fermentation seems to have stopped

[squirrell]

Hi,

I put the following down 18 days ago.

Coopers lager tin
Coopers be1
250gms coopers ldme
10 cascade hops boiled for 15, 5 grams thrown in at the end of the boil, hops not strained therefore boil put into fermented with hop residue
Safale s05 yeast
Original gravity 1043

For the first week it fermented at between 20 to 25. Nice big Krause, but krausen still there after 7 days. I had to go on Easter holidays and returned 10 days later to find the krausen still there. I have taken a reading and the gravity is 1016. The krausen looks a bit sticky, but I tasted the hydrometer sample and it does not taste off, just a bit weak.

Any suggestions to refire up this baby?

 

[manticle]

There's a chance it's finished considering the ingredients.

Read this for ideas on how to proceed: http://www.aussiehomebrewer.com/articles/article130.html

 

[squirrell]

Thanks manticle, will try the suggestions. Is it possible for fermentation to have finished and the krausen to still be there?

 

[manticle]

Yes it is. US05 is one yeast that is well known for lingering krausen.

 

[JAM]

Is the air lock still bubbling? Or us it just krausen and no other activity?

 

[verysupple]

Is the air lock still bubbling? Or us it just krausen and no other activity?

Ha! For once the OP mentions gravity readings and doesn't mention (lack of) airlock activity, but someone still has to drag it into the discussion. Airlock activity is not at all a good indicator of fermentation - in fact, quite often it's not an indicator at all. Stick with the gravity readings.

As others have said, it might be finished and the krausen can stick around for quite a while afterwards, especially with US-05. Just take more gravity readings in a couple of days to make sure it hasn't moved and then you'll know for sure if it's done.

EDIT: You mentioned it was at 20 - 25 C during the first week. What happened after that? If the temp dropped a fair bit relatively quickly it might have put the yeasties to sleep. If that's the case you can wake them up again by raising the temp and giving the fermentor a gentle swirl to get them back in suspension.

If the temp didn't take a dive and stayed at 20 - 25 C, then I doubt it stalled and it's probably done.

 

[JAM]

Quite right you are very subtle..
But what i was thinking was, (and correct me if i'm wrong) that infection doesnt necessarily lead to over attenuation i.e. change in gravity?.. I swear i have had an infection before that hardly, if at all, changed the gravity but it kept on pumping out something through the airlock.... im not suggesting its an infection though!

 

[verysupple]

Quite right you are verysupple..
But what i was thinking was, (and correct me if i'm wrong) that infection doesnt necessarily lead to over attenuation i.e. change in gravity?.. I swear i have had an infection before that hardly, if at all, changed the gravity but it kept on pumping out something through the airlock.... im not suggesting its an infection though!

Well, considering that most bacteria, and all wild yeast, create CO2 by munching on sugar, I'm pretty sure if it was an infection the gravity would have changed. Although it is usually quite slow. It's much more likely that small, slow changes in temperature expand and contract the beer and air in the FV. Unless it's in a controlled environment, it usually contracts over night and you can easily miss the signs of contraction. When you're awake during the day it would expand and you see the airlock bubbling.

That's no certainty, but it's one plausible explanation.

 

[pk.sax]

If your airlock is installed on a properly sealed vessel with the fee ration being controlled at a stable temp, I cannot see much reason for the airlock to bubble except if it is still going.

Note- changing temp or ambient brewing is not good for guessing ferment by bubbling airlock. Carboys involve a bung and airlock and seal far better than plastic drums. Else, but kittens.

PS: beaten by verysupple.

 

[DU99]

:icon_offtopic: Like the new badges for staff

 

[manticle]

I don't.

 

[pat86]

1016 is definitely a bit high but could easily be the final gravity, especially with extracts which for me, seem to often finish higher (less fermentable content). I've had a beer finish at 1016, albeit with a diff. yeast and ingredients but the O.G. wasn't much higher than yours off the top of my head. Heavy beers will often finish up in that range, though not usually if they are PA or lager types.

I would still follow Manticles advice, as you never want to end up with bottle bombs, but otherwise it might just be done.

Would also recommend trying to avoid as much temp fluctuation in your next brews, even if you can steady it to between 20-22C, I am sure your beer will taste a lot better than 20-26. It would probably also help provide a more stable fermentation. 18C of course would be great but just do what you can to make it as predictable as possible if you can't dedicate a fridge to the cause yet!

