Was fermenting 70-71 when we had a cold snap and brought my wort temp down to around 66/67 on the 3rd day. Back up to 70 the day after. Could that have made my yeast go dormant and not finish my beer as expected?
Could a sudden drop of 5-6 degrees cause my ale yeast to go dormant and not finish?
- Thread starter jetmac
- Start date
Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:
What makes you think your yeast went dormant and your beer didn't finish fermenting?
jetmac
Well-Known Member
FG is 1.028 after 6 days. About 53% attenuation
kanzimonson
Well-Known Member
Revvy makes a good point - the beer might be done already. You gotta take a gravity reading to know).
But also to answer your question, it's possible. Just don't get worried and think this is the difference between a syrup beer and a good beer... the difference would probably just be a couple gravity points.
But also to answer your question, it's possible. Just don't get worried and think this is the difference between a syrup beer and a good beer... the difference would probably just be a couple gravity points.
No, it's not the temp. That's not a huge drop....Ale yeast doesn't go dormant til the low to mid 50's.
And if it's only been fermenting for 6 days, I'm thinking there's anything wrong, it's just doing what it needs to do. Yeast don't really follow instructions all that well...being that they can't read they don't know that we humans think it takes them a week to ferment.
And if it's only been fermenting for 6 days, I'm thinking there's anything wrong, it's just doing what it needs to do. Yeast don't really follow instructions all that well...being that they can't read they don't know that we humans think it takes them a week to ferment.
I don't think there's any reason to "fix something" by adding more yeast when quite frankly I don't think there's anything wrong....It's only been going 6 days....I don't even begin looking at my beer's gravitys til it's been 10-12 days. And since I tend to walk away for a month normally I rarely even do that.
jetmac
Well-Known Member
I was leaning that way. My brewing mentor is old school(1994-present) and still uses a secondary/dry yeast.... blah blah.
BeernuT100
Well-Known Member
A 1 degree temp movement is enough to change the mood of yeast. However, in that temp range I do not see any reason for them to go dorment. They have merely slowed down. Possibly they are in shock but should recover in a few days. If not let us know.
-bn
-bn
motobrewer
I'm no atheist scientist, but...
i usually ferment in the low 60's.
just had a porter take all of two weeks to hit terminal.
just had a porter take all of two weeks to hit terminal.
TheBrewinator
Well-Known Member
During the winter, I ferment in my spare bedroom and we keep the house between 60-65 so the yeast are seeing a 5 degree swing between when we are home and when we are at work. I have yet to have a batch stall out. I recently had a brown (1.060) ferment to 1.020 after 2 weeks, I left it there for another 2 and it ticked away those last 4 points i was looking for to finish at 1.016 (my target). Just give it another couple weeks and you should be just fine.
jetmac
Well-Known Member
This is reassuring. My O.G was 62
jetmac
Well-Known Member
I checked the gravity Sat morn with my refractometer and it is still getting lower.
Update: I didn't check gravity today after 8 1/2 days, but I have a drylock (not an airlock) and when I squeezed it, a gush of CO2 escaped. With that said and a krauzen(?) ring still there and yeast flocculating on top, I think I still have fermentation. Glad I didn't add that dry yeast.
I think I am supposed to wait until that yeast drops to the bottom then let them work the bottom for a while. So all is not lost.
Update: I didn't check gravity today after 8 1/2 days, but I have a drylock (not an airlock) and when I squeezed it, a gush of CO2 escaped. With that said and a krauzen(?) ring still there and yeast flocculating on top, I think I still have fermentation. Glad I didn't add that dry yeast.
I think I am supposed to wait until that yeast drops to the bottom then let them work the bottom for a while. So all is not lost.
drgraffnburg
Member
Here's my concern. I have a stout using Irish Ale yeast. Fermenting at 68 degrees. After 1 week, it dropped from OG 1.060 to 1.034. My target is 1.020 (give or take a few points). I let it sit another full week, same conditions. It is STILL at 1.034.
Bubbling stopped after only 4 days, and I read in plenty of places here that when the bubbling stops, it is NOT an indicator that the yeast is done. I get that. But I figured in the last 7 days I should have still seen some gravity change.
So, when do I call it "stuck" and does anyone have any suggestions to kick-start it after 2 weeks in the primary?
Side note: I did sample the test amount I thieved from the fermenter. It tastes good and I would have no reason not to drink it. But I just want to understand what I can change? Seems this is not the first batch that has done this to me recently. I had an Amber stop well short of its FG as well.
Bubbling stopped after only 4 days, and I read in plenty of places here that when the bubbling stops, it is NOT an indicator that the yeast is done. I get that. But I figured in the last 7 days I should have still seen some gravity change.
So, when do I call it "stuck" and does anyone have any suggestions to kick-start it after 2 weeks in the primary?
Side note: I did sample the test amount I thieved from the fermenter. It tastes good and I would have no reason not to drink it. But I just want to understand what I can change? Seems this is not the first batch that has done this to me recently. I had an Amber stop well short of its FG as well.
Pilgarlic
Well-Known Member
I'd be surprised if a 3-4 degree drop by itself were enough to knock 'em down, though nobody can say. The temp might well have been the last straw among several variables (pitch rate, gravity, health of the yeast at pitching, wort ph) conspiring to knock 'em down.
Yukmay
Active Member
Occasionally I'll have a batch peter out on me a few gravity points high. I'm usually pleasantly surprised when a gentle rousing of the yeast via rocking or swirling the carboy gets things finished up nicely. However it usually over attenuates a few points on me if I rouse the yeast.
Be sure to review the brewing process if it's all grain. If somethings off you could be out of fermentables and still have a high gravity.
Be sure to review the brewing process if it's all grain. If somethings off you could be out of fermentables and still have a high gravity.
drgraffnburg
Member
Thanks, Yumkay. This is an extract recipe using LME. I gently swirl the buckets at least every other day just to rouse the yeast. I'm just not sure another week will yield any further fermentation since its been at the same gravity for an entire week.
remilard
Well-Known Member
Its really a lot easier to figure out what is going on if you do a forced ferment test (google it) which you have to choose to do before you have a problem so I would recommend it for every batch.
Since you didn't do one on this batch you have to taste it and guess whether it is underattenuated or rather a poorly fermentable wort.
Yukmay
Active Member
What temperature is it at? What yeast/malts did you use. Did you aerate it well?
MachineShopBrewing
Well-Known Member
My speculation is that this beer may have been underpitched/underoxygenated. A 1.060 beer with proper pitching rates and oxygen should be at terminal gravity within a couple days with the Irish Ale yeast. You say that after two weeks it is still at 1.034, I would say your ferment is stuck. That could be due to the aforementioned pitching rate or it may have been due to the temp drop. I was fermenting with WLP002 a while back and got the hairbrained idea that I was fermenting 1 degree F too high at 68 at the second day. I dialed back to 67 and it all flocc'd out and stuck the ferment. I have temp control +/- 1 degree F both heating and cooling so I know exactly what temp I had.
Golddiggie
Well-Known Member
Use a hydrometer for readings after you've pitched yeast into the wort. Once alcohol starts being produced, you won't get an accurate reading with a refractometer.
MachineShopBrewing
Well-Known Member
It will if you have the calculation for the difference and calibrate your equipment. I frequently use a refract for measurements during and after fermentation and they are accurate when cross checked with a hydrometer.
Similar threads
