Capturing wild yeast question

[Will Smith]

So I'm trying to make my first wild fermented beer and have a couple of questions about yeast capturing. I've read a couple of threads but still don't have the answer i need.

My plan is to place wort in a sanitise jar, lid off, outside for until i see some activity.

My questions:
1) Is it best to leave it completely uncovered? Or with a cheese cloth or something covering it to stop bugs getting in?

2) Is it best to leave outside, inside or next to a window that is open in the day and closed at night?

Thanks a lot!

 

[cactusgarrett]

I needed a few stabs at this to get it right. The main hurdle I had to overcome was the issue of a jar of wort being too "little" volume. It cooled too fast and allowed the harboring of other things besides wild yeast. I did everything suggested - hopping, pre-acidifying the wort, etc., and it didn't work. I then cheated a bit by dunking various pieces of my backyard in the wort (a flower, for example), which worked. Ultimately I dove head first in to do a full 5gal batch and let it cool overnight to capture something - which worked like gangbusters.

You should only need to leave it out overnight, and just because you don't see activity, doesn't mean you didn't capture anything. It should take anywhere from two to seven days for the wild yeast to "take" and start a ferment.

That said, every time i've done it, i've covered the vessel (brew kettle, jar) with cheesecloth to keep the bugs and floating debris out. As to where you leave it, that totally depends. If you leave it inside, you're most likely to catch what you've got floating around, say, your brewhouse. Outside is more likely to catch wild yeast itself. Reading/listening to various resources, it seems the best areas are near orchards/fruit yards, but basically it was suggested "follow the leaves". If you find offal around the ground from trees, those have been found to produce the best wild yeast for brewing.

You could also cut the middle man and just dunk various pieces in wort - fruit from trees, bees, etc. Check out episode #005 of the Milk the Funk podcast for all thing Bioprospecting. Good stuff there.

 

[enkamania]

1. I covered the jar with a hop sack. Some people get yeast from insects, so your choice.
2. I put them outside. My latest I cut some flowers from a cherry tree and threw in the wort.

I have done it as little as five hours. It takes the wild yeast longer to show signs. Also important, lower the ph of the wort below 4.5. I just tasted the hydrometer sample of my first wild yeast beer and it's great.

 

[RPh_Guy]

I generally put stuff like flowers, leaves, bark, or fruit in acidified lightly hopped starter wort to capture the yeast rather than leaving it outside. ... These have all started fermenting within around 24 hours. It's tempting to open them because sometimes they smell really good, but the trick in my experience is leaving them closed/anaerobic so they don't grow mold.