Stuck Fermentation Thread #879

[Sir Humpsalot]

I almost feel like maybe there should be a dedicated section just for "problem brews". Post your problems with your current batches and let the EAC's have their field day arm chair quarterbacking at your expense.

Here's my problem. Lager. OG 1.067; current SG: 1.036; After 2 weeks, it was at 1.036 and it didn't budge at 65 degrees over the next 5 days. I let it sit for those 5 days in warmer temps, figuring it could use the diacetyl rest anyway. After those 5 days, I racked it off to a secondary because I was concerned about the trub and I figured it should be about done.

To do the transfer, I used an autosiphon and very good sanitation and anti-oxygen practices- it was a very clean transfer, few bubbles. Then I took the hydrometer reading- No luck. Still at 1.036, but the diacetyl was noticably reduced. A day later, no additional fermentation. we're now at 2 weeks and 6 days, still stuck at 1.036. On the one hand, it was too early to transfer, but on the other hand, I am off the trub and have my 6.5gal primary back so I can use it for another batch this weekend.

So last night, after two weeks and 6 days in primary, I pitched a vial of white labs Mexican Lager yeast. 12 hours later, no action. 3 hours ago, I threw in a couple tablespoons of sanitized yeast nutrient (boil water, cool, add nutrient, pitch). Still, no action. I know I haven't waited long enough for the yeast nutrient to kick in yet, but I was just wondering if any of you folks had any ideas. I'm kind of out of ideas at this point.

 

[Sir Humpsalot]

Well, I guess nobody has an answer... so let me ask a different question...


What would you do if your lager was stuck at 1.036 after three weeks and pitching extra yeast with nutrient and warmer temps didn't seem to help?

 

[MA_Brewer]

Well, I guess nobody has an answer... so let me ask a different question...


What would you do if your lager was stuck at 1.036 after three weeks and pitching extra yeast with nutrient and warmer temps didn't seem to help?

Does it taste really sweet? I would imagine it does. Was the mash temp really high? I suppose if has a lot of unfermentable sugar, it doesn't matter how much yeast and/or nutrient you throw in there, it is going to stay.

I hate to waste beer, so I guess if you have an extra carboy or keg you could let it sit for a few months....maybe this is your excuse to get a new carboy!

 

[Sir Humpsalot]

Does it taste really sweet? I would imagine it does. Was the mash temp really high? I suppose if has a lot of unfermentable sugar, it doesn't matter how much yeast and/or nutrient you throw in there, it is going to stay.

I hate to waste beer, so I guess if you have an extra carboy or keg you could let it sit for a few months....maybe this is your excuse to get a new carboy!

It was an extract batch, so unfermentables shouldn't be an issue. It does have a slight sweetness to it, but not awful.... since the diacetyl rest, it's definitely drinkable...

I'm planning on letting it sit till May anyway, so I am in no hurry... but I was hoping to lager it, but I can't do that while it's still sitting at 1.036. So I will be getting a new carboy either way. I was just hoping to be able to you know, actually have a beer that I could have confidence bottling up and have ready for May...

 

[Sir Humpsalot]

24 hours after the repitch. Temp is up to 71 degrees. Activity in the airlock is minimal. About a bubble a minute, but I guess that's an improvement.

Frustrated, and knowing I shouldn't obsess any more, I went and threw together a Scottish Ale from NB. 12 hours later, it's not fermenting either.


My first batch worked perfectly despite hundreds of embarrassing problems. My next two have given me problems despite going smoothly. What gives?

 

[lefteye]

A bubble per minute sounds good , for starters. Sounds like you're doing all that's possible to save the batch.
Good luck - keep us posted to the strange goings on in yr carboy.

 

[ayrton]

Did you use Laaglander extract? They have a very high rate of unfermentable sugars.

 

[david_42]

For the lager, I suspect the temperature is too high for the yeast to work. Lager ferments can run a month without any problems at the proper temperature. Either bring the temperature down to the correct range and wait for it or pitch some Nottingham on it to dry it out.

