Is a step up starter considered a new yeast generation?

[mtnagel]

I know there is a limit on the number of generations you should go for before you stop reusing your yeast (and that number is up for debate). I'm assuming that a full fermentation in a "normal" strength beer is considered a new generation, right?

But is every step starter I make a new generation that counts against that limit? If I use a smack pack and it takes 2 steps to get up to correct pitching amount, am I now on generation 3?

I guess you have no idea what generation you are on when you harvest from a bottle, but I just harvested some yeast from Heady Topper and I used 4 steps to get up to enough yeast to split up and store. Assuming I started at generation 1, am I now on the 5th generation against the limit?

 

[el_caro]

All my reading and questioning on this question has led me to understand that steps in a starter do not count as generations.

As to how many times yeast can be reused that depends on many factors and hence it would be difficult to quantify. If the yeast was never stressed and handled optimally then it has been suggested even 100 reuses may not be an unrealistic number.

 

[mtnagel]

Thanks for response. So I'm assuming saving yeast from a starter would be less stressful than after fermentation of a batch, right?

 

[tally350z]

Yes. What I normally do is when I get a vial of yeast and make my starter I make it larger than I need too. If I need 1L, I make a 1.5L. Then I pitch my appropriate amount and save the rest in a sterile mason jar until needed. Then make another starter and so on.
As long as you use proper techniques for handling,washing and storing, there is no reason you couldn't reuse the yeast from a previous batch. Just don't want to use one that has a high OG, as they could be stressed out too much.

 

[el_caro]

Yes. What I normally do is when I get a vial of yeast and make my starter I make it larger than I need too. If I need 1L, I make a 1.5L. Then I pitch my appropriate amount and save the rest in a sterile mason jar until needed. Then make another starter and so on.
As long as you use proper techniques for handling,washing and storing, there is no reason you couldn't reuse the yeast from a previous batch. Just don't want to use one that has a high OG, as they could be stressed out too much.

Similar to my approach. I grow it up a bit more and aim to save into 2 or 3 x 50ml vials (approx 100bn cells in each) .

 

[maddcow]

I'm glad this question was asked. I've wondered the same thing myself. The more I sit around at work, the more I learn from HBT. Hahah

 

[TheOnionKnight]

I just learned something new today too...while at work

 

[Cyclman]

It is the stress that can limit how many generations of yeast should be used. Also contamination. Stepping a starter, these aren't generally an issue, assuming good practices.

After all, in some sense the vast majority of the yeasts we use are generations. Maybe they are generations under highly controlled laboratory circumstances, but it's not like new yeasts are being pulled from a yeast plant somewhere. Bud claims their yeast is 130 years old. They have certainly mastered consistency, if not flavor.

 

[mtnagel]

Yeah, that's what I was thinking. About the yeast we buy from yeast companies. Of course their process is much more controlled than my kitchen counter and stove.

 

[LoloMT7]

I'm glad this question was asked. I've wondered the same thing myself. The more I sit around at work, the more I learn from HBT. Hahah

Another day of learning new things for me also. Thank you HBT!

 

[MindenMan]

I had also wondered about "generations" The yeast in my fridge was collected after one generation of use, and I re-starter it every time I brew. Over the course of the last year, I just kept re pitching onto the yeast cake of the prior batch, and so on. Somewhere along the way, I picked up some sort of infection, and the yeast (ESB 1968) started to attenuate to 90%, and completely killing each batch I did. Back to the point I originally started, my once used batch of yeast keeps re-getting fed and restarted every batch. I now just throw out every yeast cake these days just in case.