Am I wild or crazy?

[Dale Owen]

I saw this video where these fellas fermented a beer with a log. So, I'm a total yeast guy when it comes to brewing and I check it out. That seemed interesting enough, but looking around on the interweb I came across information on wild yeast on certain fruits and then I came across kveik and, of course, researching kveik pointed me to raw, or unboiled ale. I can't help how fascinated I am with all of that.

Obviously I have more questions than answers, but I think at some point I want to brew a farmhouse raw ale. Instead of a kveik yeast, which looks fairly complicated to actually get ahold of, at least what is considered legitimate strains, I'm thinking of harvesting wild yeast from my back yard.

I saw where the the film on certain fruits are actually yeast. I have these trees in my yard. I'm not sure if they are miniature apples or crab apples. Anyway, I have always noted a film on them. I don't ever spray any insecticide or fungicides. I'm thinking, now, that is probably wild yeast.

The evil plan I'm formulating is, sometime late summer or early fall, I'll grab a few of those apples and toss them in some wort and see if I capture a wild yeast. Then, I'll brew something that incorporates the apples and brew a raw ale.

Thoughts? Am I crazy, or just mad?

 

[RPh_Guy]

I saw where the the film on certain fruits are actually yeast.

You can get wild yeast from pretty much anything outside because microbes float around in the air. I've captured wild cultures from leaves, bark, fruit, and vegetables.
Your crabapples will absolutely provide you with a wild yeast culture.

Most wild cultures do not attenuate wort very well, only around 50% apparent attenuation. They're probably struggling to ferment maltotriose (and dextrins).
I haven't yet found any strains/cultures that are great for beer. ... However there's nothing crazy about trying.
You should consider pre-acidfying the wort to pH 4.0-4.5.

On the other hand I've made a number of ciders with wild cultures and they've been excellent.

 

[cactusgarrett]

kveik yeast, which looks fairly complicated to actually get ahold of

It's actually very easy. There are a number of people sharing their banked cultures, and most of the big labs sells their isolates of kveik.

 

[bracconiere]

Thoughts? Am I crazy, or just mad?

i would say adventurous ...(but really, as far as i know, just put your fermenter with the lid off next to an open window?)

 

[RPh_Guy]

It's actually very easy. There are a number of people sharing their banked cultures, and most of the big labs sells their isolates of kveik.

It is more difficult to get original mixed cultures vs isolates.

 

[Dale Owen]

On the other hand I've made a number of ciders with wild cultures and they've been excellent.

I've never made a cider yet. But these crab apples I have are actually pretty tasty. Maybe this is the year I learn to make cider.

Regarding the attenuation. Would that mostly be a concern for what ABV is achieved? I don't like to brew imperials, but I do like to hit 6-7 ABV. Would coming up with a grain recipe that has a higher OG address that, or would that just over tax the yeast altogether? I'm sure that will all depend on whatever yeast I capture.

 

[TwistedGray]

@Dale Owen - As @RPh_Guy noted, the wild yeast on that apples won't attenuate significantly; however, I find that to be a good thing. Using the apples from my tree, I juice them, pour the juice in a fermenter, add an airlock, and let the wild bugs do their things. That leaves me with a sweet, 3ish% hard cider with almost no effort...it's great : )

 

[Dale Owen]

It's actually very easy. There are a number of people sharing their banked cultures, and most of the big labs sells their isolates of kveik.

I still have a bit of research on kveik. From what I read so far, commercial labs have yeasts that they label as kveik, and some argue they are not true kveik. I found a link a kveik registry, but haven't had time to figure out the ins an outs of obtaining kveik. But, its a fascinating subject.

http://www.garshol.priv.no/download/farmhouse/kveik.html

 

[RPh_Guy]

Regarding the attenuation. Would that mostly be a concern for what ABV is achieved? I don't like to brew imperials, but I do like to hit 6-7 ABV. Would coming up with a grain recipe that has a higher OG address that, or would that just over tax the yeast altogether? I'm sure that will all depend on whatever yeast I capture.

Under-attenuated beer may be too sweet, and indeed the ABV will be lower for a given amount of grain.

@Dale Owen - As @RPh_Guy noted, the wild yeast on that apples won't attenuate significantly; however, I find that to be a good thing. Using the apples from my tree, I juice them, pour the juice in a fermenter, add an airlock, and let the wild bugs do their things. That leaves me with a sweet, 3ish% hard cider with almost no effort...it's great : )

They do attenuate "significantly" in my experience. In lightly-hopped DME 100g/L starter wort (OG approx 1.037) my FGs ranged from 1.006 to 1.022 (median 1.017) in the 7 wild captures I've tried so far.

My point was that these apparent attenuations are typically less that what would be expected from commercial beer yeast.

My ciders with wild yeast always attenuate fully. Not sure what weak-ass yeast you have over by you.

 

[TwistedGray]

My ciders with wild yeast always attenuate fully. Not sure what weak-ass yeast you have over by you.

It's that California yeast : )

Actually I haven't bothered to take an FG reading, so I don't know where this one sits (different apples and different juicer...should have regular supply of apples going forward now). It's been aging in the carboy for the last few months because I've been to lazy to package and still have about 15-20 ciders waiting to be drunk.

 

[Dale Owen]

Under-attenuated beer may be too sweet, and indeed the ABV will be lower for a given amount of grain.

Not sure if its something that's done, but would a 2nd pitch after a few days in the primary help, hurt, or have no effect?

 

[RPh_Guy]

The more variety of wild microbes you put in the beer/wort, the more likely it will attenuate higher. Pitching the exact same microbe(s) again will generally have no effect though.