Long fermentation

[acm28]

Hi guys,
it's not really a question but I would like to know what you would do to see if it meets what I intend to do.

I have a Belgium Ale (something between a double and a saison, a recipe I made myself, so it doesn't have a defined style) that has been fermenting for 7 weeks (or rather, it's still bubbling). Yes, I know, it probably finished fermenting 3 weeks ago, but since I'm not in a hurry, I didn't worry about the delay.
Last week, I checked the density and it was 1.010 (the first time I made the recipe, it ended up at 1.001). Since it was still 9 points short of the supposed density, I left it alone. Today I checked and it was 1.008 (more or less).

The change is probably not real and was just due to expansion, but since I'm not in a hurry, I think I'll wait and see the density next weekend, if the traffic remains the same.

I'd like to know if you agree with my approach or if you would do something different. I'd also like to know if you have anything to say about the big difference between the final density the first time and this time.

(Before anyone asks, the temperature here is between 15 and 18°C, I know it's not perfect but it's never given me any problems)

Thank you all in advance!

 

[brewSJ]

What's the yeast, a diastatic yeast like Belle Saison or a more ordinary Belgian-type yeast?

 

[acm28]

What's the yeast, a diastatic yeast like Belle Saison or a more ordinary Belgian-type yeast?

It's Abbaye from lallemand

 

[mac_1103]

There's nothing wrong with fermenting that yeast that cool, but I imagine that it could slow things down a little. What was the original gravity? Was it the same both times you brewed this recipe? Was everything else the same both times you brewed it?

 

[acm28]

There's nothing wrong with fermenting that yeast that cool, but I imagine that it could slow things down a little. What was the original gravity? Was it the same both times you brewed this recipe? Was everything else the same both times you brewed it?

It was 1,052, it was exactly the same density as the first time. Yes, everything else was the same.

 

[mac_1103]

98% attenuation with Abbaye (or almost any non-diastatic strain) really doesn't sound right. Your second batch seems more like what I'd expect.

 

[acm28]

So you think it has already fermented completely (and that the first batch had a strange FG?)
the fermenter is still bubbling, I know that doesn't mean it's still fermenting but since it still had a high FG (compared to the first batch) I thought it might still be fermenting.

Anyway, if it stays the same next week I'll bottle it (unless you really think it's already finished, in which case I'll probably bottle it tomorrow)

 

[MaxStout]

If you get two gravity readings the same, taken a few days apart, it's done. Lack of airlock activity is not a reliable indicator of when fermentation is complete.

I'm thinking your first batch that finished at 1.001 was due to either a measurement error, or there was contamination from some diastatic yeast (perhaps from a previous brew?)

 

[acm28]

If you get two gravity readings the same, taken a few days apart, it's done. Lack of airlock activity is not a reliable indicator of when fermentation is complete.

I'm thinking your first batch that finished at 1.001 was due to either a measurement error, or there was contamination from some diastatic yeast (perhaps from a previous brew?)

yes, I said right away that I knew that airlock activity did not mean it was fermenting.
There was definitely no measurement error because I actually have a photo of the moment I measured the density (I took it to send to a friend) .
As for contamination, I won't swear that it wasn't, although I sanitize everything before and after using it, that doesn't mean it couldn't have happened... in any case, if it did happen then it went well because the beer was quite good, and it didn't have any defects even months after being bottled.

Thank you all very much for your help! I now have more clarity. before, in my perspective this second batch had a high density and not the other one that had a low density. So now I know that the density value is within the expected range and the 98% attenuation in this type of yeast is very unlikely .

 

[acm28]

I just went to check and Lallemand actually talks about 83% attenuation for this yeast. A long way from 98%...

 

[Whisky River]

I just went to check and Lallemand actually talks about 83% attenuation for this yeast. A long way from 98%...

I think this is why others suggested there might have been a measurement error. There is no need to be dismissive of the possibility, we have all had measurements that have gone awry or don’t quite make sense. Staying open to all the possibilities that may have caused a problem is one of the best ways to learn.

In this case there could have been a number of possible ways the measurement could have been in error, the temperature of the wort may not have been accounted for or the wort may have been stratified causing the measured sample to be a different density than the rest of the batch.

Learning to use our tools with precision is one of the best ways to improve our skills as brewers, and one that doesn’t get discussed as much as it should. It can lead to much more consistent results and even if it doesn’t explain a particular problem it’s one less variable to worry about.

Best of luck and let us know how this beer tastes compared to the last batch. I think most people here would expect that if the last batch really attenuated that far it would have tasted significantly thinner than this one.

 

[acm28]

Just to update,
I bottled it today (I measured the density and it was at 1006 (but the temperature increased by about 3 or 4°C so that may explain the difference), I put it in 0.75L bottles, except for 6 bottles of 0,33L and a 4L mini-keg that I'm going to force carbonate.
The smell was great, I'll find out the taste soon.
I'll wait 3-4 weeks for the bottles, but I plan to try the mini keg very soon. I'll tell you how it is later.

 

[AlexKay]

Just to update,
I bottled it today (I measured the density and it was at 1006 (but the temperature increased by about 3 or 4°C so that may explain the difference), I put it in 0.75L bottles, except for 6 bottles of 0,33L and a 4L mini-keg that I'm going to force carbonate.
The smell was great, I'll find out the taste soon.
I'll wait 3-4 weeks for the bottles, but I plan to try the mini keg very soon. I'll tell you how it is later.

Always taste it when you package! And always drink the hydrometer sample.

The beer will change as it conditions, cools, and carbonates. But what it tastes like during the process is often very valuable information.

 

[ncbrewer]

When you check the gravity, you should also measure the temperature of the beer in the hydrometer cylinder and correct the reading for the temperature. This is especially true if you're using the readings to see if gravity is stable and ready for bottling. Hydrometer readings taken at different temperatures can't be compared.

 

[acm28]

Always taste it when you package! And always drink the hydrometer sample.

The beer will change as it conditions, cools, and carbonates. But what it tastes like during the process is often very valuable information.

I always try it and I tried it this time too, and the flavor was good. I didn't mention it because I think it's more "relevant" to know how it tastes when it's already carbonated.
For now I can say that the beer doesn't seem to have any defects and it seems to have some potential to be a good beer, but I won't guarantee anything until I see the final result.

 

[acm28]

When you check the gravity, you should also measure the temperature of the beer in the hydrometer cylinder and correct the reading for the temperature. This is especially true if you're using the readings to see if gravity is stable and ready for bottling. Hydrometer readings taken at different temperatures can't be compared.

I always do this, I said 3-4°C because last time I measured it but forgot to write it down and now I wasn't sure between the two values.
After the correction, the value remains the same as the last time if it was 4, and is slightly lower than the last time if it was 3°C.