Diagnosing a stalled fermentation

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

nhindian

Well-Known Member
Joined
Aug 12, 2013
Messages
146
Reaction score
5
Hi all, I brewed a 10 gallon batch of Yoopers Oatmeal Stout on Sunday and as of yesterday, there really wasn't much activity at all. I understand that it can still be working without visible signs, but there was still very little this morning. Some facts..

1. Made a 2750ml starter on Wednesday with 1 vial WLP-005 British Ale yeast (per Homebrewdad calculator, this should be more than enough cells)

2. Let the starter stir on a stir plate for 3 days until Saturday night. Had a very healthy krausen in the starter flask, rising all the way to the foam stopper in a 5000ml flask. Cold crashed overnight, decanted clear wort Sunday morning, and left out to warm up while brewing.

3. Pretty much nailed the OG at 1.053. Got a bit less volume than I wanted, so I got about 5.3gal in one carboy and 4.2 gal in the other.

4. Oxygenated with pure O2 for about a minute each.

5. Swirled flask to rouse yeast, eyeballed about half for each carboy. Tried to get slightly more into the one with more wort.

6. Had some airlock activity in both on Sunday and Monday. Slightly less on Tuesday.

7. Temps have been fairly constant 65 degrees

I'll be taking a gravity reading tonight, but I'd be surprised if it dropped much at all.

Thinking of pitching some dry yeast soon but any other thoughts?
 
What temp are you fermenting at? Ferm temp is a pretty important variable as I imagine you've seen around here, as low temps can really slow down yeast activity. And a gravity reading is a good thing for sure if it can be done without too much grief.
 
What temp are you fermenting at? Ferm temp is a pretty important variable as I imagine you've seen around here, as low temps can really slow down yeast activity. And a gravity reading is a good thing for sure if it can be done without too much grief.

Just edited it in! Around 65, Sunday was a bit cooler but never below 60
 
>.7. Temps have been fairly constant 65 degrees

Try raising your fermentation temperature to 70F. 65 may be on the cold side for the yeast. Once fermentation is going you can put the carboys back where they were.
 
A quick look at WhiteLab's page for that yeast shows that 65F is right at the low end for that yeast. Bump it up a few degrees like ArcLight says and once the yeasties have taken off you can put it back as there ought to be enough doing their thing to keep things going.
 
Thanks guys. I'll try doing that. Dont have a hot side to my ferm chamber but I guess I can try throwing a space heater in a closet and letting it go to town...
 
Take an SG reading first. I'd be surprised if it hasn't been fermenting.

Agreed! Will do so. Gotta take readings for a beer I made 2 weeks ago anyway.

Just surprised about the lack of krausen. Got some yeast rafts but they are sporadic.

Guess just psyching myself out - this is the first time I made a starter for 10 gal of wort so I'm paranoid I under pitched. I normally wouldn't care that much but I'm hoping to serve this at my wedding in May.

Every other time I've used liquid yeast and made my starters I've had high krausen that have always or almost always needed a blowoff. Those were even without my O2 wand too! Different strains of course though..
 
i had a porter once that didn't seem to do a damn thing during ferment. absolutely no krausen, never saw any airlock activity.

i took a gravity reading 3 days later and it was fermented out.
 
Take an SG reading first. I'd be surprised if it hasn't been fermenting.

So! Moment of truth... as a teaser, I also did a gravity reading on my Cream of 3 Crops batch. Went from 1.043 to 1.002 :drunk:

Gravity reading on the Oatmeal stout is... 1.020. So yeah, it has been fermenting - surprisingly well to be exact. FG estimate is supposed to be 1.016. I brewed this on Sunday - I wonder if I should leave it be or add a bit of heat to help it finish out?


As an aside, Yooper - based on the hydro sample alone, this is one of the best tasting batches I've ever done. I don't have too many AG brews under my belt, but it was amazingly flavorful; depths of coffee and chocolate and I can only wonder what a bit more time and carbonation will do to it. You got yourself a gem here! :rockin:
 
I've never used WLP005, but I use WLP002 (another English strain) all the time and the krausen I get is pretty weak, particularly on the lower end of the ideal temp range.

Sounds like you've got good news, though. I wouldn't warm it up yet as it's only been fermenting for what, 3 days? I usually wait until 5 days or around a week to bump the temp up a couple of degrees, if I do that at all.
 
So! Moment of truth... as a teaser, I also did a gravity reading on my Cream of 3 Crops batch. Went from 1.043 to 1.002 :drunk:

Gravity reading on the Oatmeal stout is... 1.020. So yeah, it has been fermenting - surprisingly well to be exact. FG estimate is supposed to be 1.016. I brewed this on Sunday - I wonder if I should leave it be or add a bit of heat to help it finish out?


As an aside, Yooper - based on the hydro sample alone, this is one of the best tasting batches I've ever done. I don't have too many AG brews under my belt, but it was amazingly flavorful; depths of coffee and chocolate and I can only wonder what a bit more time and carbonation will do to it. You got yourself a gem here! :rockin:

I'm glad to hear that you are pleased so far! It may not drop all the way to 1.016 but that's okay. If I use a less attenuating yeast, sometimes it stops at 1.020 or 1.018, but this beer is really good at those FGs anyway! I hope you like it in the end as much as we do at our house.
 
Back
Top