07/03/08 06:35 PM
Wild saccharomyces fermentations, and flavor
The point of this regrettably long thread is to solicit results from experiments of a similar nature, or opinions of any kind.
Abstract: I pitched a bunch of wild yeasts and bacteria, fermented them at high temperatures (while intentionally attempting to minimize lactobacillus, and ended up with a completely neutral, "1056-" tasting beer; am surprised.
About a month ago I brewed a beer with wild yeasts isolated from a sourdough starter. I collected the starter during a warm summer week about four years ago, and have been using it to make bread ever since; the resulting bread can range in flavor from "pretty damn sour" to "are you sure this isn't straight Fleischmann's quick-rise?" If I let it go for a long time at warm ambient temps it is nice and sour, while shorter risings in cooler temperatures have a very mild flavor, to the point of having no lactic character at all.
The beer I made was very low gravity -- 1.030, in order to increase hop utilization and suppress lactobacillus.
A year ago, I made a sour beer with this same culture. Starting with a pLambic turbid mash with very light hopping, and a single night in the koelschip, I pitched some of the starter into a carboy, left it open (well, "sealed" it with a wad of paper in the opening, to keep the fruit flies out). one year later, this beer has a very thick pellicle and the flavor seems to have stabilized; it is fairly acidic with a strong lactic character and zero acetic (and for me, zero acetic is a good thing, particularly for beers from open fermenters).
So I could not imagine that last month's beer would not turn out acidic, and wanted to test high hop rates and reduction of lactobacillus activity -- this time, I wanted to try to obtain a non-sour beer from the same yeast. I hopped the hell out of a low-gravity wort (1.030 as state above, with 5 ounces of cascades in a two-hour boil). I then pitched some of the starter, and had a nice looking (closed, this time) fermentation going in short order. The yeast was a total top-cropper, with small greenish-brown floating colonies once the kraeuzen died down. The little yeast colonies looked exactly like what I get out of the Wyeast Whitbread (1099?) Fermentation took place for one month at 70 to 90 degrees, although within six days gravity was down to less than 1.010.
So, I kegged the stuff today. I was expecting a beer with considerable wild flavors, from the combination of all-wild yeasts, possible residual lactobacillus, high temps, etc.
And what did I get? Basically a very neutral-tasting "ordinary bitter!" It is pretty bitter, obviously, from all of the hops, but I really can't detect any yeast-based flavor contribution, esters, etc.
I might as well have pitched a Wye-te Labs Ballantine monoculture.
At the very least I expected a strong-tasting "Belgian" profile (like, say, what one gets out of Dupont or Blaugies yeasts at summery temps -- you can't call that neutral!).
And I would love to hear what anyone else has gotten from wild saccharomyces experiments.
07/04/08 02:47 PM
Re: Wild saccharomyces fermentations, and flavor
Yes, that is what I meant -- I was expecting a blow-out in weird flavor from the small beer, and got neutral tasting stuff.
And CDH -- that is very, very possible. And also possible that the high bitterness is masking some more subtle flavors/esters from the yeast. Either way, I should run it by some others.
Mike -- the Kvass sounds tasty.