Stuck Fermentation... Help!

[Jack_O]

So this is my 4th brew. The first two went swimmingly. The 3rd one I had an issue with the brew not reaching its FG and the same has happened on my 4th brew. The 3rd one I ended up throwing away so don't want to make the same mistake here..

I've done some research and I'm putting it down to either my mash temp being too high or my ferment temp being to low. I live in the UK and during winter struggled to keep the fermenter temp up.

The recipe is a Black IPA I got off berewgr.com

American IPA Recipe - Black IPA EVE | Brewgr

I hit my OG more or less and got 1064.

The beer has been fermenting now for just over 2 weeks. I've checked the FG twice over the past few days and it seems to be stuck at 1026. Expected FG should of been 1016.

Im in abit of a rush to get this bottled as its for my father in laws birthday, however at the same time I obviously want it to be right.

I've stuck the fermenter in my airing cupboard were it is probably the warmest place in the house. However the FG is still hanging around the 1026 mark.

Couple of questions

1) If I were to bottle this now, would it create potential bottle bomb issues?

2) Will the beer still taste as good as it should? It will still come out at about 5% and I've tasted it flat and it seems OK.

I've also seen things on the Internet were you can shake the fermenter to try and wake the yeast up again as if I've had a low ferment temp they've likely gone to sleep.

Anyone with any advice, it would be much appreciated.

Cheers,

 

[VikeMan]

First order of business: Are you measuring with a hydrometer or a refractometer?

 

[McKnuckle]

(Assuming you used a hydrometer, so that SG can be trusted, but do answer that question.)

Mash temp, fermentation temp, and yeast strain are important variables here. What are the temps? I assume you used WY1056 as per the recipe. You're at 62% attenuation, vs. the "expected" 75%.

If you want to get more out of the yeast, you have to warm it up and re-suspend it. Warming means at least 20ºC, hopefully higher at this point. To suspend, swirl (don't shake) the fermenter. You don't want to introduce oxygen at this point.

If mash temp was on the high side, say 69ºC or above, you may be hosed. You can only get the yeast going again if there are fermentables remaining to be consumed, and a high mash temp limits that, sometimes significantly.

 

[Jack_O]

Hi Chaps,

Thanks for the reply.

Yes I use a hydrometer for measuring.

I used everything in the recipe as stated which included the yeast 1056 American Ale. I followed the instructions on the packet which advised leaving it out for 3 hours at room temp prior to pitching.

My mash readings were between 67-71°c during mash and i trusted my electronic thermometer was accurate. I wasn't too worried at the time about being a few degrees high but that may be the rookie in me..

I've little knowledge around the 'attenuation' % so not too sure what impact that has on the final product.

Assuming, I've gone wrong in the mash then, does that ruin the final product or will i still be able to produce a decent enough beer following carbonation.

 

[VikeMan]

My mash readings were between 67-71°c during mash and i trusted my electronic thermometer was accurate. I wasn't too worried at the time about being a few degrees high but that may be the rookie in me..

67C is fine. 71C is a bit high, and could go a long way toward explaining a not very fermentable wort.

I've little knowledge around the 'attenuation' % so not too sure what impact that has on the final product.

Apparent Attenuation:
(OG - FG) / (OG - 1)

The higher the number, the more sugars were converted to alcohol. Apparent Attention is driven by the yeast strain and the fermentability of the wort. The fermentability of the wort is driven by the types of grains used, the mash temperature, and the mash length.

Assuming, I've gone wrong in the mash then, does that ruin the final product or will i still be able to produce a decent enough beer following carbonation.

Assuming you've already got all the attenuation you're going to get, you'll still have made beer that's most likely drinkable, and you'll have learned something.

 

[Jack_O]

Thank you, that makes more sense now. Every batch of beer brewed is learning!

So from your experiences,

What do you recommend I do next to obtain the best beer I can with the situation I'm in..

Do I try and get the yeast going again by swirling the wort in the fermenter?

Or am I best just crashing and then bottling it now as it is unlikely I'm going to get any further activity from the yeast? As I said when I've tried it today (flat) it wasn't too bad. Carbonation should hopefully improve it also. And it's still at 5% now which makes it a decent enough beer?

 

[VikeMan]

What do you recommend I do next to obtain the best beer I can with the situation I'm in..

Do I try and get the yeast going again by swirling the wort in the fermenter?

Or am I best just crashing and then bottling it now as it is unlikely I'm going to get any further activity from the yeast? As I said when I've tried it today (flat) it wasn't too bad. Carbonation should hopefully improve it also. And it's still at 5% now which makes it a decent enough beer?

If the issue was a not very fermentable wort, swirling the wort/beer won't do anything. If the issue was something else (like premature yeast flocculation, due to a low fermentation temp (what was yours?)), then rousing it could help. And if the cause was low fermentation temp, you'll also need to increase it.

