second stage of yeast starter, decant first or just add more wort?

I've seen mixed instructions on how to do a second stage for a yeast starter - some of them say to decant first, and others just say to add more wort. Is one more correct?

Also, if you decant first, does that mean you put it in the fridge, then decant, wait for it to warm up, and add more wort again?

I prefer to decant first. It doesn't really matter either way though. I only decant because the jug I use for starters isn't big enough to hold larger amounts of liquid. I refridgerate mine for 24 hours, then decant and add more wort when it warms up.

Stupid question,

Why do you do a second stage? because your starter container isn't big enough?

Rover said:

Stupid question,

Why do you do a second stage? because your starter container isn't big enough?

Click to expand...

It's not a stupid question, I was wondering the same thing yesterday. I didn't find a definite answer, but got the impression that it has something to do with the ratio of yeast to wort being good for the yeast. Maybe someone else can answer that question too...

In addition to his pitching calculator Mr Malty (Jamil Zainasheff) has a FAQ here: http://www.mrmalty.com/starter_faq.htm.

I'm assuming second stage starters is the same as "stepping up" a starter which is, as you surmised, done to increase the amount of yeast. While you can decant the best way is to add more volume. This is because yeast growth is density limited - ie the yeast can tell when there are too many around and will stop reproducing. Of course you may be limited by the size of your starter container so decanting is your only option.

GT