|This years sources of wild yeast, waiting for wort.
L->R: Clover, Chokecherries, Raspberry, Tomato, Blueberry, Young hop (goldings)
I’ve been doing a bad job keeping my hunting wild yeast project up to date. The brief re-cap would be that I captured and characterized a series of wild yeast I purified off of some Pilsner malt. The first results were not satisfying, but I kept the ferment going and continued to collect yeast over a period of 6 months. To summarize the results of the over 80 strains I captured and tested – they all sucked. Only half attenuated worth a damn, and those which attenuated left beer that tasted either oxidized, phenolic to the point of being undrinkable (burnt plastics and dirty socks abounded), or both.
While the first hunt didn’t turn out as well as I had hoped, it did serve to get a lot of groundwork established. I now have a tried and tested method of identifying yeasts using DNA sequencing (posts 1, 2, 3 and 4), as well as my purification methods down pat…so its time for the 2014 hunt!
This years strategy is a little different. I’m stealing some wort from my Ephemeral Cranberry Wit, and am inoculating it using various yeast sources from around the yard. My wife runs one hell of a garden, and form there I’m taking yeast from some raspberries, blueberries, tomatoes, and strawberries. In addition, we’ve got some hops, choke-cherries and wild clover growing in the back, so I’m going to harvest from those as well. Each fruit/veg (OK, technically they’re all fruits but the clover & hops – which are neither fruit nor veg) will be dropped into ~25ml of freshly brewed wort and allowed to ferment out for at least a month.
After the month is up I’ll do my first harvest of yeast, plate them out, and see what I find. Every month or so thereafter I’ll repeat the harvest. Interesting yeast will be kept frozen and eventually subjected to fermentation tests to see how well they work, and how well they taste. I’m also going to harvest the end-product of the ferments (at about 6 months) as mixed cultures, potentially for use in some sour beers down the road.
I’ll add more posts as we go, but to finish here’s some semi-artsy shots of the yeast sources.