Persistently STUCK fermentations

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gryphonkd

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Hi Brewers,

I am having a hell of a time getting my brews to ferment out lately.

I had started using liquid Wyeast recently and haven't had much luck so far.
Firstly I tried a lager, Wyeast Munich Lager II (2352), but never proofed the yeast or did a starter.
It went nowhere, literally moved a couple of gravity points only. I figured the liquid yeast must have been DOA; Had to repitch dry yeast to get it going.

Then I tried a farmhouse; Wyeast 3724 - Belgian Saison, again no starter.
Starting with OG of 1054 - and got stuck at 1030, left for 20days! Again had to repitch dry yeast to get it going; finished at 1011, so the sugars were fermentable.

After some research, I thought for my next two batches I would, firstly, airate the wort thoroughly with a beer stone, and secondly, would make a yeast starter.

My most recent brown ale, with Wyeast 1469PC - West Yorkshire Ale, I made a good healthy starter which was going furiously after 24hrs, then I added to the fully airated wort. (8hours running the beer stone)
A good OG of 1055, it took off fermenting beautifully for the first few days, and then slowed down.
It has now been 14 days, and it looks to be stuck again at 1030!

By this stage I had had enough of liquid yeasts and made another batch using a dry yeast from CraftBrewer American Ale
So an APA, fully airated wort, nice heavy OG at 1068. It started fermenting staight away, looking good.
And to my amazement is now stuck 14 days later at 1040!!

What the hell is going on?? this stuck fermentation problem seems to be independant of yeast, malt, gravity.
I am fermenting in a dark, (fairly steady temp) room at 21deg +/- 3 degs. Pitching at 21deg.

So again, I am going to have to throw more dry yeast at these batches to get them to finish.

I never used to have these problems at all - anyone have any idea what could be causing this?
My only idea is that my steriliser is too strong? or not rising out of the fermenters between cleans. could this be killing/impairing the yeast?
Surely not if I am observing such healthy starts to the fermentation with heaps of (Krausen?) within 12hrs of pitching.

Anyone else experienced this? Its driving me crazy.
Note: I have verified all these OG and SG values with both Hydrometer and Refractometer. All brews are full all grain mash.
 
How accurate is you mash thermometer? My stick thermo that I'd used for 4 years "never needs calibrating" was reading six degrees off. A mash done at 70 degrees can quite easily attenuate at 1022 for example. Your hydrometer OG reading is no guide in this case as it doesn't measure what sugars are present, just how much.

This wouldn't completely account for the high FGs you quote however. What you could try doing in addition is to thrash and aerate a brew after 24 hours. Even though you may have well aerated the wort, most of this oxygen is taken up during the "lag" period and an additional dose of 02 can result in a bigger yeast population. Especially with the UK yeasts and definitely for 1469 "stone square" style yeasts.

Edit: and try a spoonful of yeast nutrient towards the end of the boil. The brown stuff, not the DAP.
 
I reckon you should call someone else over to pitch the yeast in for you.
Definately some kind of yeast poltergeist operating through your being....


On a more serious note, try pitching some Nottingham Yeast. If that doesn't finish, there is something wrong with your wort / hydrometer.

It seems like the yeast are not getting something they need. Maybe try some yeast nutrient in the next batch?

What ingredients are you using? Process? Is there something common between all batches that may be causing the issue?


Cheers,
D80
 
First do a forced ferment on your wort it will tell you if its the wort composition causing problems, and yes check the hydro and temp reading device some are out a few points.
Dont try and do everything at once else you will not find the cause.
Nev
 
^ what he said.

Btw, Belgian saison is not a good yardstick to measure stalled ferments by. Can take a month!
 
Thanks for the replies all.
I'm pretty confident of the accuracy of the thermometer; using a very accurate digital meter and probe.
My mash process is pretty standard; 68deg - held very constant for an hour in insulated tun.
The only thing in common would be the cleaning process, mash process and the water; I'm having the same problem in different fermentors.
I'll try some yeast nutrient in the next batch in case the water is strangely defficient. Although, its just standard Melbourne water, which i've had complete ferments with before.

It will also be interesting to see if repitching some dry yeast into these stuck batches ferments them out was the case before on the Saison batch.
Nev - interesting article on the forced ferment; i'll also try that on the next batch to try and work out which side of the process the problem lies with.
 
