Fermentation stuck at 1.035 - already repitched once

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Shock29

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Hi everyone, This is my first post. I'm on my 6th extract brew (with steeping specialty grains). Trying to mimic a beer from a specific brewery, and the brewery gave me a few hints/tricks on fermentation and ingredients. Attached is a BeerSmith screenshot of the recipe I whipped up.

I brewed on June 23rd. Hit an OG of 1.069. Cooled to 70. Pitched a very very swollen smack pack of 1056. (After more reading, for anything over 1.060 it's suggested to use 2 packs, or make a starter. Neither of which I did).

Here's the interesting part. To bring out some of the fruity esters, the brewery instructed me to ferment at 78F... I have a temp controller, so that was no problem. Off to a quite high 78F we go.

Very active fermentation after 12 hours. Seemed to slow down after 2 days. Checked gravity 5 days after the brew, was 1.049 but that was using a refractometer. After using the refractometer calculator (https://www.northernbrewer.com/learn/resources/refractometer-calculator/), that works out to a SG of 1.035.

I left it for another 3 days. Same 1.035 reading... Decided to buy and rehydrate a full pack of US-05. Pitched that in. Stirred up the trub a bit. Checked gravity with my refractometer 5 days later - after the calculation, still 1.035. Has not budged...

I think I have two options:

1) Stay on course,rack to secondary and dry hop (then bottle) at a very sweet 1.035
2) Get another pack of yeast, make a starter this time, and pitch it.

Any advice?? I've fairly confident that if I took a hydro reading, it would also read 1.035.

Thanks in advance!!! :mug:

Amber Ale Brew.jpg
 

Sourz4life

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Did you calibrate the refractometer for alcohol. There are calcs to adjust for that as the reading is off when ethanol is introduced. May want to take a hydro meter to be sure, ale yeasts don't generally stall. Also how did you oxygenate the wort before pitching?
 

cshamilton

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With extract it is very unlikely that you are stuck that high. 1.020 sure, but that's really high. Check with a hydrometer and then know for sure.
 

kh54s10

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Did you calibrate the refractometer for alcohol. There are calcs to adjust for that as the reading is off when ethanol is introduced. May want to take a hydro meter to be sure, ale yeasts don't generally stall. Also how did you oxygenate the wort before pitching?
He did, and he linked to the one he used. I ran the numbers and came up with the same 1.035.

The only other thought is the zeroing of the refractometer. Was it set to read 1.000 reading distilled water?
 

g-star

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Check with a hydrometer.

If really stuck, you'll need to pitch an actively fermenting stirplate starter. Dumping smack packs, vials, or dry yeast in there is useless, as it is a low oxygen alcoholic environment which is hostile to new yeast growth.
 

GrogNerd

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8 days into a 1.065 beer?

yeast need more time. not just to finish fermenting, but there's other things they do, like clean up off flavors.

give it at least another week, then check gravity with a hydrometer
 
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Shock29

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Wow, thanks for the super quick response, gents !!

Did you calibrate the refractometer for alcohol. There are calcs to adjust for that as the reading is off when ethanol is introduced. May want to take a hydro meter to be sure, ale yeasts don't generally stall. Also how did you oxygenate the wort before pitching?
Regarding the calibration, I used the refractometer calculator to account for the ethanol that has been introduced (link in my original post). I oxygenated as I normally do - sit on the floor, Shake the 6.5 gallon carboy like a bat outta hell for 2 minutes (after racking from kettle to carboy via a funnel). I'll break out the Hydrometer now, but I've used the refractometer (and calculator) for other fermented brews, and have calculated a proper 1.09...

With extract it is very unlikely that you are stuck that high. 1.020 sure, but that's really high. Check with a hydrometer and then know for sure.
Same answer: I'll break out the Hydrometer now, but I've used the refractometer (and calculator) for other fermented brews, and have calculated a proper 1.09...

_______
Thanks again guys
 

kh54s10

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8 days into a 1.065 beer?

yeast need more time. not just to finish fermenting, but there's other things they do, like clean up off flavors.

give it at least another week, then check gravity with a hydrometer
It was 8 days at repitch then another 5 = 13 days and no change since day 5. It is done fermenting. Longer might help with flavors but the gravity will most likely not drop any more on it's own.

IDK other than checking the refractometer with distilled water, or checking with a hydrometer, I have no advice.
 
