Harvesting yeast

I have read many of the harvesting yeast threads. I havent found an answer related to my question. I normally leave my beer in primary for about 4-5 weeks. It comes out nicely. Is yeast that has been in primary for that long still good for harvesting? Am I going to get too much dead yeast to use in another batch? Is there an ideal time frame for harvesting yeast? What do you guys do time frame wise?

I don't think that length of time will be an issue, though other more-knowledgeable folks will probably chime in. IIRC, the dead yeast will settle quickly with the trub, so they shouldn't pose a problem.

I've harvested after 3-4 weeks in primary without issue thus far.

I've been wondering about this too lately. If you secondary, then that yeast is supposed to be lower quality and not worth harvesting. If however, you do not use a secondary, then that same yeast will be present in the final harvest? Or are all the yeast in the extended primary all the the same? Hmmmmm. Yeah, I need to know too. I'm wondering if you can harvest a better quality from the primary, then racking.

I have limited experience with this, having harvest only one time. I harvested some WLP400 from a wit that was in the primary for 4 weeks with no secondary. I have used one jar of the harvested yeast in another wit with sucess. I did make a starter from the harvested yeast as most recommend. I had acceptable lag time and attenuation .

So for me it works thus far.

I've harvested yeast from the primary after 4 or 5 weeks with very good results; the dead yeast drops out with the trub when you do the water rinse thingy

Laughing_Gnome_Invisible said:

I've been wondering about this too lately. If you secondary, then that yeast is supposed to be lower quality and not worth harvesting. If however, you do not use a secondary, then that same yeast will be present in the final harvest? Or are all the yeast in the extended primary all the the same? Hmmmmm. Yeah, I need to know too. I'm wondering if you can harvest a better quality from the primary, then racking.

Click to expand...

it's mostly a matter of selection - if you harvest from secondary, you're selecting for poor flocculating yeasts; so your next batch with that yeast may have issues clearing (and IIRC, those poor flocculating yeast also tend to be more highly attenuative (? was it more or less? in any case, they change in other ways as well).

If you harvest from the primary, you'll still get some of those yeasts, but you get them in more-or-less the same ratio to all the other yeasts that you started with, so the population as a whole acts the way it should terms of flocculation/attenuation/etc..