My first "stuck" ferment

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Coodgee

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Short story...

First brew with the grainfather after 5 years break from brewing. previously have done 50+ AG brews.

Recipe was mainly BB ale malt with some wheat, flaked wheat and munich to 1046.

single step mash at 67 for 60 minutes.

aerated by holding the outlet pipe of the grainfather up high and dribbling the wort into the fermenter from a height. good foam on top.

pitched two packs of US05 onto the foam, a bit of clumping occurred because I was clumsy.

Fermented at 17-18 degrees - just in a room in my house but it is a fairly constant temp in there at the moment. I put my fridgemate probe straight into the top of the wort after sanitising it. it got as high as 19 degrees once and dropped to 16 once. Good Krausen and solid airlock activity after 14 hours. it was about the time it dropped to 16 that it stalled...

airlock activity stopped after about 3/4 days, i took a gravity reading out of curiosity and it was 1025. sealed it up nice and tight and airlock activity resumed.

it then blooped away for another days slow but steady and stopped today. that is exactly 7 days after I pitched the yeast. so today I thought it was done and added a dry hop addition. took a gravity and too my amazement it was still at 1024. only dropped one point!

so I gave it a swirl, currently sitting at 18 degrees. had a taste and it actually tasted fairly finished. not really sweet, if anything quite bitter, even a bit bitey, which might have just been the freshness/greenness. only hopped to 20 IBU. so since it tasted quite done I thought it might have been a dodgy sample, so I took another sample but it was the same.

the only other thing I did differently was added a tablespoon of ph 5.2 solution into the mash and 10g of calcium sulfate.

pretty weird. Think I will get a starter going with some more US05 tomorrow if I have time to get some from the LHBS. hopefully the swirl will get her going again.
 
Getting down to 16 deg hasn't helped with a speedy ferment.
Also 7 days isn't really a long time especially if it has been cold.

Give it a swirl and keep it warm and leave it for another week and see what happens.
 
I had similar problems with some recent brews (although my OGs were higher and I was pitching less, and not rehydrated yeast).

I'm going to start rehydrating and pumping pure oxygen in my wort from now on, but ...

This is only a suspicion - and maybe someone who's an expert in water chemistry could clarify - but my problems seemed to appear only after I'd started treating my water with CaCl and CaSO4.

Palmer's 'How to Brew' says this:


Magnesium plays a vital role in cellular metabolism and its function can be inhibited by a preponderance of calcium in the wort. Brewers adding calcium salts for water chemistry adjustment may want to include magnesium salts as part of the addition if they experience fermentation problems. …

If you experience stuck fermentations or low attenuation, and you have eliminated other variables such as: temperature, low pitching rate, poor aeration, poor FAN, age, etc., then lack of necessary minerals may be a significant factor.


My tap water (in Sydney from Potts Hill) is likely to be approx Ca of 14ppm and Mg of 5ppm.
EZ Water indicates a preferred range for Ca of 50-150ppm and Mg of 10-30ppm.
So my water additions started boosting Ca but not Mg. And I'd end up with, say, 100ppm Ca and Mg would remain at 5ppm.

Anyway, I've got some MgSO4 that I'll also use from now on. Just to be sure.
 
Coodgee said:
Short story...

First brew with the grainfather after 5 years break from brewing. previously have done 50+ AG brews.

Recipe was mainly BB ale malt with some wheat, flaked wheat and munich to 1046.

single step mash at 67 for 60 minutes.

aerated by holding the outlet pipe of the grainfather up high and dribbling the wort into the fermenter from a height. good foam on top.

pitched two packs of US05 onto the foam, a bit of clumping occurred because I was clumsy.

Fermented at 17-18 degrees - just in a room in my house but it is a fairly constant temp in there at the moment. I put my fridgemate probe straight into the top of the wort after sanitising it. it got as high as 19 degrees once and dropped to 16 once. Good Krausen and solid airlock activity after 14 hours. it was about the time it dropped to 16 that it stalled...

airlock activity stopped after about 3/4 days, i took a gravity reading out of curiosity and it was 1025. sealed it up nice and tight and airlock activity resumed.

it then blooped away for another days slow but steady and stopped today. that is exactly 7 days after I pitched the yeast. so today I thought it was done and added a dry hop addition. took a gravity and too my amazement it was still at 1024. only dropped one point!

so I gave it a swirl, currently sitting at 18 degrees. had a taste and it actually tasted fairly finished. not really sweet, if anything quite bitter, even a bit bitey, which might have just been the freshness/greenness. only hopped to 20 IBU. so since it tasted quite done I thought it might have been a dodgy sample, so I took another sample but it was the same.

the only other thing I did differently was added a tablespoon of ph 5.2 solution into the mash and 10g of calcium sulfate.

pretty weird. Think I will get a starter going with some more US05 tomorrow if I have time to get some from the LHBS. hopefully the swirl will get her going again.
Readings with a refractometer or a hydrometer?
 
pcmfisher said:
Getting down to 16 deg hasn't helped with a speedy ferment.
Also 7 days isn't really a long time especially if it has been cold.

