How far can yeast go with a starter? 10, 15, 20 gal??

[user 227424]

Just beginning to make starters, and not sure I fully understand the science of yeast. Can a single Wyeast or Safbrew be multiplied any number of times, to pitch any number of 5 gallon batches, in theory?

I'm about to make a starter and divide it in half to pitch two 5gal batches and wondered how far one could go with it? Three, four, six 5gal batches??

Thanks!!

 

[mredge73]

Use a calculator like this and play around with the numbers:
https://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/
You can make a 4 gallon starter to ferment 50 gallons with a single vial for example.
So to answer your question, it is dependent on how big you make the initial starter.


I don't remember where I read it but it isn't advisable to harvest yeast more than 8 times.
I also just realized this has nothing to do with what you are asking about.

 

[day_trippr]

All other metrics being equal, the volume of a starter vessel will pretty much set an upper limit on yield.
You can literally get into the case that pitching from one starter to a fresh batch of starter beer will have unity gain - or even lose cell count.

If you have a large enough vessel you can crank out enough yeast to pitch any size batch.

I favor the Brewer's Friend starter calculator for a number of reasons, one of which is the heads up it'll give when you get into the above scenario...

Cheers!

 

[Tarpon87]

It sounds like you are asking how many times the yeast can be used, not how large of a batch you can make. I asked a similar question recently and the answer is "it depends". You can use it until you get a mutation that causes a characteristic in the beer that you dislike, then start with a fresh packet.
What i do is, using a fresh packet or vial of yeast (or dregs from bottles as was the case with my latest batch) and using the brewers friend calc or mr malty calc i make a starter roughly 1 1/2 times larger than what i need for the batch. Cold crash, decant most of the beer and pour 1/3 of the starter into a sanitized mason jar to use for a future starter. I pitch the 2/3 left over into my current batch.

 

[user 227424]

Thanks all!