 

[Sir Humpsalot]

I did not use laaglander.

I was trying to follow the recommended procedure of keeping the temp high for initial fermentation, then bringing it cooler once fermentation has begun to take place. And I'm not really sure that a bubble per minute really counts as active fermentation. Heck I reaerated. For all I know, it's still degassing.

And I thought lager yeast will work at higher temps, but it just results in an "ale-like" taste. I'm willing to take that trade off if it means I don't get a stuck ferment. I've got plenty of time between now and May... I can afford to be patient....

 

[Sir Humpsalot]

Ok. I totally failed at obtaining fermentation with the repitch and the aeration. 48 hours later and I've got bupkus. I might as well consider the batch scrapped... unless....



What do you think about maybe throwing some of the krausen from my scottish ale into the lager? I mean, just ANYTHING to get some fermentation. Is it worth a shot? Any better ideas out there?

 

[thedaler]

Well, I definitely don't think the batch is scrapped. Even though the final gravity isn't what you wanted and the beer might not taste like what you wanted, you still have about a 4% ABV beer on your hands with a FG at 1.036. It might actually still taste really good. You just now have a sweet, full lager instead of a drier one. I know I'd drink it.

 

[Sir Humpsalot]

Well, I definitely don't think the batch is scrapped. Even though the final gravity isn't what you wanted and the beer might not taste like what you wanted, you still have about a 4% ABV beer on your hands with a FG at 1.036. It might actually still taste really good. You just now have a sweet, full lager instead of a drier one. I know I'd drink it.

But I can't bottle it. So I can't carb it. So it's a flat beer. I'd rather turn it into an ale. If I can...

 

[Vermicous]

I know some people have had good result using beano with stuck fermentations, but I can't speak from personal experience.

 

[boo boo]

Dunno if you had bad yeast, never pitched enough yeast because you didn't make a starter, never aerated your wort properly, temperture you pitched at.
I have never had your problem with wort but I did with a wine once and redid with a starter and it finished at the proper FG.

I'd try pitching a pack of S-23 lager yeast or other dry lager yeast (without aerating) and leave it for a week or so.

When you pitch a vial or smack pack of liquid yeast you should make a starter and aerate your wort well. Also removing the wort from the primary yeast didn't help.
Then again I have never had your problem with wort like I said.

 

[ayrton]

I used Beano once. I can't even remember when I added the stuff, but my beer went from 1.036 down to 1.018 in three weeks (I just bottled it last night). It takes for-freaking-ever, but if you have the time and patience, it'll come through.

 

[Yooper]

I guess I would try some lager yeast one more time. Make a monster size starter, and pitch it into the beer. keep it at the high end of the yeast's recommended fermentation temperature and proceed. No more aerating, though! You'll get cardboard flavors.

If that didn't work, I'd go ahead and use 2 beano.

It's good that you're so patient- patient is a virtue with lagers!

 

[clayof2day]

Proper pitch rate is going to be very important when doing your lagers. Especially if you are cold pitching, i.e. pitching at your fermentation temperature. Big starter, my friend. I would say 99% of stuck fermentations are caused by insuffiecent number of healthy yeast cells.

I would give the properly rehydrated S-23 a shot, and if THAT doesn't work go for the Beano. If that many different yeasts won't ferment it, my guess is it is unfermentalbe and the Beano will help.

 

[Sir Humpsalot]

Liquid yeast, no starter, aerated for 10 minutes before pitching the german lager yeast and another 10 mins before pitching the mexican lager yeast. Temps are around 70 right now, hoping to get something going.

I guess I will do a monster starter tonight and try that. ::sigh::

 

[Yooper]

Liquid yeast, no starter, aerated for 10 minutes before pitching the german lager yeast and another 10 mins before pitching the mexican lager yeast. Temps are around 70 right now, hoping to get something going.

