Wyeast 3787 - Surprisingly low attenuation

[lostcheesehead]

I recently kegged a Belgian dark strong that I fermented with the Wyeast 3787 High Gravity Trappist yeast, which I have had very good results with in the past. The OG was 1.083, so I was expecting an FG of 1.017 or lower, but it stopped at 1.021. Okay, that's not too shabby, I know, but my experience with fermenting Belgian tripels with that yeast led me to believe that I would get full attenuation or better.

Further, a buddy of mine brewed a Belgian imperial stout with the 3787, and it only fermented down to 1.035.

Has anyone else recently used 3787? Did you get the expected result? I'm wondering if Wyeast just made an off-batch, or maybe 3787 doesn't play nice with dark malts, or, or, or...

 

[ruger988]

Made a quad not long ago that came down to 1.008 from 1.092 with 3787. Love that yeast. What kind of temp range was your ferm in? Mash temps?

 

[lostcheesehead]

Mashed at 152 F, fermented at 67 F in my controlled chamber. Don't know about my buddy and his stout, but he's a very experienced brewer, so I don't think a hot mash or fluctuating fermentation temperatures can account for his FG either. I used to love that yeast, too, but this fermentation really caught me off guard.

 

[ruger988]

Good bit lower than I usually ferment at with 3787, not sure how that would affect attenuation but I doubt it would have that much impact. I'm assuming you had a good healthy pitch?

 

[lostcheesehead]

Yup, 2 liter starter made on a stir plate, and it behaved very well there. In fact, every part of the fermentation process appeared very normal, right up until the final measurement. I would consider writing Wyeast and asking about it, but I don't have the batch number or anything, so I don't think it would do much good.

 

[beergolf]

That yeast is famous for starting off fast and then slowing down and then taking a long time to finish. Starting off at 67 was ok but you really needed to raise the temp up at the end to finish it up. You did not mention how long you feremted it at. I am guessing that it was just not done yet, unless you have a lot of unfermentables in your recipe.

I hope you did not bottle it at that FG, because it will slowly tick off a few more points and then at best over carb the brew. So the worst case. you may have bottle bombs.

 

[stpug]

That yeast is famous for starting off fast and then slowing down and then taking a long time to finish. Starting off at 67 was ok but you really needed to raise the temp up at the end to finish it up. You did not mention how long you feremted it at. I am guessing that it was just not done yet, unless you have a lot of unfermentables in your recipe.

I hope you did not bottle it at that FG, because it will slowly tick off a few more points and then at best over carb the brew. So the worst case. you may have bottle bombs.

This has been my experience with 3787 as well. Those last several points come off slowly but surely.

 

[ruger988]

This has been my experience with 3787 as well. Those last several points come off slowly but surely.

I've always shot down pretty quick with 3787. That quad for example was down to 1.008 within a week and a half of brew day. Very tasty and nowhere near as hot as you'd expect for such a young 10%+ beer. 3787 is by far and a way my favorite brewing buddy.

 

[lostcheesehead]

No, no, it was kegged after a 14 day fermentation, so no fear of bombs on my end. I have not experienced the slow-approach FG out of 3787 before (like I said, I have made tripels with it, and they blazed down to their FGs in no time). Also, my buddy repitched his stout with some 3787 and let it ferment for another 4 weeks and still it refused to budge from an FG of 1.035 (he also made a tripel with 3787, and it fermented down to 1.008).

 

[beergolf]

No, no, it was kegged after a 14 day fermentation,

Good to hear it was not bottled. 14 days at 67 degreees is waaaaay to short for that yeast, especially with an OG of1.083.