Fermentation Issue in Triple Westmalle Batch 32 - Help!

[Asbjorn]

Hello everyone,

I'm currently working on batch number 32 and for the first time, I'm brewing a triple Westmalle. According to the recipe, the fermentation profile involves three stages. We started at 18 degrees Celsius for about two days, then increased to 20 degrees Celsius. The trouble began during the transition to secondary fermentation.

In my research, I found that secondary fermentation often refers to bottle fermentation, but it can also mean getting rid of the trub in the wort. So, I removed the trub, cleaned and sanitized everything, and put the wort back into the same fermenter.

During the primary fermentation, the gravity was declining rapidly towards the final gravity. However, after transitioning to the secondary fermentation, the fermentation rate slowed down significantly and is now almost stalling. According to Brewfather, it’s only 55% completed and has been sitting there since the 1st of July to the 22nd of July.

Can anyone advise on how I might save this batch? I'll attach a picture of the graph for reference.

Thanks in advance for your help!

 

[mac_1103]

What yeast are you using? OG of 1.072 and FG of 1.009 would be 87.5% attenuation. You're at 79% right now, which is within the expected range for many strains.

Lots of people will tell you that secondary fermentations are unnecessary or even harmful, or that 3 days post-pitch is awfully early to transfer to secondary even if you think it's necessary, but none of that is going to help you with this batch.

 

[Asbjorn]

What yeast are you using? OG of 1.072 and FG of 1.009 would be 87.5% attenuation. You're at 79% right now, which is within the expected range for many strains.

Lots of people will tell you that secondary fermentations are unnecessary or even harmful, or that 3 days post-pitch is awfully early to transfer to secondary even if you think it's necessary, but none of that is going to help you with this batch.

I completely agree with your assessment. I should have just left it as it was since it was doing fine. The "secondary fermentation step" got me a bit sidetracked. I've also read in some places that the so-called secondary fermentation in the bottle is misleading, as it's actually conditioning.

I'm not bottling; I use kegs. For this batch, I'm using Wyeast Labs Trappist High Gravity 3787.

This is my pilot batch, and I'm trying to work out all the quirks so it will be better in the future.

Im considering to order more yeast and add it to the fermenters, but it will take several days to arrive, i ordered the previous from Belgium.

 

[hotbeer]

What is the blue line on the graph? Temperature? 10°C seems a little cold for the 64-78°F (18-26°C) that is given for that strain of yeast. Though I know that 10°C goes against what you stated the temps are in the op.

Under pitch might be the bigger issue though you tried to build it up.

 

[hottpeper13]

I use a similar yeast for my Tripples and Quads. first I make a small Blonde at about 1.050 and pitch the whole cake on the bigger beer. I found that even thou these are diasticus positive they finish cleaner and faster with a stepped fermentation that ends at 78*.
Raise temp and wait as the diastic properties complete fermentation.

 

[Asbjorn]

What is the blue line on the graph? Temperature? 10°C seems a little cold for the 64-78°F (18-26°C) that is given for that strain of yeast. Though I know that 10°C goes against what you stated the temps are in the op.

Under pitch might be the bigger issue though you tried to build it up.

Correct, the blue line represents the temperature. I agree that 10°C is quite low for the 18-26°C range recommended for this strain of yeast. It makes more sense if we were conditioning. Normally, I condition my IPAs at low temperatures, but only once fermentation is completed.

The issue with the yeast was that one pack was only suited for 19 liters, and I had two packs for 50 liters. To compensate, I tried to grow more yeast and pitched it, but I think I discarded some yeast during the transition from primary to secondary fermentation. Lesson learned: I won't do secondary fermentation next time.

As we see, the yeast appears to be stalling. I'm considering increasing the temperature to around 20°C and perhaps adding more yeast to finish the fermentation before performing a proper cold crash.

 

[hotbeer]

Then just increase the temperature. The benefit of pitching the proper amount of yeast or even from over pitching are now in the area of too late to be much benefit, IMO.

There are plenty of yeast in there now. They are just shivering and not wanting to do anything.

 

[Asbjorn]

I use a similar yeast for my Tripples and Quads. first I make a small Blonde at about 1.050 and pitch the whole cake on the bigger beer. I found that even thou these are diasticus positive they finish cleaner and faster with a stepped fermentation that ends at 78*.
Raise temp and wait as the diastic properties complete fermentation.

Agreed, i will try to increase the temperature back to about 20 deg, and see what will happen, thanks.

 

[Asbjorn]

Then just increase the temperature. The benefit of pitching the proper amount of yeast or even from over pitching are now in the area of too late to be much benefit, IMO.

There are plenty of yeast in there now. They are just shivering and not wanting to do anything.

Agreed. Logically, this makes complete sense. I followed the recipe blindly and should have trusted my instincts, but this was my first Triple. Lesson learned.

 

[mac_1103]

Wyeast Labs Trappist High Gravity 3787

Apparent attenuation 74-78%. Definitely try raising the temperature as others have suggested, but I wouldn't expect it to get down to 1.009.

 

[CascadesBrewer]

Agreed. Logically, this makes complete sense. I followed the recipe blindly and should have trusted my instincts, but this was my first Triple. Lesson learned.

One pack of Wyeast 3787 is a good pitch rate for maybe 10L of 1.055 wort. For 50L of 1.074 wort, one calculator says you need almost 7 packs, and that assumes the packs are VERY fresh. https://www.brewunited.com/yeast_calculator.php The good news is that yeast is often pretty resilient, but if you plan to brew 50L batch sizes, you really need to step up your yeast game.

Personally, what I would do for a beer like this is:

• Pitch at around 20C
• Let the temp increase to around 24C during active fermentation
• Hold the beer in the 24C range until fermentation is complete and give it a little more time to clear (likely 3-4 weeks)
• Package. I usually bottle condition my Belgian beers. If kegging, you might be able to package a little faster.
• Age it in the bottle. It will likely improve after a few months.

 

[mashdar]

1. This beer probably has a bunch of candy syrup? IMO you subtract simple sugars (with ethanol adjustment) prior to assessing your apparent attenuation. Without sugar, the OG would be lower and FG higher, so 1.076 to 1.009 could be real. (In fact the CSI recipe for this beer is OG 1.080 FG1.008.)
2. That screenshot was still showing progress. You might hit terminal gravity in another month or two. Perhaps intended? But 10C is frigid for 3787.
3. If you were timing based on days in fermenter, don't. Generally you want to time based on attenuation. Maybe you were off to a slow start with yeast issues and jumped the gun on conditioning.

 

[johnsonpvb17]

Know your done by now, but I've got a similar batch with 3787, and this seems to work.
Used one pack and a 32oz starter.
Pitched and 3+ days @ 66, then slowly ramped to 75 and hold there
Got strong within hours, settles down, still steady at two weeks.
Transfer 3-4 days after it stops, whenever that happens.