Sanitary Top-Crop Yeast Harvesting
Posted: Wed Jul 21, 2010 3:34 pm
http://www.flickr.com/photos/33275630@N ... 428865599/
Here's a link to some pictures of a sanitary top-cropping system to harvest yeast that I put together a few weeks ago. Basically all I'm doing is cutting a slit in a $1 closed cell foam stopper (which I typically use for making starters) and pushing a piece of blow-off tubing through it. The foam stopper allows the blow-off reservoir to breathe, while remaining sanitary.
One of the nice features of the system is that it allows you to grab the healthiest yeast from high krausen, rather than trying to harvest the leftovers from the bottom of the fermenter. (In the case of this 10% Scottish Strong Ale, I have to believe the top-cropped yeast is much healthier than the yeast at the bottom of the primary fermenter, although I can't prove that.) Additionally, if the fermentation gets stuck, you can just pitch some starter wort into the harvested yeast, wait 12 hours, and then pitch that back into the primary.
I haven't bothered to try and estimate the cell count in the slurry, but to me it looks like about 3 vials/smack-packs worth.
Tim's using the yeast from my trial run right now -- hopefully he'll report back on how it performed.
Here's a link to some pictures of a sanitary top-cropping system to harvest yeast that I put together a few weeks ago. Basically all I'm doing is cutting a slit in a $1 closed cell foam stopper (which I typically use for making starters) and pushing a piece of blow-off tubing through it. The foam stopper allows the blow-off reservoir to breathe, while remaining sanitary.
One of the nice features of the system is that it allows you to grab the healthiest yeast from high krausen, rather than trying to harvest the leftovers from the bottom of the fermenter. (In the case of this 10% Scottish Strong Ale, I have to believe the top-cropped yeast is much healthier than the yeast at the bottom of the primary fermenter, although I can't prove that.) Additionally, if the fermentation gets stuck, you can just pitch some starter wort into the harvested yeast, wait 12 hours, and then pitch that back into the primary.
I haven't bothered to try and estimate the cell count in the slurry, but to me it looks like about 3 vials/smack-packs worth.
Tim's using the yeast from my trial run right now -- hopefully he'll report back on how it performed.