I would say its a wort problem too be it cleaner/sanitiser etc, even if your water is deficient in some trace elements there should be enough to get a descent attenuation.
I cant see all your yeast being bad. One thing that does puzzle is you say some started well, this would not indicate a sanitiser problem.
Stick with the wort investigation for now before looking at other possibilities.
Nev
 
check your thermo!!! mine was out 10deg and i was consatnly ending up with 1020 finishes. got a new one made sure it was right and bam got it back where i wanted.
 
Do you know what the pH is, does not matter what the mash temp is, if pH is high you will have sugar complex issues and fermentation problems galore. A cheap meter is $10 in flea bay.

Are you also knocking out the CO2 when you test the wort? Grab a few cheap stainless bowls and tip between the 2 for a minute or so then come back and test ... otherwise the reading will not be correct.

What does the top of the ferment look like, can you see the yeast head crop up? Nothing to do with the liquid yeasts.
 
ohh ... and never trust a thermometer ...
 
/// said:
Do you know what the pH is, does not matter what the mash temp is, if pH is high you will have sugar complex issues and fermentation problems galore. A cheap meter is $10 in flea bay.

Are you also knocking out the CO2 when you test the wort? Grab a few cheap stainless bowls and tip between the 2 for a minute or so then come back and test ... otherwise the reading will not be correct.

What does the top of the ferment look like, can you see the yeast head crop up? Nothing to do with the liquid yeasts.
He is using soft Melbourne water, pH cant be to far out.
Nev
 
Some interesting points.
I could see that CO2 in the beer would affect a hydrometer reading; but not a refracto reading.
PH is spot on at 7.0, check with strips.
The first couple days of fermentation have a thick head of creamy bubbly activity in the fermentor, so looks fine there.

The theory of the thermometer being off fits, as it is common to all batches.If it is reading too high and i'm overcooking my mash; I could try the next mash 5deg cooler.
Anyway, i'll work through these suggestions, and update the post once i get to the bottom of it.
 
I thought that in Sydney too, I have never had issues at Rouse Hill or Wollongong. At Enmore f*ck me, had to throw in so much acid, at double the amount of CaCl2 and CaSO4 from the other 2 breweries (one same aquifer) we had a rest pH >6.2 without the acid addition. It was a nightmare to manage.

All we could put it down to was old pipes ...
 
gryphonkd said:
Some interesting points.
I could see that CO2 in the beer would affect a hydrometer reading; but not a refracto reading.
PH is spot on at 7.0, check with strips.
The first couple days of fermentation have a thick head of creamy bubbly activity in the fermentor, so looks fine there.

The theory of the thermometer being off fits, as it is common to all batches.If it is reading too high and i'm overcooking my mash; I could try the next mash 5deg cooler.
Anyway, i'll work through these suggestions, and update the post once i get to the bottom of it.
Water pH is 7.0 I assume :huh: not the mash !
 
/// said:
I thought that in Sydney too, I have never had issues at Rouse Hill or Wollongong. At Enmore f*ck me, had to throw in so much acid, at double the amount of CaCl2 and CaSO4 from the other 2 breweries (one same aquifer) we had a rest pH >6.2 without the acid addition. It was a nightmare to manage.

All we could put it down to was old pipes ...
If the pipes were old and the powers to be could they would make the feed water more alkaline to prevent the pipes disappearing .
Nev
 
gryphonkd said:
Some interesting points.
I could see that CO2 in the beer would affect a hydrometer reading; but not a refracto reading.
PH is spot on at 7.0, check with strips.
The first couple days of fermentation have a thick head of creamy bubbly activity in the fermentor, so looks fine there.

The theory of the thermometer being off fits, as it is common to all batches.If it is reading too high and i'm overcooking my mash; I could try the next mash 5deg cooler.
Anyway, i'll work through these suggestions, and update the post once i get to the bottom of it.
For the pH, is that your starting pH. If that is your mash pH you are in lots of trouble, but really the water pH going in matters little compared to what it falls to in the mash. You need to check mash pH to eliminate this issue.

But, you cant use a refracto once the fermentation starts, the booze throws off the reading. Only use these pre-ferment.
 
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