I guess I will do a monster starter tonight and try that. ::sigh::

I think the big starter will be the ticket- I really do. Lagers require big, big starters. I did a gallon starter for my maibock and it was still pretty slow going. You can make the starter at room temperature, and then pour off the beer and then chill the yeast down and put it in fermenting temperature wort. If I wanted to ferment at say, 50, then I'd chill the yeast down to 48 and then pitch it into the 50 degree wort.

good luck!

 

[Sir Humpsalot]

Well, I did a half gallon starter. It's be about 6 hours now and it's starting to ferment. We'll see how it looks when I get home from work tonight.

 

[Sir Humpsalot]

Just had a thought/question...

What's the difference in bubble rate between a quart starter and a 5 gallon batch of beer? For example, if a gallon starter is bubbling at 1/5th the rate of the 5 gallon batch, are those two batches at (relatively speaking) the same level of fermentation?

Seems to me that at 1/5th the volume of fluid and with the "thimble" of the three-piece airlock being equal, the starter should bubble at 1/5th the speed of a fully-fermenting batch.



The only reason I ask is that with a quart starter, I'm at a bubble every 60 seconds, which, according to my logic, is roughly akin to a bubble every 6 seconds. Remember, I pitched 5 gallons' worth of white labs' yeast into a quart starter. And since I'll be gone for the next 12 hours, I just want to be sure I'm not going to miss the best time to pitch the starter.


Then again, I guess a day late is better than a day early, eh? Or am I over analyzing it?

 

[joshpooh]

I would try priming the beer with corn sugar or DME as if you were bottling it, but of course leaving it to ferment. I had the same problem once, and added 4 cups of corn sugar boiled in water. I also added new yeast though. So I'm not sure that is actually what fixed the problem, but it seems logical that if it gets yeast going enough to carbonate when fermentation is complete, it should get them going enough to unstick stuck fermentation. Looking back my 4 cups was probably excessive though. It didn't really hurt anything other than making a beer with alot more alcohol than I wanted. You might want to try adding corn sugar or DME and yeast though. It worked for me.

 

[Yooper]

Just had a thought/question...

What's the difference in bubble rate between a quart starter and a 5 gallon batch of beer? For example, if a gallon starter is bubbling at 1/5th the rate of the 5 gallon batch, are those two batches at (relatively speaking) the same level of fermentation?

Seems to me that at 1/5th the volume of fluid and with the "thimble" of the three-piece airlock being equal, the starter should bubble at 1/5th the speed of a fully-fermenting batch.



The only reason I ask is that with a quart starter, I'm at a bubble every 60 seconds, which, according to my logic, is roughly akin to a bubble every 6 seconds. Remember, I pitched 5 gallons' worth of white labs' yeast into a quart starter. And since I'll be gone for the next 12 hours, I just want to be sure I'm not going to miss the best time to pitch the starter.


Then again, I guess a day late is better than a day early, eh? Or am I over analyzing it?

I have no idea- but my thought is this: The fermentation is the same speed whatever size it is. Whether it's one gallon or 10 gallons, the rate of fermentation is the same. So, it would bubble the same amount, releasing co2 at the same speed. And you didn't pour 5 gallons worth of yeast into a starter- the whole point of doing a starter is to grow enough yeast for the 5 gallons!

Anyway, you can pitch your starter anytime after high krausen. I usually ferment mine out completely, then chill it, so I can pour off the spend wort. The more yeast you have, the better the fermentation will take off. Check the recommended fermentation temperature of that yeast, and keep it at the high end of that temperature range until it takes off.

 

[Sir Humpsalot]

I did what you said Lorena... except for the part about the pouring off of the beer. At an anticipated 6.7+% ABV, I decided I'd rather have a little more that's a little weaker.

And yes, I DID pitch the whole 5 gallons of yeast into the starter... and the moment I pitched it, all fermentation stopped. Cold. Is that normal? Do the yeast pause for a while as they reacclimate? The starter was exactly next to the primary, so the temps should have been more or less identical. Anyway, 8 hours later, no new krausen in the primary. No bubbles from the airlock.

