Advice needed - stuck fermentation in BIG saison

[txtaquito]

Made a bigger than anticipated saison with an OG of 1.100 (target was 1.094). So I made a 1L starter 24 hrs in advance. Ive never had problems with 1L starters in big beers - even stouts at 1.160. Pitched at 65F (those plate chillers are killer fast in the winter) and set my chamber to ferment at 72F. Next morning there was activity but I observed that the internal temp of the fermenter was at 82F so I killed the warmer, opened the chamber and allowed to slowly fall to ambient ~71F. I woke this morning to no airlock activity and internal temp of ~75F. Current gravity read is 1.050 and expected is 1.029. Is it stuck? Need I pitch again with another starter or high attenuation strain or let it sit for a week?

11 lb United Kingdom - Maris Otter Pale
4.75 lb American - White Wheat
0.75 lb Flaked Wheat
1 lb German - Melanoidin
1 lb Lactose (Milk Sugar)
8 lb Ube Purple Yam
2 oz Pacific Jade
White Labs - Belgian Style Saison Blend WLP568

Thanks,
Tex

 

[Dirt_McGirt]

My guess would be that the yeast is probably just working slower due to the 1L starter and stressed because of the early ramp up and temp swings, generally. It's been 2 days? Probably still fermenting - give it time.

As an aside, that's a pretty out there grain bill for a saison. Do the yams turn it pink? Hope it winds up tasty for ya.

 

[txtaquito]

Yea it was a pretty out there grain bill. I made a similar one 4 weeks ago with half the yams and 2row rather than maris otter. It was forking delicious but I wanted more cowbell, I mean yam taste, so I upped the yam bill, added the melanoidin primarily for color boost to the yam. Yes, the yams made it pink. Target OG wasnt too far off from the OG of the last session I brewed of the same beer and it came out great! I did also observe, todays gravity sample yielded more of a funk flavor than last batch. Likely because its stressed. Im going to grab a vial of the same yeast anyway and begin a starter and wait. If I dont need it, I can preserve the starter for next batch in two weeks.
Thanks for your input

Cheers ~

 

[passedpawn]

Wyeast 3711 will fix what ales ya. Just pitch and stand back.

Why the lactose? At 1.100, you were already expecting a big FG. Lactose would just make that much worse.

Did you add the yams to the mash? They are probably all starch, you'd need to convert the starches to simpler sugars before the yeast can do something with them. Are there enough enzymes from the barley to convert all those yams? Not sure what temperature the potato starches solubulize, but mash temps might not do it. I'm really in the dark on the yams

 

[txtaquito]

@passedpawn:

I didnt think about the lactose and FG equation vs mouth feel so thanks for that but I also didnt shoot for such a high OG. It was in my last variation of this recipe so Im just tweaking ATM.
As for the yams, no I mashed them as a separate mash. I made "mashed potatoes" with them, step mashed from 125F to 160F over 45 minutes adding in alpha amylase in the last 30 minutes to help convert those starches, mashed out at 170, allowed to cool to 168F and used as the major portion of my mash water for the main recipe, topping off with regular water from my HLT to reach my total mash volume. I think it was a brilliant idea, actually Oh, and yams/potatoes gelatinize at much lower temps than grains, starting around 120F but a step mash is very helpful to convert those into simpler sugars. Since theres not any literature out there that I could find on just yams/sweet potatoes/potatoes, I had to basically guess the process. Had my tun been large enough to handle that grain bill PLUS 8 lbs yams, I would have never thought about mashing separately!

 

[txtaquito]

I appreciate eveyone's feed back! So after reading so many ways besides the feed back here what I decided to do was two things:
1) I will try and "coax" the yeast into eating again by adding less than 300ml solution of corn sugar water. I dont want to give them much because they will love the simple sugars and when its gone they may ignore the more complex sugars and fall right back down again. I also gave the bucket one quick but vigorous shake to stir them back up.
2) If / when this doesnt help, Ive started up another 1.5L starter (and even that is still a little small) with the same yeast.

If these fail I may give in and go with a high attenuation strain starter and hope that the initial fermentation I got in the beginning gave the esters and flavors I was looking for so that the new strain wont change the flavor profile much.

Cheers ~

 

[Buc_Nasty]

Not enough yeast, 1 vial and 1 liter starter is nowhere near enough yeast for a beer that big. I know I'm not helping by saying that, but for future beers you should use a yeast pitching calculator. If you do option 2, for best results pitch it at high kraussen.

 

[txtaquito]

@Buc_Nasty - you are quite right! I realized I under pitched but really was looking for help on getting it un-stuck Looking at the calculator, that brew needed a 4L starter! I guess I really didnt understand how to use the calculator but Ive never had problems with a 1L starter even on brews bigger than this one so I just pitched what I always pitch. It appears to be going once again. Ive seen airlock activity over the past 5 hours and nudged the heat a little to 78 to coax the poor stressed lil guys. Looks like this one will need at least another week and even then Im sure they are screaming weird esters right now so I need to let it diacetyl rest for several days after and hope they clean up those flavors.

Cheers ~

 

[Queequeg]

If it still stuck pitch 3711 at high krausen and it will burn through the remaining sugars