Until you're fairly sure what happened, I wouldn't recommend bottling. Fermentation could restart in the bottles, causing over-carbonation, gushing, and/or exploding bottles.

 

[Lubrication]

Had same problem last week also here in UK, solution was to rack the brew off the yeast into a clean bucket and re-pitch with an attenuative dry yeast, Mangrove Jack's M42. Gravity fell from 1.021 to an acceptable 1.015 in 5 days. My OG was 1.054, English Pale Ale. Brew temperature at 19C. Ready to bottle it now. Happy Brewing!

 

[Jack_O]

Had same problem last week also here in UK, solution was to rack the brew off the yeast into a clean bucket and re-pitch with an attenuative dry yeast, Mangrove Jack's M42. Gravity fell from 1.021 to an acceptable 1.015 in 5 days. My OG was 1.054, English Pale Ale. Brew temperature at 19C. Ready to bottle it now. Happy Brewing!

I may give this a go using Safale US-05. Should I put the full packet in or only a certain amount?

I've tried bumping up the fermentation temp but doesn't seemed to have had an effect on the FG.

Might be a silly question, so I apologise, but will too much yeast in the wort not cause issues when bottling and effect carbonation?

As I've not got too far to go now until I reach my FG.. Only 10 points.

If I were to add to much yeast would that take it way below the FG I'm targeting? Also would it make Bottle conditioning too active causing issues there.

 

[VikeMan]

Might be a silly question, so I apologise, but will too much yeast in the wort not cause issues when bottling and effect carbonation?

If I were to add to much yeast would that take it way below the FG I'm targeting? Also would it make Bottle conditioning too active causing issues there.

The answer to all of the above both is no.

 

[Jack_O]

The answer to all of the above both is no.

Vikeman, you've been a great help thank you!

 

[Lubrication]

Agreed. Answer to both questions is no. Try to leave behind as much of the old yeast as possible. Re-wet your Safale 05 and pitch it at the same temperature as the brew or slightly cooler. Let the fermentation progress as normal and bottle with your usual amount of priming sugar.

 

[Jack_O]

Ahh OK, so I will need to rack the beer into a new fermenter and re-pitch that way?

Rather than just adding the new yeast into the existing batch?

 

[VikeMan]

Ahh OK, so I will need to rack the beer into a new fermenter and re-pitch that way?

You certainly don't have to rack. Personally, I wouldn't. The yeast already in your primary isn't going to interfere with the new yeast.

 

[Lubrication]

Yes. Not a good idea to mix two types of yeast. Leave as much of the old stuff behind as you can. You will lose a couple of litres more than if you racked off the yeast just once but it's better than ditching the lot.
Also, I forgot to say use the whole sachet of Safale 05.
Good luck.

 

[VikeMan]

Yes. Not a good idea to mix two types of yeast.

Why?

 

[Lubrication]

I read this in James Morton's book 'Brew'. He says that the old yeast can produce 'markers' that tell the new yeast to flocculate prematurely.
This is an excellent book for beginners and experienced home brewers so I have no reason to doubt what he's saying.

 

[VikeMan]

I read this in James Morton's book 'Brew'. He says that the old yeast can produce 'markers' that tell the new yeast to flocculate prematurely.
This is an excellent book for beginners and experienced home brewers so I have no reason to doubt what he's saying.

Never heard of James Morton before. Does he have any qualifications, other than general author? I do see he was a lawyer and writes books about crime.

Are you/he talking about FLO gene "markers?" A yeast cell in suspension isn't influenced to flocculate by the genes of another yeast cell sitting at the bottom of the fermenter. Of course, it's possible for non-flocculated (non-settled, in this case) cells of the original strain to flocculate with cells of the new strain, but racking off of the already settled yeast cake won't prevent that anyway.

If you still believe what James Morton said, please provide more details. If he's right, I should be able to confirm it somewhere in the vast world of yeast flocculation related research papers and brewing texts.

 

[Lubrication]

This is a different James Morton. I believe he's a (medical) doctor who has also written books about baking. I am not a brewing scientist, I quoted his book in good faith and 'bow to your greater knowledge' as the saying goes!

 

[connell89]

In an earlier post, you stated your mash temp was 67-71 C (153-160F). If you started high 71C, your mash might have produced long-chain sugars which are hard to ferment. Did you try your beer after measuring SG? I assume it was sweet. You might never get to the expected FG. Just a thought.

 

[a_gunslinger]

Just to possibly save effort, try shaking up the fermenter first. I had one last month I thought was stuck. A good shaking roused the yeast and I got the extra points I was hoping for, or almost. Stuck at 20, shake and rouse, ended at 14. Kind of the same idea of racking to secondary, sometimes it rouses them. I would try that before any more aggressive maneuevers. If no luck, then onto some new yeast. Not sure I would do too much extra yeast as it can alter flavor if entire new massive colony introduced but dont have that much sugar to consume.