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Shock29

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He did, and he linked to the one he used. I ran the numbers and came up with the same 1.035.

The only other thought is the zeroing of the refractometer. Was it set to read 1.000 reading distilled water?
yep. 1.000 using distilled water, when I bought it.


Check with a hydrometer.

If really stuck, you'll need to pitch an actively fermenting stirplate starter. Dumping smack packs, vials, or dry yeast in there is useless, as it is a low oxygen alcoholic environment which is hostile to new yeast growth.
I think I should check it with a hydrometer, but since I've measured other post-fermented beer with it, and calculated 1.009, I'm afraid the hydro reading will be in the mid 30's too... No access to a stirplate or flask - might try and do a starter in a beer growler/airlock...

8 days into a 1.065 beer?

yeast need more time. not just to finish fermenting, but there's other things they do, like clean up off flavors.

give it at least another week, then check gravity with a hydrometer
Brewed on June 23rd (15 days ago). No gravity drop in the last 10 days, dispite repitching. I dont think it's gonna get any lower left as-is, unfortunately.
 

kombat

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More yeast won't help, something else is going on here. OP mentioned he had "very active" fermentation after just 12 hours, and even with the underpitch, fermenting that warm would encourage strong yeast activity. They're simply out of sugars to eat. My guess is he's measuring the gravity with a refractometer that is miscalibrated. As suggested, check it with a hydrometer. If you're determined to push it down a few points lower, you could pitch some high-attenuating yeast, like champagne yeast, but I don't expect it will make much of a difference.

That said, with the yeast underpitch and the hot ferment, I predict this will be a boozy, fusely, estery mess of a beer, but everyone's tastes are different, I suppose.
 

kh54s10

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yep. 1.000 using distilled water, when I bought it.
This may be your problem, you need to adjust the screw and reset to zero every time you use it! I take a look just before use and it has been as high as 1.020 before adjusting.

I have reset it to 1.000 at the first runnings, had 1.005 by second runnings, reset again and had 1.005 again preboil, reset again and read 1.010 before the OG reading.

You need to reset it every time. I just use my tap water which i believe gets me within .001.
 
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Shock29

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Just took a Hydrometer reading. 1.035. Right on the mark of the refractometer/calculator method. Further instills my trust in it.


More yeast won't help, something else is going on here. OP mentioned he had "very active" fermentation after just 12 hours, and even with the underpitch, fermenting that warm would encourage strong yeast activity. They're simply out of sugars to eat.
It does sound like they're out of sugars to eat... Not sure how that could be though.

My guess is he's measuring the gravity with a refractometer that is miscalibrated. As suggested, check it with a hydrometer. If you're determined to push it down a few points lower, you could pitch some high-attenuating yeast, like champagne yeast, but I don't expect it will make much of a difference.
Yeah, if it's only gonna get me down a few points, I'd rather try and make a starter with a whole pack of 1056, and try pitching that...

That said, with the yeast underpitch and the hot ferment, I predict this will be a boozy, fusely, estery mess of a beer, but everyone's tastes are different, I suppose.
There definitely a bit of a fusely, ester taste in comparison to other brews I've done, but it's not unbearable. The beer actually tastes very close to what I was going for, albiet sweeter...


This may be your problem, you need to adjust the screw and reset to zero every time you use it! I take a look just before use and it has been as high as 1.020 before adjusting.

I have reset it to 1.000 at the first runnings, had 1.005 by second runnings, reset again and had 1.005 again preboil, reset again and read 1.010 before the OG reading.

You need to reset it every time. I just use my tap water which i believe gets me within .001.
I wish that was the issue. Thanks for the tip though! I'll keep a close eye on this in the future.
 

Hoppy2bmerry

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What temp did you steep your grains? Outside of meter reading issues (and it seems you did things correctly) the place you could end up with unfermentable sugar is from the seeping grains. Just throwing that idea out there.
 
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Shock29

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What temp did you steep your grains? Outside of meter reading issues (and it seems you did things correctly) the place you could end up with unfermentable sugar is from the seeping grains. Just throwing that idea out there.
Great thought - I steeped at 150F for 30-40 minutes. There was a lot of grains to steep for this one. Just under 4lbs.

I'm currently leaning towards doing a 1056 starter and Kräusening as a last effort.
 
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