Give it a swirl and keep it warm and leave it for another week and see what happens.
yeah that's what I was thinking, gave it a swirl last night. I might stick it in front of a heater for half an hour and get the temp up to about 20 and look for activity. I ended up making an 800ml starter with 2 packs of MJ M44 dry yeast that I had on hand last night. This morning it had a good krausen and was very bubbly. I am thinking of pitching that tonight after I warm it up. I'm thinking it will do the trick, but maybe overkill!

I would have just been patient if it had moved at all but it went 4 days only moving 1 point at most so that get's me thinking it needs something more drastic. It's more the shock of it happening for the first time. thought I was above this noob shit haha.

kaiserben said:
I had similar problems with some recent brews (although my OGs were higher and I was pitching less, and not rehydrated yeast).

I'm going to start rehydrating and pumping pure oxygen in my wort from now on, but ...

This is only a suspicion - and maybe someone who's an expert in water chemistry could clarify - but my problems seemed to appear only after I'd started treating my water with CaCl and CaSO4.

Palmer's 'How to Brew' says this:





My tap water (in Sydney from Potts Hill) is likely to be approx Ca of 14ppm and Mg of 5ppm.
EZ Water indicates a preferred range for Ca of 50-150ppm and Mg of 10-30ppm.
So my water additions started boosting Ca but not Mg. And I'd end up with, say, 100ppm Ca and Mg would remain at 5ppm.

Anyway, I've got some MgSO4 that I'll also use from now on. Just to be sure.
That is really interesting and a good point thank you. that is the first time I have used gypsum so it certainly correlates. I wonder if a late addition of some mgSO4 in boiled water would do the trick at this stage?

HBHB said:
Readings with a refractometer or a hydrometer?
refractometer. checked calibration.
 
Coodgee said:
refractometer. checked calibration.
Checked Calibration, cool, but have you allowed for Alcohol error?

Reason I ask is because with an OG of 1.046 and a FG reading of 1.024, then your real reading will be about 1.011.(ish)

In which case it isn't stuck, it's finished.

(sorry if this is suck eggs stuff for you)
 
HBHB said:
Checked Calibration, cool, but have you allowed for Alcohol error?

Reason I ask is because with an OG of 1.046 and a FG reading of 1.024, then your real reading will be about 1.011.(ish)

In which case it isn't stuck, it's finished.

(sorry if this is suck eggs stuff for you)
!!! Sweet mother of jebus!!! That is the answer! I had no idea there was an alcohol correction factor!! The ******* was done after 4 days!!!

First time I have used a refractometer!!

Thank you sir. You learn something new every brew day. :blush:
 
This is as common an issue as non bubbling airlocks.
I used to own a refrac but sold it. Do any come with a big warning to take alc into consideration when using?
 
manticle said:
This is as common an issue as non bubbling airlocks.
I used to own a refrac but sold it. Do any come with a big warning to take alc into consideration when using?
I know a lot of forum folk say the airlock is not an indicator of fermentation activity but surely it should be and in fact is. I like to be able to monitor the progress of my brews and the amount of CO2 being output is interesting and informative. I know in the end most brews will sort themselves out with a RDWHAHB philosophy and just leave it for 2 weeks but where is the fun in that?

And yes there should be a warning label for us new refractometer users. how would you know this otherwise??

I noticed my Helles that I put down on Saturday with a 2L starter of WY2112 has stopped activity as well after 5 days. That would be an exceptionally quick ferment at 14 degrees but I'm not going to stress this time! maybe it's the yeast nutrient and mash schedule of 55, 60, 70, 75. RDWHAHB , RDWHAHB , RDWHAHB ...
 
It's not a reliable sign - it can bubble when terminal gravity has been reached and it can show no signs when fermentation is indeed taking place.
 
yeah but it would a be brave brewer to see absolutely no airlock activity after say 3 days and just assume everything is fine and not check things out.
 
It would be a silly brewer to see no airlock activity for 3 days, see a huge krausen, and think it's not fermenting.
 

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