I have a saison fermenting at 90 right with 3724 after reading a thread in here about wyeast’s 90 recc
It’s my first saison, so fingers are crossed!
My understanding is that this isn’t WY vs WLP but both WLP. It is said that 565 is supposed to be the same isolate as WY’s from Dupont’s 4 strains (a straight culture from Dupont is supposed to contain 4 different strains), and the WLP566 is supposed to be an isolate of a second strain from Dupont (one of the other 3 they didn’t isolate for 565). Mike Tonsmeire made note of this in his recent blog post on American Saisons.
Great blog post. I love his stuff.
I’ve had very good results with 565. I think I’ve only had one occasion where the yeast slowed down and required some manipulation, but otherwise it has performed very well especially in the attenuation department.
Currently, I have a blend of 566 and 568 going, where I’ll also add some Brett C after three days of active fermentation. This is the first time blending them together so it should be interesting. I’m also going to add some oak chips for a week or so.
Love the Belgian Saison style. 
Y’all know, I’ve done a ton of Saisons right?
I’ve also never had problems getting any of the Dupont derivatives to ferment out completely.
I’ve written this before but it bears repeating:
- Use a very healthy starter - no underpitching
- Start cool - 63-64F and allow to ramp naturally
- No airlocks/blow offs. Use foil. The Dupont strains in particular are backpressure sensitive.
I’ve never had a problem or “stall” with Dupont either. I follow the same pitching/temp profile as Drew.
Though I use an airlock. Always. 8)
Scientifically it is impossible for much pressure differential with airlocks or blowoffs, unless they get clogged. Is that your fear, Drew? Clogging from yeast blowout? Otherwise, assuming no clogging, the pressure inside the fermenter is atmospheric, plus a teeny tiny insignificant amount that causes the bubbling through the airlock.
In my experience that ‘insignificant’ amount can make a lot of difference in ester production. Though I don’t have much experience with playing around with it with saison yeast… I have done many experiements with English yeast and no airlock for sure gives me a fruiter ester profile.
if something works, keep doing it. I think most people understand this.
Personally I’m just not afraid of 0.036psi (0.2% above ambient) from a 1" column of water in my airlock.
I have had good luck getting 565 to finish with a low FG. It may stall for a week, then resumes fermentation like nothing happened. The author in the article may not have the time to wait it out in a commercial brewery. A solution would be a mixed fermentation to turn the tank in a timely fashion.
I think it may be about the CO2 O2 exchange in open fermentation, not the small pressure from an airlock.
Edit - it might be a REF project?
Never heard that. Thanks Drew !
No fear, just a combination of practical experimentation and information directly from WL’s and Wyeast that those core Saison strains are back pressure sensitive, not unlike a wine yeast which is as well.
0.036 psi, eh…
sorry if that was too Full Enginerd for present company.
I didn’t calculate it; I’ve just memorized the number from scores of top pressure discussions my friend (who did calculate it) and I have had with internet denizens over many years.
I’ll reiterate: If something works, keep doing it. I’ve had at least a couple of Drew’s saisons and they are excellent.
I’m not sure much o2 gets into a fermenter with an empty airlock on it (just to keep dust out) or even if it were a carboy with foil over it… During fermentation there is an awful lot of co2 shooting out of there… I don’t really know the answer though… I just know from my experiments my English beers turn out much better if I have as little pressure as possible during the fermentation. (I have done it in the boil kettle with the lid just sitting on it as well) Conversely I often do a 15psi ferment for beers I want to come out cleaner which I find also makes a difference… Though obviously 15psi is quit a bit more pressure difference than airlock vs no air lock 
I was thinking about open, no lid in a clean environment, vs. closed with airlock.
German wheat beer yeasts are said to benefit from open fermentation. Sierra Nevada and New Glarus use open fermenters for that type of yeast.
German lager breweries in Franconia use open fermenters also.
The wheat beers in Germany are in round fermenters with a trough to harvest yeast. Go down about 1/3 way to see one at Schneider in Germany. Lots of other good pictures.
http://brewingjourney.blogspot.com/2011_04_01_archive.html
Yeah I would do totally open fermentation like that… if it were in my ability So I have to do “open” fermentation with something covering the fermenter but not sealing it. It’s the best I can do on the homebrew scale. I’ve done many side by sides with my English beers and I always prefer the open fermentation batch. Have not tried it with German ones… Wonder what the benefit would be. With the English strains I do it mostly to encourage esters.
Brewing TV did an open vs closed experiment way back when they first started. Used the WY hefe yeast, IIRC.