Stuck Fermentation

I did my first partial mash in which I could not aerate the way I normally would. In this case I poured the cooled wert into my fermentor, then stirred for a minute or two then pitched the yeast. After four days I am not getting any bubbling out of my airlock and I am only down to 1.019 on my gravity reading. I startred around 1.050 and really should be down to about 1.013 or so. Using my brewing bucket to mash my efficiency was at about 55%. The temperature has been a steady 66 degrees for a Red Ale.

Thanks
Beerfan

Remove the vent tube or airlock, sanitize your fingers, cover the hole, pick up the carboy and shake that thing like a 5 dollar floozie on payday.

Do it again, every 8 hours until you see activity.

It happens, no big deal, but do not delay.

Your temps ok?

Cheers,

knewshound

From 1.050 to 1.019 in four days is quite respectable. I suspect you are not seeing bubbles because you have a slight leak, and the C02 is exiting via the leak rather than the airlock. Leave it another 4-5 days and check the gravity again. If it's still 1.019 you could have a stuck fermentation, or (more likely) you could have a problem with the hydrometer.
RDWHAHB.

-a.

what was your recipe? If you used a respectable amount of grain, but mashed it at a high temp, you could have created a lot of unfermentable sugars in your mash.

just a thought....

I agree with ajf......you obviously had fermentation. Probably just need to rouse the yeast a little. Go ahead and rack to secondary. That ought to re-suspend enough yeast to get things going some more. You should still be able to drop a few gravity points pretty easily.

Walker-san said:

what was your recipe? If you used a respectable amount of grain, but mashed it at a high temp, you could have created a lot of unfermentable sugars in your mash.

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Yes, what was your actual mash schedule?

Kai

Thanks everyone - I did shake it up last night and will check it again tomorrow morning. The recipe was a Red Ale and the temp seems fine. I guess I am used to reaching my final gravity quickly ( Usually about 3-4 days ). As far as my mash temp went it was a little high 165 degrees for about 10 minutes before I got it down to the 155 range, would that make a big difference?

Thanks again - This is great stuff
Beerfan

Wouldn't shaking it introduce too much O2? I would steal a sample and taste it, if its still sweet just moving the bucket/carboy will rouse the yeast. I would go with its done, move it to the seconday and let that yeast settle out.

Pimp Juice said:

Wouldn't shaking it introduce too much O2?

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Yes. Under no circumstances should you aerate a fermenting wort. Your wort was fermenting fine based on the drop in gravity...as mentioned, you probably did not have a good seal so the gases were escaping through an outlet other than the airlock. Hopefully you will not get any off-flavors associated with oxidation (it's not guaranteed you will, so don't give up on the batch by any stretch).

In the future, as a general rule you only want to aerate your wort while it is cool and before fermentation begins. Do not shake fermenting worts. When people say 'rouse the yeast', they really mean to gently swirl the wort just to get some yeast back in suspension.

Its been 24 hours since I swirled it up with no drop, I plan on racking to the secondary tomorrow and then I will leave it there for a few days. I guess I am normally looking at it being completed by now. Just out of curiosity does mashing change the fermentation time? Would it being at 165-170 degrees for the first 10 minutes of the partial mash reduce where my final gravity reading could end up?

thanks
Beerfan

Mash temperature/schedule will change the fermentability of the wort which in turn may affect the time of fermentation. However, for a partial mash recipe I wouldn't expect this to be a major issue unless a very significant portion of your fermentables came from the mash...I suspect most came from the extract.

Did you use a different brand of extract of the same one you usually use? Different brands have different degrees of fermentability. What was your recipe? Did it include lots of unfermentable components? That would contribute to a higher FG and your beer may actually be done fermenting.

When you say it would "normally" be completed by now, does that mean this recipe with these ingredients, or other recipes? It's hard to relate fermentation behavior of different recipes due to the differences in ingredients.

Different strains of yeast behave quite differently from each other, as well. Have you used this strain before and what were your notes from it? I would say that on average, fermenting an ale at 66F will take me at least 7-10 days. I had a Hefeweizen yeast at that temperature take almost 3 weeks to ferment.

It is also not uncommon for different samples of the same variety of yeast to take different times to ferment. I've had had yeast starters that have taken off very quickly, while some others (same yeast) have required several days of careful nurturing to get a strong fermentation going.

-a.

Patience grasshopper - after two days of nothing it started going again today - about every 25 seconds I get a bubble. I guess I will wait to rack into the secondary. Thanks for all of the advice, its great knowing that there are so many brewers with so much more knowledge than myself that can help.

beerfan

In the mean time if you had fermentation in your primary then there should be no o2 left inside. The co2 being heavier than o2 would have driven off the o2, so shaking/swirling the fermenter should not let any o2 back into the wort. IMHO

may I hijack this thread? Ok good - If a beer is racked after the krausen has fallen, but before it is 'all done' and then a bubble is only seen once every ten 20 minutes is this a 'stuck fermentation' or just the natural course it should take? Ps it is a wild hefe and only spent 5 days in the primary before being racked to 2nd.