 

[Tom Foolery]

If I were in your shoes, I would first try raising the temp and give it a swirl. If that doesn’t get it going, I would pitch some Belle Saison on top.

 

[Camelot Legends]

Another thing to check. I had a similar issue when I began brewing where I would hit my OG on the mark but my FG was all over the map. Had a brew that ended lower than estimated but then had a couple that ended in the Mid 20’s. I delved into controlling my mash temps and fermentation temps. What’s your potassium chloride level? I read a bunch of brewing books but never found one that delved into it. I did find a report on an experiment done on bread yeast and at a high enough level, it inhibits yeast cells from doing their job. I changed my water source and never had an issue since with fermentation. Also, just an FYI, I tried just about all of the recommended fixes and never fixed any of the batches. Rousing yeast, warmer temps, dry yeasts, yeast in active fermentation even Champaign yeast and none of them worked. Also had issues with naturally carbonating in the bottles as well.

 

[VikeMan]

even Champaign yeast

FWIW, champagne yeast is a terrible way to try and finish a "stuck" fermentation. It's not good at eating maltose and can't eat maltotriose at all. The simpler sugars, which champagne yeast would use fully, are normally long gone by the time a fermentation is "stuck."

 

[Camelot Legends]

FWIW, champagne yeast is a terrible way to try and finish a "stuck" fermentation. It's not good at eating maltose and can't eat maltotriose at all. The simpler sugars, which champagne yeast would use fully, are normally long gone by the time a fermentation is "stuck."

Yes, it was just one of those that someone recommended so I tried it. Don’t do it, it doesn’t work. I think I got that suggestion from my LHBS.

 

[stealthfixr]

Glucoamylase can restart a stalled fermentation. I'd start with about 1/2 tsp mixed in distilled water, poured directly into the fementor. It saved a Porter of mine recently that stalled at 1.027, but 1tsp brought it down to 1.012. If 1/2tsp doesn't bring it down far enough, you can always add a little more at a later point, but be care and add incrementally to get the FG right where you want it.

 

[Jack_O]

I've actually bought this today from my local brew store. It's a turbo yeast to help with stuck fermentation. Will something like this help rather than an additional packet of safale yeast?

I've heated the fermenter up for the last 4 days now and it's been consistently at around 22-25°c. No change, I'm still stuck at 1026.

The beer does taste good so I'm worried my next step, whichever I chose to do will completely ruin the beer.

 

[VikeMan]

View attachment 715837
I've actually bought this today from my local brew store. It's a turbo yeast to help with stuck fermentation. Will something like this help rather than an additional packet of safale yeast?

I'm not familiar with it, but it appears to be marketed at a wine yeast, at least on some sites. If it really is a wine strain, there's a chance that it's also a killer strain. So, not only would it be unlikely to restart the fermentation (due to no simple sugars left, if fermentability of the wort was the original problem), but it might also kill off your primary strain and/or any beer strain you might try to add later.

What did your LHBS have to say about it?

 

[tyrub42]

Wow that's the first time I've seen Chinese on a yeast packet (and I live in Taiwan ). Does not inspire confidence tbh, especially since all it says in every language is "strong yeast" with no other info...

Agree with everyone else that if you mashed at 71 then your fg makes sense. Especially coupled with the robust malts that likely went into a black IPA, a 1.016 fg with your yeast would have been what I would have expected from 67 degrees. Also, that yeast doesn't flocc as hard as some of the common English strains so I doubt that's the issue and also doubt rousing will do much (not that you can't give it a shot). I think there are essentially four things you could try here (same things that Vikeman and others have mentioned).

1. Pitching some of that enzyme is likely the only way you're getting anywhere near your original target. This is also th easiest of these four. Potential danger is over attenuation but there's already someone in this thread that had great results with it.

2. Pitching some dissolved/sanitary dextrose to get your abv up and hope that the yeast then takes a couple more points off of the fg as well (I doubt it, but it's possible).

3. Getting the beer warmer to see if the yeast crapped out on you and can restart. This is completely dependent on how cool it got during fermentation. If it fermented at 16-18 I doubt this would be an issue but if it's sitting at 10 then it definitely could be.

4. Do step two, add maybe 5 points of dextrose, but BEFORE you do that, buy a packet of Nottingham, make a large starter, and pitch the whole thing into your beer at peak activity (vitality starter). Pitch the dextrose, then toss in the Nottingham starter. It may make a substantial difference or it may not, but at the least it should get your fg down a couple of points (Notty is higher attenuating than your original yeast AND it's active even down to like 10 degrees. It's a workhorse). It's a lot of steps but if it works out you'll end up with a beer that tastes great and has 6+ % abv.

I feel like #1, that enzyme, is the easiest, and that or #4 are the best chances for the beer to turn out well. Also what temp was the beer when it fermented, and how easy would it beer to warm it up to about 20?