I've dropped 3 full batches of yeast into this thing, including one with a 3/4 gallon starter. It's coming up on 4 weeks in primary. It's been sitting in warm temps for a week or more trying to get fermentation started.


The only think I can think of is that I lost about a tablespoon of starsan into the beer.. but that shouldn't give me a stuck fermentation 3 weeks later... So I'll give it another day for fermentation to start, but I'm thinking it's time to do a search on using Beano...

 

[Yooper]

And yes, I DID pitch the whole 5 gallons of yeast into the starter... and the moment I pitched it, all fermentation stopped. Cold. Is that normal? Do the yeast pause for a while as they reacclimate? The starter was exactly next to the primary, so the temps should have been more or less identical. Anyway, 8 hours later, no new krausen in the primary. No bubbles from the airlock.

I'm not sure I understand exactly what you are saying here. Yes, the yeast take a bit to acclimate, but you are pitching active yeast into the same temperature wort and it should ferment. Remember though, that lagers are much slower and you can not judge fermentation by airlock activity. Lager yeasts are also bottom fermenting, not top fermenting.

The only thing I can think of is this- are you 100% sure your hydrometer is correct at 1.020? (Corrected for temperature?) If you're fermenting at 50 degrees, you have to make a small adjustment to the s.g. Also, check your hydrometer in water to make sure it's right. And make sure to degass your sample before reading it. Put the beer in the hydrometer test jar, stir, stir, stir to degas and let warm up to 60 degrees. Then check the s.g. Gas in the sample will give false (high) readings.

One last thing, taste the beer- does it taste a bit sweet? If it tastes right, maybe it's fermented out.

 

[Sir Humpsalot]

Thanks for all your help, Lorena.

Yes, I tested the hydrometer in water... and in the starter when I was making it... it's accurate. And I degassed too. And what I meant was that I pitched the whole vial of yeast (for a 5 gallon batch) into the starter.

And, 12 hours after pitching the starter into the carboy, I had NOTHING going fermentation wise. Less than a bubble an hour. I understand that lagers are slow, but less than a bubble an hour? That's not fermenting, that's degassing right there. (and because I'm sure somebody is wondering how you measure a bubble per hour, the answer is that you use a better bottle and squeeze a bubble or two out of the carboy so the water on both sides of the thimble in the airlock is even.. then wait and see how long it takes for the water to be replaced by air).


So, about 2 hours ago, I crushed up two Beano tablets in hot water, cooled it, and pitched it into the carboy. within 20 minutes, I had better than a bubble per minute. FINALLY!!!!!!

So I guess I just had a lot of proteins left in there. For what it's worth, my recipe included 6lbs of Munton's Light DME and 3.3 lbs of cooper's Light LME. It shouldn't have gotten stuck.. but there ya have it. It was a full wort boil, one hour.

 

[Yooper]

Well, the beano trick does work. Good that you got it going again- glad to hear it!

 

[Kadmium]

Just my thoughts on pitching yeast into a stuck fermentation. When you add yeast into an allready half fermented wort, your pitching the yeast into a toxic environment. The yeast eat the yummy suggars and pee out the toxic alcohol. Alcohol is what kills the yeast (hence some strains dont attenuate very well) so pitching yeast into a half fermented wort is pitching them into a half toxic environment... I would say this will cause the yeast you repitch to have a lag time... I dunno, just my thoughts, I might be wrong..

 

[clayof2day]

I think someone mentioned it previously, but the beano will work slowly. You'll need to give a lot of time to work or it will keep producing fermentable after you bottle and you could get some gushers. I would give it a nice long secondary after the beano.

Good luck!

 

[Sir Humpsalot]

I think someone mentioned it previously, but the beano will work slowly. You'll need to give a lot of time to work or it will keep producing fermentable after you bottle and you could get some gushers. I would give it a nice long secondary after the beano.

Good luck!

Thanks for the heads up... I'm giving it till April.