NEPABREWER said:

may I hijack this thread? Ok good - If a beer is racked after the krausen has fallen, but before it is 'all done' and then a bubble is only seen once every ten 20 minutes is this a 'stuck fermentation' or just the natural course it should take? Ps it is a wild hefe and only spent 5 days in the primary before being racked to 2nd.

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What was the OG and what was the SG at time of racking? I usually go a week in primary, but I'm lazy and can only make myself work after a few beers on the weekend :cross:

mikey

uhh yah abaout that hydrometer reading. It mysteriously broke one day while no one was using it, I went to use it and it was cracked (not me did it) so I haven't the faintest the gravities are/were. The sample I tasted didn't taste "done" quite yeasty and sweet, but with a tinge of carbonation.

NEPABREWER said:

uhh yah abaout that hydrometer reading. It mysteriously broke one day while no one was using it, I went to use it and it was cracked (not me did it) so I haven't the faintest the gravities are/were. The sample I tasted didn't taste "done" quite yeasty and sweet, but with a tinge of carbonation.

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You really need the hydro info for us to answer correctly but let it go for a week and by then you should have a hydrometer or you can chance it. A young beer will taste a bit yeasty sometimes depending on the yeast strain used.

so if i post the reading you will be able to say whether or not its done without knowing the OG? Cool. Under normal circumstances when would I want to measure OG just before pitching yeast? Thanks

NEPABREWER said:

so if i post the reading you will be able to say whether or not its done without knowing the OG? Cool. Under normal circumstances when would I want to measure OG just before pitching yeast? Thanks

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It is not as simple, but based on the OG and mash schedule one can do a very rough estimate on what the FG should be.

Kai

NEPABREWER said:

so if i post the reading you will be able to say whether or not its done without knowing the OG? Cool. Under normal circumstances when would I want to measure OG just before pitching yeast? Thanks

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With the recipe, mash schedule, volume of wort, type of yeast, fermentation temps. etc. it is possible to estimate (read guess) what the OG might have been, what the FG "should" be and then work from there... without an OG reading, I'd check the SG every day and, when you get the same reading for 3 or 4 days in a row you can think about bottling... you really should use a hydrometer every time you brew to help prevent bottle bombs due to bottling too early...

You should check your OG right before you pitch your yeast, and make sure you correct for wort temperature (most hydrometers are calibrated for 60 F, so if you pitch at say 75 F there is a correction factor)

so if you'll post what you DO know about the brew, I'll try and work up some guesses for ya :cross:

later,
mikey

Hi again well it looks like my Current Gravity is 1.020 temp strip on the carboy says 64-66 and when I jostle the carboy I get a few bubbles in the airlock and it looks like there might be some yeast on the top that desends into the bottom when I swirl it.
Recipe as follows: 6lbs wheat LME - .5 lbs munich malt mashed for 60min at 160, sparged
at 170 - topped off to 5 gal. WLP380 I believe (the sppicy one) looks more like 4.5 gal after trnsfer from primary, sample has somewhat more viscous mouthfeel than water, with a slight sourness, a hint of tingle (carbonation?), but after swishing and spiiting, there is a beer aftertaste in my mouth.
I have consumed gallons of commercial wheats, but this is my first wheat brew. I guess Im a little baffled. I thought it would be easy as some people bottle from the primary, but maybe the complexity of the yeast is something I need to get used to working with,

NEPABREWER said:

but after swishing and spiiting,

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was the beer that bad that you had to spit it out???

NEPABREWER said:

Hi again well it looks like my Current Gravity is 1.020 temp strip on the carboy says 64-66 and when I jostle the carboy I get a few bubbles in the airlock and it looks like there might be some yeast on the top that desends into the bottom when I swirl it.
Recipe as follows: 6lbs wheat LME - .5 lbs munich malt mashed for 60min at 160, sparged
at 170 - topped off to 5 gal. WLP380 I believe (the sppicy one) looks more like 4.5 gal after trnsfer from primary, sample has somewhat more viscous mouthfeel than water, with a slight sourness, a hint of tingle (carbonation?), but after swishing and spiiting, there is a beer aftertaste in my mouth.
I have consumed gallons of commercial wheats, but this is my first wheat brew. I guess Im a little baffled. I thought it would be easy as some people bottle from the primary, but maybe the complexity of the yeast is something I need to get used to working with,

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how long has this thing been in the fermenters? 5 days in primary? then in secondary for how long?
my hw was in primary for 10 days around 68F and when i tasted it while racking to secondary, it tasted exactly how i hoped and dreamed it would taste. so 4 days later, i bottled it. HWs aren't beers that really need to be aged much.

this one spent 4-5 days in the primary and maybe 4-5 days in the secondary. My taste while transfering wasn't spectacular - milky lots of yeast still in suspension, spicy, a bit sour, but ok.

