When to harvest ale yeast from conical fermenter?

[Smiffy]

Now that I have a conical fermenter and will be able to drain yeast at any time, the question is which yeast to save?

My thinking is that the yeast which settles to the bottom early on is not the yeast which is working well, and that the yeast which is working well (top fermenting ale yeast) won't settle until the fermentation is coming to an end.

So, can anyone tell me which day's yeast is the best stuff to save for the next brew?

[Smiffy]

Instructions! Those would be interesting to see. I doubt if the people making or selling my fermenter would have any idea.

[Smiffy]

Now I have the transparent tube above the fermenter drain tap (and a 1" tap), and I'm doing the next brew using the "selected" yeast (mid to end of fermentation) from the previous experiment, I can report on its progress after 1 day. The drain appears to contain only trubb, no yeast. I think this is good because it means all the yeast is working (and floating). I will drain this and report again when the yeast starts to settle.

[Smiffy]

[Grant R Baker]

Interesting idea.

 

Easy enough to take apart for cleaning...?

[Smiffy]

Yes. Lots of pieces though. It will need it too as there is a gap between the tapered end of the hose barbs and the hose.

Day 2 update. There is no yeast sediment yet, in fact I can see fermentation taking place, a stream of rising bubbles. More confirmation that I have selected the "best" yeast.

When I drained it yesterday, when the valve was slightly opened, a bubble of air rose up the tube. This will be the air trapped inside the ball part of the ball valve. Obviously introducing air later on is going to be bad, so from now on I will block the air-lock first to allow a slight pressure build up inside to prevent this happening. I don't think this happened when I had the 1/2" valve, and it could be due to the design of the valve causing one side to open before the other, but I can't look at that while the tap is in use.

[Smiffy]

After 3 days, the bubbling from the airlock had reduced, but it was still going. I closed the valve on the airlock and allowed it to build up some positive pressure for an hour or so, then drained off 300 ml of yeast, then reopened air-lock (gently).

After 4 days, bubbling has almost stopped. Repeated the same procedure, but this time the yeast seemed a bit stuck to one side, so I drained a bit, then left it for a while then drained some more. The disturbance gave the fermentation a little kick as the airlock bubbling was increased a bit afterwards.

The rest of the yeast will be drained, but will be discarded.

[Grant R Baker]

Sticking on the Conical is always going to be the problem. One site I read talked about using a heating belt wrapped around the lower conical part, heated an hour or two before draining to help it slide.

 

Good idea about the positive pressure tho.. that should help push it out.

 

I am fairly sure you don't have to get all of the yeast cake out before secondary fermentation... just enough to drop the percentage going into your bottle or keg when its ready.

[Smiffy]

At this time, its all about saving the good yeast for re-use, and the yeast cake which was tending to stick to one side of the tube was only a momentary problem, I closed the tap, let it settle for an hour or so, then drained a little more.