Using yeast from blow-off tube

[JAReeves]

I was looking for an answer to this and may have missed it, but here goes:

When I have an active fermentation and krausen rolling out the blow-off tube, can I harvest that yeast for another fermentation?

 

[Qhrumphf]

https://beerandbrewing-com.cdn.ampp...s://beerandbrewing.com/dictionary/IdBjsaZjWz/

Short answer is yes. The old "Burton Union" system did something along those lines.

A mate used to over-fill his fermenters, sani a collection jar hooked to his blowoff, and that jar either jumped to a second blowoff or had an airlock on it.

 

[isomerization]

https://beerandbrewing-com.cdn.ampproject.org/v/s/beerandbrewing.com/dictionary/amp/IdBjsaZjWz?amp_js_v=a2&amp_gsa=1&usqp=mq331AQECAFYAQ==#referrer=https://www.google.com&amp_tf=From %1$s&ampshare=https://beerandbrewing.com/dictionary/IdBjsaZjWz/

Short answer is yes. The old "Burton Union" system did something along those lines.

A mate used to over-fill his fermenters, sani a collection jar hooked to his blowoff, and that jar either jumped to a second blowoff or had an airlock on it.

Would the utility of this approach by yeast strain specific or can we assume that any top fermenting yeast would yield something worth repitching from this approach?

 

[JAReeves]

https://beerandbrewing-com.cdn.ampproject.org/v/s/beerandbrewing.com/dictionary/amp/IdBjsaZjWz?amp_js_v=a2&amp_gsa=1&usqp=mq331AQECAFYAQ==#referrer=https://www.google.com&amp_tf=From %1$s&ampshare=https://beerandbrewing.com/dictionary/IdBjsaZjWz/

Short answer is yes. The old "Burton Union" system did something along those lines.

A mate used to over-fill his fermenters, sani a collection jar hooked to his blowoff, and that jar either jumped to a second blowoff or had an airlock on it.

Thank you! I will plan for this in the future as a way of “top cropping.” As I understand it, the trick is having the yeast enter a sterile location that releases pressure. I like it. I like it a lot.

 

[Qhrumphf]

Would the utility of this approach by yeast strain specific or can we assume that any top fermenting yeast would yield something worth repitching from this approach?

Probably works best with "top cropping" yeasts (ie Hefe, and some English/Belgian strains). It used to be accepted you'd skim off the top protein layer first (this method can't do that) before top cropping, but I haven't top cropped in a while so for all I know that may be outdated.

That said, it'd probably work with any top fermenting yeast, just may not harvest as much/as clean with a non-"true top cropper".

 

[KortzBrewhouse]

Could I still do this if I left my blow off tube and a jar to catch it in exposed?

 

[Qhrumphf]

I wouldn't. Not sanitary. And especially when dealing with yeast, sanitary (or better yet sterile) is key. If you pick up unwanted bacteria/wild yeast, then harvest, they'll multiply in your batch just like the yeast you DO want.

When *I* have top cropped in the past, I've always taken an active fermentation at high krausen in a bucket, opened it an skimmed the top maybe 6-8 hours prior to harvesting (say, when I start brewing), and then when I'm ready to pitch I top crop exactly the amount I need, in a sanitary container, and pitch it immediately. There's no reason the above approach won't work as well (historically has and aforementioned friend had luck with it), but as said it's not *my* approach, and I'd expect dirtier yeast, and less viability (the way I've done it I'm pitching at absolute max viability and vitality) using it.

 

[kydan47]

I found long ago that I was losing more than I wanted by just doing a blow off tube - so I use a 2nd 1/2 gal jar to collect the yeast. I do this using 3 economy air locks (one in the fermenter lid and a 2nd in the lid of the blowoff container (the 1/2 gal jar & lid from dollar store). I connect a 1/2” ID tube over the center tube of the fermenter econo lock to the center tube of the 2nd catch jar econo lock. A 3rd complete air lock in the catch jar lid vents the excess co2. Afterwards, a quick twist of the transfer tube releases the tube from the airlocks. I replace the fermenter airlock works & cap after the fermentation subsides.

 

[JAReeves]

I found long ago that I was losing more than I wanted by just doing a blow off tube - so I use a 2nd 1/2 gal jar to collect the yeast. I do this using 3 economy air locks (one in the fermenter lid and a 2nd in the lid of the blowoff container (the 1/2 gal jar & lid from dollar store). I connect a 1/2” ID tube over the center tube of the fermenter econo lock to the center tube of the 2nd catch jar econo lock. A 3rd complete air lock in the catch jar lid vents the excess co2. Afterwards, a quick twist of the transfer tube releases the tube from the airlocks. I replace the fermenter airlock works & cap after the fermentation subsides.

Oh yeah, i’m doing this.

 

[kydan47]

Oh yeah, i’m doing this.

Almost forgot! For yeasts eg hefe that have both settling yeast & suspension yeast, you only capture the one. Each subsequent pitch becomes more clearer as you go.

 

[Jtvann]

Here's a thread showing exactly what you're talking about doing, and a picture with how to set it up. Be careful about calling it a "Burton Union" though. With wikipedia nazis will educate you.

https://www.homebrewtalk.com/forum/threads/burton-union-trial-run.660407/#post-8481027