LOL - no, but I am still technichally on call - so drinking even a small amount is a no no.

alright - ive decided to put this bad boy out on the porch to warm it up to about 70 to see if that starts the bubbly again if not - ill measure gravity again on Fri and if its still at 1.020 da bizzle gets bottled.

Holla!!! anyone out there?

ok brewer heres what i think happened. the fermentation was stopped prematurely by something (maybe transferring to secondary) and then the yeast gegrew and began to eat the rest of the fermentable resulting in a carbonated beer. The reason I believe this to be the case is that the only time I see aitlock activity is when I roll the carboy and "shake" it up, it bubbles 5-10 times and then stops. I'll measure gravity in a few days and if its stable Ill bottle.

NEPABREWER said:

Hi again well it looks like my Current Gravity is 1.020 temp strip on the carboy says 64-66 and when I jostle the carboy I get a few bubbles in the airlock and it looks like there might be some yeast on the top that desends into the bottom when I swirl it.
Recipe as follows: 6lbs wheat LME - .5 lbs munich malt mashed for 60min at 160, sparged
at 170 - topped off to 5 gal. WLP380 I believe (the sppicy one) looks more like 4.5 gal after trnsfer from primary, sample has somewhat more viscous mouthfeel than water, with a slight sourness, a hint of tingle (carbonation?), but after swishing and spiiting, there is a beer aftertaste in my mouth.
I have consumed gallons of commercial wheats, but this is my first wheat brew. I guess Im a little baffled. I thought it would be easy as some people bottle from the primary, but maybe the complexity of the yeast is something I need to get used to working with,

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Well, the real question is how did they mash the Wheat LME... your .5 lbs of Munich @ 160 is gonna give you very little in the fermentable range... more body/flavor than sugars that the yeast can break down... that is a fairly high mash temp. as most I see quoted is 149-158 F... the lower the more fermentable the wort will be... if it was Munton's Wheat LME you should get a medium to high amount of fermentability from what I've read...

With ProMash I get an OG of 1.047 if 5 gallons and 70% efficency... so it could go as low as 1.014 given the yeast... again, don't know what the .5# Munich @ 160 F will do for sure and if the LME is mashed high, then 1.020 might not be bad at all... There is a chance that it is done... but I'd give it a day or 3 at the warmer temp just to see what happens...

And the flavor will change with age... RDWHAHB and let us know how it all comes out

later,
mikey

wow i had no idea that the lower the mash temp the more fermentable the wort. I will make sure tho follow that when I do my next batch which has got 3lbs ot 2 row

NEPABREWER said:

wow i had no idea that the lower the mash temp the more fermentable the wort. I will make sure tho follow that when I do my next batch which has got 3lbs ot 2 row

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I don't mean to be a jerk, but have you read any books on brewing--specifically, all grain?

There's plenty of good info to be had here, but to learn the basics you're going to have to do some reading.

Not to interupt but I just wanted to give an update on my initial post. The beer is great, a little lower on the gravity than what I wanted but none the less great tasting. A friend of mine tried a little out of the keg ( have not chilled it yet ) and stated that it was the best I have ever made. I now have a light Pilsner in the secondary that also was a little low on the ABV but that was an efficiency issue. Sparging and mash adjustment will be made on the next batch.

Thanks again for all of the help.
Dan

NEPABREWER said:

ok brewer heres what i think happened. the fermentation was stopped prematurely by something (maybe transferring to secondary) and then the yeast gegrew and began to eat the rest of the fermentable resulting in a carbonated beer. The reason I believe this to be the case is that the only time I see aitlock activity is when I roll the carboy and "shake" it up, it bubbles 5-10 times and then stops. I'll measure gravity in a few days and if its stable Ill bottle.

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When yeast produces CO2, it gets absorbed by the beer first. If there is enough CO2 in the beer already, it will gas out and be visible in the airlock. When the beer is sitting still, it can even become oversaturated with CO2 and this CO2 will be released when the beer is splashed around.

Now the bubbles that you see may come from the extra CO2 that is released by moving the carboy. If you can do this everyday, and get bubbles every day, the yeast must still be active and produces CO2. In this case you should also see airlock activity (which might be very slow though).

Kai

beerfan said:

Not to interupt but I just wanted to give an update on my initial post. The beer is great, a little lower on the gravity than what I wanted but none the less great tasting. A friend of mine tried a little out of the keg ( have not chilled it yet ) and stated that it was the best I have ever made. I now have a light Pilsner in the secondary that also was a little low on the ABV but that was an efficiency issue. Sparging and mash adjustment will be made on the next batch.

Thanks again for all of the help.
Dan

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So now it's a little lower gravity than you wanted?

Whatever, glad it turned out OK!