How long will a yeast starter last?

[MyCarHasAbs]

I was going to brew today and the starter has been in prep for about 24 hours. I've had an emergency come up and it doesn't look like brewing is going to work out. Worse case scenario, I have to go back out and get more yeast. Just curious how long it can sit on the stir plate without going to waste.

 

[MyCarHasAbs]

Update: it's in the fridge with plastic wrap over the foam topper. Will plan to brew this coming Saturday. Hopefully the cells will survive till then.

 

[ThatVideoKid]

Oh yeah your fine don't worry about it. You might want to re-energize then with some more wort, but they're fine.

 

[jpakstis]

My typical MO is to create a starter about 4-5 days in advance of the brew day. After a couple of days on the stir plate (when the wort looks really creamy) I will put in the fridge (and harvest about 8 ounces for future use). It's been no problem waiting until the weekend and once I had to wait another week and had no issues.

 

[Brew_G]

I have started to step up my starters twice, in an attempt to pitch them while the yeast are highly active. I'll make my first step about a week out, then split that starter (keeping about 2/4 for the upcoming beer) and crash it. Then, the night before brewday, I step it up, aiming for a 25-30% over pitch since I'll be pitching the starter at 12-18 hours after that step (thus not giving the yeast time to use up all the sugars in the starter).

I do this with slurries that are plenty old, and I wouldn't have any issue with pitching a few-week-old starter that had a near-ideal cell count when I pulled it from the stir plate.