Friday, March 9, 2012

The Beast from the Yeast

Those of you who follow us on Facebook (what, not you? Shame on you...) may have heard about a little wild yeast experiment we're currently working on. While the planning for the brewery is going well and finally moving forward after a few months of arduous location scouting (we'll have another blog post with details on this one very soon), we've been working on harvesting some wild yeast from our hometown of Saxapahaw, NC, as both a nod to our Belgian brethren across the pond and an exploration of just how "local" we can attempt to create a beer recipe.

A little birds-eye perspective on where we placed each of our collectors.

Our experiment began a few weeks ago by creating 3000mL of "starter wort" using carbon-filtered water and several ounces of light DME (that's basically a sugar water made from dried malt powder and a little yeast nutrient thrown in for good measure). We acquired a few small Pyrex containers and removed the center of the plastic lid with a utility knife, so we could "seal" the container but leave a nice big hole in the top to let the bugs in. We then sanitized the containers along with some cheesecloth and assembled each of our "yeast traps" by adding the wort, placing the cheesecloth across the top, then sealing the whole thing with the lid, leaving a nice, big, open hole in each for the yeast (and other things) to come on through. With the containers filled and prepared, we ventured out to a few spots in Saxapahaw to see what we could harvest.

The fig tree atop the hill
where Saturdays in Saxapahaw
is held each summer.
Sample A was placed beneath the fig tree that sits atop the hill overlooking the spot where Saxapahaw hosts its Saturdays in Saxapahaw events each summer (if you haven't been to one, you're missing out — follow SXPHW on Facebook for the upcoming schedule, which always includes really great bands every weekend). It's a little early for the tree to bear fruit, of course, but we wanted to see if some of the yeast might live there in the "off season", as it were.

The fireplace just off the Haw River,
south of the Rivermill apartments.
Sample B was brought in from a small perch on a stone wall just off the bank of the Haw River, which runs directly through Saxapahaw on its way down to Jordan Lake (then the Cape Fear River, then the Atlantic Ocean). Our hope with this one was to find out if the flow of the river might bring interesting things from the west, where it starts all the way from around Kernersville, NC. (Incidentally, when we picked this one up after a couple days' exposure, it looked like some wild critter — a raccoon perhaps? — had tried to get at the sweet wort inside. Luckily, the cheesecloth held fast and the varmint was deterred).

On the stone wall that surrounds
the patio upstairs at the Rivermill.
Sample C was placed just a bit closer to home, on the wall that surrounds the patio just outside the door of our apartment. We figured this was a nice, central location that would provide pretty reliable exposure from a number of different sources from all over Saxapahaw. Plus it was easier to keep an eye on it.

And Sample D we decided to actually leave inside our apartment, on the windowsill, just to find out if the "funk" might differ between inside and outside. Didn't have much hope for this one, but when we collected it after a few days, we were pleasantly surprised with a tart, floral, bready aroma.

After a few days of leaving our containers out in the cool, dry weather, we collected our samples, brought them inside, then transferred each of them into their own sanitized glass container (removing any mold that had gained purchase on the surface so as to try to cut down on too many off flavors or harmful bacteria from the start). Each container was covered with sanitized aluminum foil, so there'd be a bit of oxygen transfer to allow any yeast to grow a bit longer, then left alone to settle out.

After a few more days at room temperature, we made another "starter batch" of our DME-wort (twice as much this time), then pitched each wild yeast starter into sanitized half-gallon growlers with air-locks, like you see in the photo below.

Our wild yeast samples, safe and sound back at the homestead.
It's been a few weeks as of the time of this post, and so far, we've got fantastic growth in our "Fig Tree" sample and moderate growth in the Windowsill container (strangely enough). None of the samples have much of an off-aroma (none of them can safely be tasted just yet, just in case anything dangerous is present, which should be killed over the next few weeks as the pH drops in the samples), with the River and Windowsill samples smelling the cleanest (a varying degree of lemony, tart, spiceiness in each) so far. As things progress, we'll document in more detail the difference between each, and what we notice in the appearance, aroma and (eventually) taste of each sample.

Keep an eye on our Facebook page and this blog for a follow-up post over the next few weeks, spotlighting what we discover when we get these beasties grown up a bit more and under a microscope! Assuming we can get viable yeast from one (or all!) of our samples, we're planning to brew something rather special to be placed in a very cool 10g cask we picked up from one of our favorite beer bars in Raleigh a few weeks ago. Stay tuned, wild beer fans!

Postscript: In case you're wondering, the little note on each container says "Please don't drink me, disturb me or throw me away. I'm a yeast experiment left by someone who lives in the Rivermill Apartments. Thanks!"

No comments:

Post a Comment