, clean/sanitise the best you can (I usually spray a bit of star san). If the gravity is stable and where it should be, I'd say you're good to package.

 

[alsch890]

Cool, thanks for the reply. I prefer W34/70 to S-23 and S-189 but hadn't noticed this before. then again maybe I didn't look for it! I'll keep an eye, give it another couple of shakes and take a reading before racking. If I have to leave it another week then so be it.

 

[dave_77]

Just checked a recent fermentation that I did with this yeast and it looks similar profile..I started at a lower temp so activity was a little slower but once it started it dropped to final gravity in 4-5 days as you can see from ispindel data below

 

[UKSkydiver]

Similar curve here. 34/70 although fermented at 17'c
All done in 3-4 days (but left alone for the requisite 2 weeks)

You need an ispindel, at least that takes away some of the guess work.

 

[MrRook]

You need to take a gravity reading. What was your original gravity?

 

[dave_77]

Similar curve here. 34/70 although fermented at 17'c
All done in 3-4 days (but left alone for the requisite 2 weeks)

You need an ispindel, at least that takes away some of the guess work.

View attachment 62898

Agreed..even if the numbers aren't always 100% accurate no fermentation anxiety

 

[Hanglow]

My last lager done with it took a touch over 2 weeks, that was all at 12c though. Bit slow for my liking at that temp

 

[alsch890]

Similar curve here. 34/70 although fermented at 17'c
All done in 3-4 days (but left alone for the requisite 2 weeks)

You need an ispindel, at least that takes away some of the guess work.

View attachment 62898

I was thinking exactly the same when I saw the pretty graphs from brewfather! will definitely look into one. I never heard of it before.

 

[alsch890]

You need to take a gravity reading. What was your original gravity?

Yes, I think you are right. The reason I posted is I was trying to avoid taking a reading prematurely so just wanted to check first whether people had observed similar with this yeast. Its about the 4th or 5th brew Ive done with it and hadn't noticed before. I'll give it a couple of days to see if it changes and then take a reading I think.

 

[alsch890]

Just to update this thread. I racked this tonight after 14 days. There was still a lot of krausen floating about on top but FG was 1.014. A little higher than I expected (aiming for 1.010) but I wonder if my TLC had the opposite effect. I got a fair bit of yeast coming through the bottling stick too. So my lesson is, don't fudge about. Tasted pretty good from the sampling tube though.

I've always preferred W34/70 for clean pilsners, using S-23 or S-189 on other stuff like Viennese, smoked or black lagers but this year I've brewed a pilsner with S-189 and now this one with W34/70 and I have some S-23 in the fridge so might be a good time to compare.

 

[MrRook]

Just to update this thread. I racked this tonight after 14 days. There was still a lot of krausen floating about on top but FG was 1.014. A little higher than I expected (aiming for 1.010) but I wonder if my TLC had the opposite effect. I got a fair bit of yeast coming through the bottling stick too. So my lesson is, don't fudge about. Tasted pretty good from the sampling tube though.

I've always preferred W34/70 for clean pilsners, using S-23 or S-189 on other stuff like Viennese, smoked or black lagers but this year I've brewed a pilsner with S-189 and now this one with W34/70 and I have some S-23 in the fridge so might be a good time to compare.

I'm doing a pilsner on Sunday with S-189.

 

[IceQueen]

View attachment 62890View attachment 62891

Hi Dave,

What is the green curve?
What are you using to do that fency stuff?


LG Maddy

 

[UKSkydiver]

Green is battery voltage:

The charts is a feature of Brewfather. This is a brewing app. Loads of info about that.

The data for the chart comes from an iSpindel. This is a floating hydrometer that sits in the wort whilst it is fermenting and sends info to Brewfather as to the angle it is sitting at. From this angle you can (roughly) work out the gravity.

 

[IceQueen]

battery? why is that status imprtant?
Could have been the capacitancefrom the values.

 

[dave_77]

battery? why is that status imprtant?
Could have been the capacitancefrom the values.

See if it's time to charge before your next brew or just clean and go again..