Just share my experience, wonder if anyone else has noticed the same. Apologies it's a bit of a read....
I have been using WHC Funky Pineapple yeast, which is WHC's variant of WLP644 Saccharomyces "bruxellensis" Trois yeast. Although not officially confirmed, they fit as WHC describes it as a sacc yeast previously misidentified as brett, high (85%) attenuation, pineapple and funk aromas that increase with temperature. Slow prolonged fermentation that keeps creaping etc.
Anyway....
I've been using this with great results for my DIPAs. I grow up yeast on a lab stir plate in a low gravity wort (1.025-1.03) supplemented with yeast nutrient for 48hours in a temp controlled incubator, pitch 80% and seal and refrigerate the remainder to grow up again. I've done this previously with WLP4000 for 8+ generations with no change in performance, yeast growth etc. and keeps the yeast stress free in big beers.
My last 2 DIPAs with WHC Funky pineapple yeast followed the normal trois fermentation pattern. Vigorous fermentation peaking 24hr in that rapidly tales off by 48-72hours and then it creeps along for the next 20 days. In the final week its moving at a point per day, but does so very steadily without let up over the entire final week. I graph my fermentation using a BrewPi and accurately plot fermentation activity through the rise and fall of the delta between incubator and internal beer temps. Both followed exact same profile, reaching terminal gravity by day 20. 7.2% ABV All is fine.
I decided to make an 'weak' (1.077OG) imperial stout using this yeast. Similar OG, same temperature, approximated to be same pitching rate based on yeast mass. The activity started even more rapidly than normal but, instead of rapidly tailing off between 24 and 72hours, it declined more gradually and was still going reasonably strong (like a normal sacc yeast) at day 4. On day day 8 and day 10 I took a reading and to my surprise found it had completely finished. Subsequent readings over the weeks showed no change. Finished at 1.019 and a respectable 7.6%. 74% attenuated but this beer had a lot of flaked & roasted grain. On the same grain bill US-05 manages just a few points more so inline with expectations. Why did this yeast finish in half the time with a stout when it had behaved exactly the same on 2 previous IPAs that were more fermentable and similar (but slightly lower) OGs? Why did it ferment stronger for longer?
Now fast foward to last week when I started another DIPA (1.077OG) using 4th generation of this yeast. Back to normal fermentation profile. 24hr peak and between 48-72 hours it tails off and will inevitably creep along until day 20.
The only thing I can think is this yeast is stunted slightly by increasing amounts of hops (6.6g/L 80C whirlpool vs 1g/L 60min bittering only in RIS). At first I thought I had selected for a more rapid yeast, but my 4th beer with this yeast suggests not as its following the exact same fermentation pattern as gen 1 and 2. All beers are supplemented with yeast nutrient and zinc so I would be surprised if a RIS offered better growth media than an all pale ale malt bill. It is true that even in normal sacc, increasing hop compounds do decrease yeast biomass production at the higher end, but this isn't usually noticeable to the normal brewer even in your typical heavily hopped beer as it's so slight. Is Saccharomyces "bruxellensis" Trois particularly susceptible to hop compounds that are inhibiting it's growth perhaps?
Anyone had similar experiences?
P.S Brux trois works fantastically in an imperial stout - the tartness balances the sweetness without having to resort to big bittering IBUs to keep it balanced!
I have been using WHC Funky Pineapple yeast, which is WHC's variant of WLP644 Saccharomyces "bruxellensis" Trois yeast. Although not officially confirmed, they fit as WHC describes it as a sacc yeast previously misidentified as brett, high (85%) attenuation, pineapple and funk aromas that increase with temperature. Slow prolonged fermentation that keeps creaping etc.
Anyway....
I've been using this with great results for my DIPAs. I grow up yeast on a lab stir plate in a low gravity wort (1.025-1.03) supplemented with yeast nutrient for 48hours in a temp controlled incubator, pitch 80% and seal and refrigerate the remainder to grow up again. I've done this previously with WLP4000 for 8+ generations with no change in performance, yeast growth etc. and keeps the yeast stress free in big beers.
My last 2 DIPAs with WHC Funky pineapple yeast followed the normal trois fermentation pattern. Vigorous fermentation peaking 24hr in that rapidly tales off by 48-72hours and then it creeps along for the next 20 days. In the final week its moving at a point per day, but does so very steadily without let up over the entire final week. I graph my fermentation using a BrewPi and accurately plot fermentation activity through the rise and fall of the delta between incubator and internal beer temps. Both followed exact same profile, reaching terminal gravity by day 20. 7.2% ABV All is fine.
I decided to make an 'weak' (1.077OG) imperial stout using this yeast. Similar OG, same temperature, approximated to be same pitching rate based on yeast mass. The activity started even more rapidly than normal but, instead of rapidly tailing off between 24 and 72hours, it declined more gradually and was still going reasonably strong (like a normal sacc yeast) at day 4. On day day 8 and day 10 I took a reading and to my surprise found it had completely finished. Subsequent readings over the weeks showed no change. Finished at 1.019 and a respectable 7.6%. 74% attenuated but this beer had a lot of flaked & roasted grain. On the same grain bill US-05 manages just a few points more so inline with expectations. Why did this yeast finish in half the time with a stout when it had behaved exactly the same on 2 previous IPAs that were more fermentable and similar (but slightly lower) OGs? Why did it ferment stronger for longer?
Now fast foward to last week when I started another DIPA (1.077OG) using 4th generation of this yeast. Back to normal fermentation profile. 24hr peak and between 48-72 hours it tails off and will inevitably creep along until day 20.
The only thing I can think is this yeast is stunted slightly by increasing amounts of hops (6.6g/L 80C whirlpool vs 1g/L 60min bittering only in RIS). At first I thought I had selected for a more rapid yeast, but my 4th beer with this yeast suggests not as its following the exact same fermentation pattern as gen 1 and 2. All beers are supplemented with yeast nutrient and zinc so I would be surprised if a RIS offered better growth media than an all pale ale malt bill. It is true that even in normal sacc, increasing hop compounds do decrease yeast biomass production at the higher end, but this isn't usually noticeable to the normal brewer even in your typical heavily hopped beer as it's so slight. Is Saccharomyces "bruxellensis" Trois particularly susceptible to hop compounds that are inhibiting it's growth perhaps?
Anyone had similar experiences?
P.S Brux trois works fantastically in an imperial stout - the tartness balances the sweetness without having to resort to big bittering IBUs to keep it balanced!