 

[squirrell]

have put out the test sample as manticle sugegsted and given it a good shake up. Will test in 2 days, if no change in sample reading then will bottle ..... but think i will use PET bottles to be on the safe side!!
... dont know if its a coincidence, but the last time i had a high FG (1014) was also a coopers lager (although used the kit yeast then not SAF05). The brew ended up being undrinkable pretty much, really strong cidery twang (but great colour and head) .... it could also be that the weather is a little cooler ... or just bad luck

 

[squirrell]

so i ended up bottling this at 1015 FG and a month later it tastes awful - my verdict is its infected and the bottles are also a bit gushy so am ditching for safety rather than hold off. Lo and behold in my latest batch it seems again to be stuck at 1015 again after 8 days with a normal looking krausen that has not subsided - the beer tastes good though. I will of course give it a few days.

I'm nervous that this will end up being like my other 2 brews that stalled at 1015 - AWFUL!! For my previous 2 stalled brews the common demonitar seemed to be cold weather, however the temperatures have always been within 17 to 20 (and pitched at 24 to 26) so should be well within the recommended temp range of the yeast SAF05. My other brews all tended to ferment out in 4 days when the temp was at 22 to 24 degrees and they tasted great. From what i have read 18 to 20 is optimal for an ale yeast and leaving your beer in a fermenter for 2 weeks should actually improve your beer although i guess it leaves a greater chance of infection? Especially if i open up the lid every now and then to check its not infected? I can only assume that me getting impatient and opening the lid has caused this as i am thorough with cleaning.

 

[Ditchnbeer]

Lets clarify a couple of things. Pitch the yeast at the same temperature that the wort will start fermentation. In yr post you said you pitched at 24 to 26 but fermenting at 17 to 20. That is too larger gap for the yeast and it may go into 'shock'. Get them both at the same temp (i.e.19) and then pitch.

Also you are fermenting between 17 and 20. Does it start at 17 then slowly rise to 20 over 4-5 days? Or is the temp fluctuating between those two numbers over a 24 hour period? For better beer pitch an ale at 20 degrees and hold for approx. 4-5 days then let it rise over the next 4-5 days to 23, to 'finish off the beer'. It is critical to hold the temperature of the ferment and not let it fluctuate. A slow rise at the end assists the yeast to 'clean up' the beer.

 

[squirrell]

Ditchnbeer - its starts at 24 to 25 as per recommendations on the packet. I guess it would then gradually drop down to the 17 to 20 degree range over the next 12 hours or so. I dont have temperature control hence the temp fluctuation ie 18degrees at night, 20 degrees during the day. Its not ideal but from what I have read should not stop fermentation and the beer should still taste ok (its not like I am in the high 20s). Regarding the 'shock', if thats the case whats the best way to deal with it. Throw in some more yeast and give it a stir?

 

[unionrdr]

It's the temp fluctuating so much causing the problems. Too high a temp & the yeast produce the usual by-products of fermentation in larger amounts (referred to as PPM) that we can then smell or taste them. Then the temp drops by a significant amount & the yeast goes dormant,or "stalls". I keep dark tee shirts over my fermenters in spring through fall. Then an old jacket or coat in winter to help keep the temps from dropping too much. And pitching the rehydrated dry yeast within 10 degrees of current wort temp keeps the yeast from going through thermal shock. This leaves a lot more healthy cells that take less lag time to visibly start fermenting.

 

[squirrell]

so i guess i should warm it up a bit, re pitch some yeast (preferably rehydrated), gentle stir, and wait it out a few more days?

 

[Ditchnbeer]

With it currently stuck, I would swirl the fermenter around trying to get the yeast off the bottom to get those last points. If temp is 24 or above I wouldn't go any higher.

Going back to your reply to my first post here - in a perfect world for a generic ale I would want you to get the wort down to 20 degrees and then pitch the yeast. This will help make a better beer. I am not sure about this ' packet recommendations', 24 is on the high side.

If you really are interested in making a better beer, keeping your fermenatation temp stable is one of the first things to do. Use a fridge or build an insulated box. In winter use a lamp to keep the temp up to 20 degrees (for example) using a controller, in summer use the fridge to keep the temp down. Reduce or remove fluctuations of temperature, only let the ferment creep up 2-3 degrees over the 7-10 days that it takes to complete. Good luck.

 

[squirrell]

Thanks Ditchinbeer - i have done a couple of swirls and it looks like there is still fermentation, just pretty slow ie 1015 last wednesday, 1012 friday, 1010 Sunday. Beer tastes good to so looks like all ok, just slow due to cooler temperatures.