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Tuesday, August 18, 2009

Dupont Yeast: Early Discoveries

Yeasts are funny little buggers. They have radically different preferences and behaviors. Ultimately, they all nosh on sugars and excrete alcohol, but the ways in which they do this is a wonder to behold. Case in point: the yeast of Brasserie Dupont, makers of saisons. Beginning last week, I began cultivating the dregs from a bottle and simultaneously picked up a batch of Wyeast's version (just to be safe). I brewed my wee saison (1.035 OG), aka "petit saison" aka "grisette" yesterday and got a chance to see the yeast in action. Just to be safe (again) I decided to pitch both yeasts, which by 3pm amounted to a substantial quantity. Still, not substantial enough to account for what came next.

Dupont's yeast is famous for a number of reasons. The brewery ferments its beer at between 85 and 95 degrees fahrenheit--a shocking fact, given that most breweries keep their beer cool (at least 20 degrees colder for similar ale strains) so it will be smooth and clean. And then, famously, the yeast craps out on you. It races along in sweaty fury until the beer is mostly ready, and then activity screeches to a near halt. You have to be patient and let it finish out--and it will finish out, with attenuation rates above 90% (another amazing fact). One theory holds that the strain was originally a wine yeast, but this may be an apocryphal story added later by homebrewers who had to come up with a rationalization about why the heat didn't ruin their beer, why it could still be called yeast and not pack off the women and children in the night.

Still, what unfolded was astonishing to behold. Within four hours I had a heaving two-inches of foam. Yes, heaving--the damn thing looked like it was breathing. I had swaddled my 85-degree beer in a flannel shirt and taken it upstairs, where the house is the warmest, but I didn't expect such vigor so early. I was sort of glad it was a smaller beer, but even still, at 5 am I was up examining it, just to make sure it hadn't gone walkabout on me. A yeast like that, you never know.


  1. I had the same experience with my saison this year. Granted mine was a much higher OG (1.064) it did crap out after 2 days to almost no activity and a gravity reading of 1.04. I let it sit for two weeks (in the mid to high 80s, I brewed during the heat wave) with little more action from the saison yeast, so I pitched a packet of dry coopers to get it done. 4 days later I had a FG of 1.007. It is bottle conditioning as we speak. I think it turned out allright, but I'm not so sure I'll brew another saison for a while.

  2. I used some of the White Labs Saison II (WLP566: not sure who's strain) yeast before with similar results. It just crapped out about around 70-75% ADF. I cranked up the temp and got it to drop a few more points. Added some other yeast as well, just couldn't get it dry enough. Still tasty, but not dry enough. I was going to try the Dupont from the bottle next time I do a saison.

    You want a yeast to blow out your fermenter, try the WLP300 Hefe. Man, that stuff blows out my airlock every time I use it.

  3. Ralph - My guess is that is the same strain as the Wyeast 3068, which does the same thing. I brew a 5 gallon batch in a 6.5 gallon carboy and regularly get blow off.

  4. Two words for you felines.....FERM CAP...say good bye to huge blow offs and boils over. Started using it recently in both the boil and primary.

    As far this yeasts goes I have a smack pack but wouldn't you know that we installed central air this year and so I no longer have ass sweat temps in my house. I am thinking of doing it in the garage and just let it go however I worry about temps at night. Maybe I can rig heating pad on it to work at night or something.


  5. Dupont-gist zou werken aan temperaturen rond 90°F (+-30°C), niet 90°C dus...