WLP644. Will it ever stop fermenting?

[Elixer]

Hi, my first post here.

On the 17th of April I brewed a batch of a NEIPA and used WLP644 Saccharomyces Bruxellensis Trois for pairing its fruity flavor characteristics with the fruity hop flavors.

Batch size: 17,5 liter (4,6 gallon)
OG 1.072
IBU: 83 (according to BeerSmith)
Measured efficiency: 74%

Malt bill:
2200 g Pilsner malt 40,1%
2100 g Pale Ale malt 38,3%
900 g Flaked Oats 16,4%
190 g Melanoidin malt 3,5%
100 g Carapils 1,8%

Mashed at 66C (151F) for an hour.

Hops:
10 g Columbus 30 min boil
15 g Columbus 5 min boil
25 g Nelson Sauvin whirlpool at 95C (203F) for 25 min
25 g Citra whirlpool at 95C (203F) for 25 min
25 g Mandarina Bavaria whirlpool at 95C (203F) for 25 min
25 g Nelson Sauvin whirlpool at 65C (149F) for 25 min
25 g Citra whirlpool at 65C (149F) for 25 min
25 g Mandarina Bavaria whirlpool at 65C (149F) for 25 min
25 g Nelson Sauvin dry hop for 10 days
25 g Citra dry hop for 10 days
25 g Mandarina Bavaria dry hop for 10 days
25 g Nelson Sauvin dry hop for 6 days
25 g Citra dry hop for 6 days
25 g Mandarina Bavaria dry hop for 6 days

Efficiency was higher than expected. I was expecting about 65% with all the oats. I decided not to water down the wort and make a double IPA instead.

This the first time I have used this yeast strain, formerly named Brettanomyces bruxellensis Trois. According to the White Labs it's packaged as normal Saccharomyces and the pitch rates are the same as Saccharomyces strains. Id did however make a 1 liter starter.

Fermentation took off in less then 24 hours. After a two days I added the first dry hop addition and four days later the second addition. By now I was hoping that the fermentation would be finished for the largest part, but it kept on fermenting.

On the 29th of April, 10 days after the first dry hop addition, it was still fermenting, so I decided to rack it off the hops into a glass carboy.
The gravity reading was 1.017. Which correlates to 75% apparent attenuation. According to White Labs this yeast should attenuate to 85%. That would mean it should get down to approx. 1.010

Now three weeks after pitching the yeast, it doesn't show any signs of slowing down. Still bubbling at a rate of once per every 8 seconds. Same as 10 days ago. I'm a but puzzled by this because I never had a yeast taking this long to ferment a beer with a OG of 1072. Since there isn't much information about this yeast strain regarding its fermentation time, I thought I'd ask about your experiences regarding fermentation time with this strain.

 

[Elixer]

Despite the risk of oxidation, I just went on with it and took a gravity reading today. It's now sitting at 1.014. Three points down in eleven days. I'm not sure how long that took. Could be eleven days or three days.

I'll let it sit in the carboy until this weekend before taking another gravity reading. If it's stable I'll assume it's safe to bottle. Perhaps I should aim at the low side of carbonation in case the yeast decides to take it down another point.

Still bubbling at a rate of about once per 8 secs though. Could all the CO2 going through the airlock just be the result of off-gassing?

--


The sample taste great by the way. Orange to yellow in color and very hazy. Extreme fruity/citrussy at first which makes place for a bit dank and medium bitter aftertaste. Medium to full bodied and silky smooth, thanks to all the oats. Will probably a bit more lighter bodied when carbonated.

 

[filthyastronaut]

I have an IPA with this yeast in the carboy right now. It took off really quickly and all signs of fermentation disappeared after the third day. It has been dry hopped twice and is slowly "clearing" (I use that term lightly, it's hazy as hell). I don't take gravity readings beyond OG and FG, so I am playing a bit of dangerous game with it. Planning to bottle this Saturday. It seems to be just like any other Sacc fermentation I've seen so I'm really not too worried.

I pitched it straight out of the package into 2.5 gallons of 1.057 wort @ 70 degrees, letting it free rise. Mashed @ 152. I'll let you know my results. With the high attenuation, it should bring it down to around 1.008.

 

[Mainer]

Racking off might have been a little early, and may have caused the yeast to slow. What's your fermentation temp? Do you have the ability to raise the temperature a few degrees? It might help the yeast get you to terminal gravity.

 

[henchman24]

I never really have issues with 644 being slow. I usually hit FG between 4-6 days. I usually get a bit more than 85% attenuation too. What temp are you fermenting at?

 

[Elixer]

Yes I have temperature controlled fridge for fermenting my beers.

I started at 65F and heated to 72F over the course of 5 days. Never changed it since then. I'm afraid of letting it go warmer, because of the the dry hops. Perhaps a few degrees won't matter after all.

