Harvesting lager yeast from a corny keg

[McMullan]

Just thought I'd share this, in case anyone wants to try something similar. I usually top-crop ale yeast. Harvesting lager yeast for repitching is something new for me. I'm hoping to get a better fermentation repitching more healthy yeast

So, I don't drink much lager, but I've been enjoying a personal challenge to make some I'd be happy to serve, especially during the hot summer months. Basically, I've been brewing half batches and fermenting them in what were redundant 19L corny kegs. After transferring the beer to a 9L keg for lagering, the remaining small volume of beer was tapped off until the keg 'blew'. I gave the keg a good swirl then put it on its side, tilted towards the top with the gas post at 6 o'clock. Left it sitting there for a while, maybe 30 minutes or so, before connecting a collection bottle. I use a floating dip tube for beer out and a shortened gas dip tube so I can drain all sanitiser from the keg. I realised the shortened gas dip tube is going to help collect yeast slurry, too. Well, some pictures explain it better:

Concentrated active yeast slurry under CO2 (no oxygen) stored in the fridge, ready for repitching tomorrow.

 

[odie]

genius...I gave up harvesting keg fermented yeast when I switched to a floating dip tube.

 

[beerfactory]

this is genius - much more sanitary than what I am doing, which is a Winco Stainless Steel Ladle, 5-Ounce and canning jars

 

[stevehaun]

Why not just open the lid and pour the yeast slurry into a sanitized container?

 

[McMullan]

Why not just open the lid and pour the yeast slurry into a sanitized container?

Dribbling concentrated slurry from a corny keg is a PITA, if you ask me. The method here worked very well for me and I'll carry on using it for harvesting lager yeast from half batches fermented in a corny keg. There's not really much setting up either. What you see is the set-up for spunding when the keg is upright. And the pressure to push the slurry out is already in the keg. Why not use? I like that the method collects concentrated slurry (no beer carryover) under CO2, too, which probably keeps the yeast happier for longer than air.

 

[McMullan]

Here's the shortened 'gas' dip tube, with a standard gas dip tube.

Without any protrusion inside the keg the gas/in post gets a lot more useful. Not just for harvesting yeast, but draining excess sanitiser too.

 

[Brooothru]

Here's the shortened 'gas' dip tube, with a standard gas dip tube.

View attachment 762047

Without any protrusion inside the keg the gas/in post gets a lot more useful. Not just for harvesting yeast, but draining excess sanitiser too.

Cool trick. I'll use this to harvest from a kegmenter. Thanks.