Wild yeast capture one more time

A while back I had a go at capturing some wild yeast. I had one promising jar out of four but whatever was in there wasn't able to attenuate the wort beyond 1.020 and it got dumped. I'm still pretty much in love with the idea of capturing some wild yeast and brewing with it, either lambic style or isolating and using a single strain. I've started growing some samples of my sourdough starter and kombucha on plates and I'm looking forward to seeing what will come of them.

Anyway, I had a little bit of left over malt extract agar when I made up the plates yesterday so I put some paper towel over it and left it outside overnight next to our hop plant. I brought it in again in the morning and it'll sit at room temperature for a week or two and we'll see what it does. Since it's a jelly, whatever grows on there will be on the surface and in theory, I'll be able to pick out the promising colonies.

Wild yeast update #2

It's been about six weeks since I collected the wild yeast. Two of the jars grew mould and were chucked. The other two were promising and they were stepped up into 250 ml erlenmeyer flasks.

The most promising one is now in a 2l erlenmeyer flask, growing and getting ready to do its thing in a batch of beer. I tasted it and when I failed to die my mate Luke sampled it too.

Jar #3 was the wild yeast winner

I'm finding it really hard to describe. The dominant citrus character has given way to something else. Earthy is the word that comes to mind but that's one of those nothing descriptions that I use when I can't really get any closer to the reality. It doesn't smell anything like dirt. Spicy or herbal are descriptors that nibble around the edges of the aroma but don't really get at the heart of it. I don't know. Maybe a menthol kind of flavour going on? Strange. That's all I've got. It's definitely turning into something else and I guess I'll have to wait and see how it turns out.

One thing I was a bit concerned about was how well it would attenuate. It seemed to have done a pretty good job of dealing with the malt extract though. Not really dry, there was some slight residual sweetness but it seemed to have a pretty average attenuation, somewhere in between an English Ale and a dry IPA.

Can't wait to try this Tassie wild yeast in a beer

I'm thinking of using it in something relatively low alcohol and simple for its first run. Something like a Wit maybe. Not sure.

The other one, from jar #4, got tipped. It was starting to grow some mould and I wasn't willing to try and salvage it.

Sourdough

It's not quite beer related but it is made using wild yeast.

Now smelling like grapefruit

Wild yeast update

A few days in and I've got activity in all four jars. Jars 1 and 2 look like they've just got mould but I'll let them go a bit further and see if they do anything else.

Jar 3 has a few patches of bubbles on its surface. I presume that's CO2 from some captured yeast but that's a total guess. It's obviously doing something. It has a nice, tart, lemony smell. I have hopes for this one.

Jar 4 is crazy, it developed clusters of tiny bubbles on its surface and then within a day the whole surface became covered in... stuff.  It looks like there's at least two different bugs at work here. The aroma is very similar to jar 3 but a little less fruity and tart. But there's this wispy network that covers the surface. I don't know what's going on there but it looks pretty nasty. I guess I'll have to wait for a few weeks and see what it produces.

I transferred jars 3 and 4 into a couple of erlenmeyer flasks with a bit of extra wort I cooked up. I'll let them go for a few weeks and see what we have.

Capturing wild yeast

I've been really keen to try and capture some wild yeast to use in a brew since I read about it in a homebrew forum a couple of years ago. It's a romantic idea, capturing the essence of Tasmania in a beer and creating something truly unique. A Tasmanian Lambic.

The main characters at work in a sour beer are the yeasts saccharomyces and brettanomyces, and the bacteria lactobacillus and pediococcus. These are pretty much everywhere so the plan is to capture some of these wild bugs from around my place and see what kind of character they give a beer. I used 4 jars to maximise the chance of success. If more than one works out then I'll mix them together and see what happens.

I cooked up 500ml of water with 50g of dried malt extract and divided it 4 ways. I covered the jars that are going outside with some cloth to keep any marauding insects and other debris out of the starters.

Jar 1 has a few grapes from our vine. Hard to see them but they're in there.

Jar 2 on the deck

Jar 3 on the disintegrating seat

Jar 4 under a very late fruiting peach tree

I've left jars 2-4 outside overnight and I'll collect them tomorrow morning. Jar 1 is on top of the fridge and hopefully some brettanomyces yeast from the grapes is already going to town on the grape/wort stew.

It's a longish term project. These starters might be duds and even if they're all good, I don't expect to have a finished beer in less than 8 months and possibly quite a bit longer. I'll brew a simple recipe and seeing how the bugs go with it. If it turns out well, I'll save the yeast and use it again.