Yeast farming question

Ok, please forgive me if this is somewhere else (I'm sure it is, just didn't know how to search for it). I'm about to foray into yeast ranching to get a stash of pacman going. I understand the process, but here is my question: say after my wash I have about 4 jars or so of slurry. I understand that those are good for a couple of months to over six months, ymmv. But what if I take one of those jars and pitch to a starter for a new batch- then harvest again after primary. can this be done ad nauseum, or is there a limit to the number of times you can re-harvest? If yes, why? Just trying to figure out the mechanics of it all...
Thanks,
Natalie

You can harvest again, but as generations increase so does the probability of mutations in the yeast, eventually resulting in different characteristics.

It might change into something interesting or something worthless, that's up to Darwin.

I've read two recommended limits. 4 generations and 10 generations.

I do something a little different. I make a starter larger than I need when I get a new yeast. I have 20 ml vials and make 4 up for freezing.

I use 5ml yeast, 5ml glycerin and 10ml water. I have used some that was over 6 months old so far and my oldest is now over 9 months old.

I do step starters to make a new batch. If I were to make a new set of 4 vials each time for 4 generations I could make 256 batches from the original vial/smackpack.

kh54s10 said:

I've read two recommended limits. 4 generations and 10 generations.

I do something a little different. I make a starter larger than I need when I get a new yeast. I have 20 ml vials and make 4 up for freezing.

I use 5ml yeast, 5ml glycerin and 10ml water. I have used some that was over 6 months old so far and my oldest is now over 9 months old.

I do step starters to make a new batch. If I were to make a new set of 4 vials each time for 4 generations I could make 256 batches from the original vial/smackpack.

Click to expand...

I do the same thing...50ml vials from a large starter. Freezer storage is also important to a successful next generation. As most freezers are frost free, they periodically warm up, which is not so good for stored yeast. Although not as much of an issue for the OP in that volume.

I re use us05 all the time. The only thing that I've noticed from later generations is that the flocculation increases (clearer) and the attenuation decreases slightly (sweeter). I put this down to later generations and harvesting the more flocculant yeast and then re using that. I reckon that when using yeast over and over you end up leaving the less flocc and more atten yeast in suspension and therefore get more high floc low atten yeast.
Just my 2c.
Gab.