Spin time

As yeast viability goes down and the vial gets closer to the best before date, would increasing the length of time in the starter or a bigger starter do any good to increase total cell count? Or would you have to start, clean, make next starter be the way to get the cell count up to where it needs to be? I have a vial that is getting close to their BB date. I am going to do a 2L starter. I usually let it spin for 18-24 hours before pitching. Would any extra spinning time or bigger starter do anything for the cell count?

 

You're only going to get so many reproduced cells from the yeast per "step" of the starter. This is the reason we have to either begin with more viable cells which in turn create even more cells or in the case of a lesser number of viable yeast we have to increase the number of steps. A larger volume of starter wort off the bat isn't going to do anything other than waste wort. As far as increasing the time on the stir plate, once you have achieved reproduction, you have reached reproduction. The yeast is just going to go into fermentation mode instead of staying in any type of reproductive phase.

 

Thanks. I haven't stepped a starter yet. Been reading about it. Suppose it is time to try.

 

I used a lager yeast 10 months past it's best by date. It took a little longer to get going (1 L starter). I also used FermAid K.

After letting it settle, I decanted and stepped it up to a 1.5L starter...the yeast did a fine job.