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.