I'm currently at close to 78% attenuation. If it would reach 80% depends on the grain bill and applied mash schedule. Since this is my first time brewing this recipe, I have no way of knowing where it should take it.

Would warming it by a few degrees harm the sought after hop flavors?

 

[henchman24]

When I make a NEIPA with this yeast. I typically start at 70-72, keep it there for a whole day, and then ramp to 78 by the end of the first week when I keg it. That is where I personally like the yeast the best. 65 seems pretty low to me for this yeast to start. Right now the flavor profile is set, so a few more degrees wouldn't really hurt anything, and will help it finish. At 78% it might be done though.

The way I understand it (and I could be wrong), temperature is mostly about how quickly the hop oils are absorbed. I only do 3 day dry hops and try to rush these IPAs. The longer an IPA sits, the more the hop flavor is lost. So I take the path of fermenting quick, short dry hops, and quick packaging. With this yeast, that means low 70s to start and high 70s to finish and I can be ready to package after 7-8 days.

 

[Elixer]

Thanks, great information. I ramped it up to 78F and keep it there for two or three days. We'll see where it gets me.

I thought that this strain would cope well with the colder temperatures. Lessens learned​. Nevertheless the beer tasted great, so I'll definitely be using WLP644 again at higher temperatures. Perhaps making even tastier beer

 

[filthyastronaut]

I bottled today, gravity reading was 1.012. Tasted amazing, maybe a hint of sweetness, but not much. With 85 percent attenuation it would be 1.008, so I primed for 2.0 volumes instead of my usual 2.4. My last IPA had this yeast along with Conan and London Ale III, and it was carbed and tasted perfect after 9 days in the bottle, so I'll try it in a week or so.

 

[Elixer]

How long did it take from brew day to bottle?

When I checked the airlock activity yesterday it had slowed down to a rate of once per 16 seconds. A few degrees higher seems to help the yeast finishing fermentation. I hope to bottle tomorrow or the day after.

 

[filthyastronaut]

How long did it take from brew day to bottle?

When I checked the airlock activity yesterday it had slowed down to a rate of once per 16 seconds. A few degrees higher seems to help the yeast finishing fermentation. I hope to bottle tomorrow or the day after.

Exactly two weeks. Same as practically any fermentation I do. I would have let it sit longer but the fermentation was so vigorous and krausen dropped quickly enough that I bottled it early against my better judgement.

Also, I'm gonna pitch a good amount of slurry into a Belgian Single recipe today, and probably ferment starting at 75 this time. I can let you know how that goes as well.

 

[Elixer]

Did you cold crash your beer before bottling? Normally I would do a cold crash, but I'm not sure if this beer would benefit from it. It will probably be long gone before autolysis kicks in.

 

[filthyastronaut]

Did you cold crash your beer before bottling? Normally I would do a cold crash, but I'm not sure if this beer would benefit from it. It will probably be long gone before autolysis kicks in.

Nope. It was dirty as hell, probably the least-floccing yeast I've ever encountered. No worries though, cold conditioning in the bottle will do it even though it will require some pouring skill.

 

[filthyastronaut]

Tasting a bottle right now, did not overcarb in the slightest. It's really good. So that's success with a two week fermentation. Temperature probably made a big difference.

 

[Elixer]

I bottled the 14th of May. SG was 1.010 by then. 85% attenuation. Because the fermentation took forever I was slightly concerned about the yeast being not entirely finished, so I aimed for 1,8 volumes of CO2. On the low and safe side.

1,5 weeks later the carbonation was perfect, so I stored the bottles a bit colder. Carbonation has not increased since then. I should mention that I think that the yeast fermented a bit more than only the bottling sugar, so keeping the amount of sugar low was a good thing. Otherwise it would have become too spritzy.


The beer pours hazy. Color is almost orange. It smells and tastes awesome. Best beer I've ever made. Silky smooth and very fruity. Citra, Mandarina and Nelson are working great together in equal parts. No tropical fruits, but a lot of citrus.

View attachment 1495865299206.jpg

 

[filthyastronaut]

I also just bottled my blonde with this yeast! 2 week fermentation, pitched at 75 and let free rise. Went down to 1.006 which is exactly 85% attenuation. Tastes . . . clean. A hint of American hops from the unwashed IPA yeast, and grainy sweetness. The temperature probably had something to do with it, but it could also be the higher pitch rate.

 

[Sechelter]

I've used this yeast twice, once for a blonde and once for a dry-hopped sour. Really, really slow secondary both times. With the sour (3.5 pH), the primary ended after about 5 days but now its been 4 weeks and the gravity (now 1.006) is still dropping and the air lock bubbles about every 40 seconds. I've been holding a steady 80 F since mid-way thru the primary. This was pitched w/ a 1.5 l starter built from a fairly fresh package. My experience is that this is a slow, brett-like fermenter, especially in secondary with the complex sugars.