positive displacement pump/peristaltic for top cropping

[woohokie]

Anyone have any recommendations on a pump for top cropping? Our yeast seems perfect for this and given our process of tail end dry hopping, not brewing enough beer that isnt dry hopped, it makes getting enough slurry pre dry hop almost impossible. This yeast seems to require a soft crash for 24 hours after its VDK rest - which I can't do if we're dry hopping prior to complete attenuation. So, I'm thinking at 50% attenuation I could submerge a ~ 1/2" sanitized end of the tubing from the peristaltic pump and drop it right into the 2" port and pump just above the beer into a sanitized converted yeast keg.

So, am I nuts? It seems like the best way to always have yeast ready to go whenever that doesn't contain dry hops. Any reco on a pump that would work well for this would be greatly appreciated. Also - wed be trying this on 7bbl/20bbl/40bbl tanks, but just 7 and 20bbl tanks for right now.
Thanks all.

[cskura]

Pd pump

You'd need to find something with a lot of suction and a peristaltic pump would do that or possibly a twin screw pump.

Overall, I don't think the process your describing is very sanitary, your best bet would be to have a 2"port added to your tanks expected liquid level, this port would also require you to cip frequently.

Just some thoughts.

Chris Skura

[gitchegumee]

Harvesting at 50% attenuation?

Not a great idea. You'll select for underattenuation and against flocculation. Best figure out how to use a different source of yeast. And you should be able to crop at least 3-4 great pitches of yeast from each batch.... BTW, we use a peristaltic pump to slowly and gently pull bottoms without rat-holing and yeast slurry from fermenter cones, as well as precision pitch our slurry. Love them.

[gitchegumee]

Further to this....

We have a larger peristaltic pump that we use with our yeast brink to pull yeast from a clean cone. Set the speed and set a timer, and we have a brink full of yeast to wheel into the cold room a little while later. No jerking around on a small stool with your hand on a valve trying to get yeast to flow correctly. Let the machine do the work while you do something more productive. Likewise, when we pull the brink out of the cold room to pitch the yeast, we recirculate the yeast on full speed, grab a sample for yeast slurry density and for viability, then pitch based on speed and time. It's very accurate--we check the cell count after pitch and at 18 hours. Could also be used to acid wash, which is on the agenda for our guys to learn soon. (Need a QA Manager to take the reins--where are QA guys/gals?). It's also the item to have for blowing down tank bottoms. Set it for speed and set your timer and walk away. No rat-holes. No wasted beer. Not to limit the tricks this thing can do, either! It's also very useful for exact dosing of finings during a transfer. Also the bomb if you use flavors, back sweeten, or otherwise want an even dosing..... Before you ask what make/model/and hose size we use, it was bought in Korea. And I wouldn't be sure what your brewery size or plant procedures are. Do a bit of math and you'll see that what you're likely after is a bit on the larger size compared to most lab pumps. And although it has a port for computer, ours does not have a simple timer, nor a revolutions counter. We have to use an external timer to remind us to walk back to stop the pump. Wish that was integrated into the unit. Good luck!

[woohokie]

Thanks for the help and info, and in the end I can't see it working out for reasons you all suggested, let alone it seems like getting enough yeast and not just foam might also be tough. Thanks again all.

[mibrewers]

What yeast strain are you using? The individual strain has a lot to do with how well it crops. At my previous employer, we would harvest from every non-spiced, 10-16P original gravity beer, and even (rarely) from higher plato beer styles. Dry hopping always happens after harvesting yeast, so no worries there. We would harvest at 2-3P above terminal, usually at 48-60 hours from pitching. Harvesting was done with a sanitized bus tub on a stick, into sanitized trash cans.

We experimented with using a PD pump and a length of stainless hose, connected to a keg, but it ended up pulling too much gas out of the solution and the yeast quality suffered immensely.

It sounds like you're looking to rouse the yeast, in order to get a better harvest, which is often necessary with the highly-flocculent top-croppers. We used sanitized Little Giant submersible pumps connected to flexible PVC hose and a fixed stainless gooseneck to recirc when necessary. It's also possible to use a simple "punch-down" stick to rouse.

Using these techniques, the yeast was easily pushed into hundreds of generations without acid washing or reculturing.