Poor Attenuation

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Jay Cee

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A stout was brewed a month ago, and it's not fermenting out.

OG was approx 1.060
FG after four weeks is 1.030
Fermenting at 19 degrees

Some likely causes, in the comedy of errors that this beer has gone through.....

1. Wort was splashed everywhere into the dead space of fermenter, so I sprayed a lot of iodofor to clean it up. Approx 50-100mL would have gone into the beer

2. I pitched 1.5 sachets of S04 onto the wort, without thinking to distribute the iodofor solution that would have been on the surface.

3. Here's a clever next step in the saga. Wanted to measure something else that was exhibiting exothermal heat (not brewing related) so I pulled the temp probe out of my fridge to measure quickly. Forgot that I had done this, so the wort crashed low due to reading a constant temp of high 20's and the fridge running constantly.

3. After realising a week later, when there was almost no krausen, wort was brought up to room temp, racked to another fermenter to rouse the yeast, and another sachet of S04 and pitched (hydrated for three days in water this time).

It's still holding steady at 1.030 after a month

Theres been three pkts pitched so far, and I'm wondering what's happening. The only previous times when I have had a stuck ferment have been a batch of dead yeast (there was evidence from others that the batch from supplier was bunk), and when I mashed low due to faulty thermometer.

I'm considering my options, as to whether I should make an active starter from another pkt, or from some highly attenuating American liquid yeast, or just ditch the beer, as it's holding up production. I'm not comfortable in bottling it.
 
S-04 does not like being dropped below 16deg. I can tell you from personal experience where I had my heat belt slip onto the temp sensor of my STC-1000, resulting in the beer dropping down to about 14deg, all the yeast flocced out. I managed to squeeze a few more points out of it by giving the fermenter a good jiggle to rouse the yeast and jacking the temp up to 20deg. Also sometimes S-04 does not want to play fair, it can stall around 1.020 at the best of times.

Also what was the predicted FG of your beer? Your ferment may not be stuck, it might just be finished.....
 
1. Wort was splashed everywhere into the dead space of fermenter, so I sprayed a lot of iodofor to clean it up. Approx 50-100mL would have gone into the beer

2. I pitched 1.5 sachets of S04 onto the wort, without thinking to distribute the iodofor solution that would have been on the surface.

3. Here's a clever next step in the saga. Wanted to measure something else that was exhibiting exothermal heat (not brewing related) so I pulled the temp probe out of my fridge to measure quickly. Forgot that I had done this, so the wort crashed low due to reading a constant temp of high 20's and the fridge running constantly.

3. After realising a week later, when there was almost no krausen, wort was brought up to room temp, racked to another fermenter to rouse the yeast, and another sachet of S04 and pitched (hydrated for three days in water this time).

1. Wat? You sprayed sanitizing solution INTO your fermenter that contained your wort ready to ferment?

FYI.. there is no reason what-so-ever to ever need to do this. If you've cleaned your fermenter before pouring in your wort a little splashing of wort on the sides doesn't matter.. because you've already sanitized. If it's clean it's clean, if it's NOT clean, then wort splashing or no wort splashing, it's too late to fix it.

2. That should be ok.. i'm still scratching my head as to why you sprayed sanitizing solution INTO your wort filled fermenter.

3. The temp was obviously a problem. Your yeast would have been well and truly put to sleep. Although, why did you hydrate your re-pitch yeast for THREE DAYS?! The instructions are to hydrate for 30 MINUTES. I doubt your hydrated yeast would be very healthy after sitting in water with no food for them for three days.


Wow, what a comedy of errors.

The main issue was probably the temperature drop. If something like this happens there is no reason to rack to another fermenter. Just bring it back up to temp and re-pitch.

The other big issue is your three day hydration. Yeast only need to hydrate for a short time before they are ready to work. If they are hydrated and ready to go but are sitting in plain water then they will use up their energy reserves then starve or get sick. I can understand you may have confused a long re-hydration for the process for making a starter. Making a starter involved a few days in a sugar/wort solution so the yeast hydrate then start eating and re-producing and getting healthy. Sitting in plain water (no food for the yeast) is a problem. Don't do that.

The last issue, although probably not a huge factor is your spraying of sanitizing solution INTO your wort. Just think for a second before you do stuff like this. As I said, if you've cleaned your fermenter then it's clean.. right? Wort splashing doesn't change this. Don't spray sanitizing solution into your wort.

I suggest just bringing the temp of the fermenter up a bit (20C) and re-pitch straight into the beer (no three day starvation tortured yeast)
 
I sprayed a lot of iodofor to clean it up. Approx 50-100mL would have gone into the beer
This might be an obvious question, but... you used 50-100ml of Idophor SOLUTION (diluted 1:1000) or 50-100ml of Idophor?
 
I know nothing of the things which you speak. :lol: But am wondering if the addition of sanitizing solution changes the gravity of the wort? Which is to say, does the sanitizing solution have a high gravity?
 
I know nothing of the things which you speak. :lol: But am wondering if the addition of sanitizing solution changes the gravity of the wort? Which is to say, does the sanitizing solution have a high gravity?

How much sugar do you put on your sanitiser? feck me rotten
 
Yes, me too. Quite the series of brain farts. I can't even blame it on a newbie mistake, I have been doing this for years.

If it's any consolation, another very experienced brewer was standing there watching me do it. Let's blame him (you know who you are, BA :))

Ah ha!

What about the THREE DAY hydration / torture & starvation of your re-pitched yeast?
 
Yeast prefer a slightly saline, slightly acid medium if I recall correctly. You most likely have raised your ph level and the yeast don't like it.
 
I have been doing this for years.

If you've been doing it for years why were you concerned about wort splashing in a clean fermenter....also if you'd been in this game for years you'd know not to post such a strange brew related activity.
 
He could be a newby who has used all crystal grain for his stout. :D
 
Youre all ******* comedians. Half of you unable to actually read, another quarter not quite comprehending, but comedians nonetheless.


Go **** yourselves
 
Youre all ******* comedians. Half of you unable to actually read, another quarter not quite comprehending, but comedians nonetheless.

Go **** yourselves

Using a refractometer?
Since my hydrometer busted i have been forced to check FG with it, its always 1.020+ due to the alc content. (Which equates to ~1.012 etc etc)
 

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