How long can I leave my starter on the stir plate?

Friday night I made a 1L starter with a vial of WLP001. My plan was to brew today, monday, but now it turns out I can't brew until wednesday.

I don't want to overpitch, how should I do this? Can i make them go to sleep, and then wake them up again?

Smellyglove said:

Friday night I made a 1L starter with a vial of WLP001. My plan was to brew today, monday, but now it turns out I can't brew until wednesday.

I don't want to overpitch, how should I do this? Can i make them go to sleep, and then wake them up again?

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They'll be fine sitting on the stirplate until Wednesday. If it's all fermented out, you could put it in the fridge but you don't have to.

I would put it in the fridge to force the yeast to flocculate out. On brew day, decant the extra liquid and pitch the yeast.

Alright. But what's the difference in pitching an active starter and not? Shorter lag-time?

And if I don't put them in the fridge, what will happen then? Will they die? Start to cannabalize? Putting out off flavors?

Smellyglove said:

Alright. But what's the difference in pitching an active starter and not? Shorter lag-time?

And if I don't put them in the fridge, what will happen then? Will they die? Start to cannabalize? Putting out off flavors?

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Don't worry, it won't die in the fridge, or anything else. It'll be fine--the yeast will just go dormant. A few hours before you pitch, take it out, decant most of the spent wort (leave a few ounces of wort in there). Then keep it at room temp to warm the yeast back up. Give the flask a swirl to get the yeast off the bottom, and pitch.

MaxStout said:

Don't worry, it won't die in the fridge, or anything else. It'll be fine--the yeast will just go dormant. A few hours before you pitch, take it out, decant most of the spent wort (leave a few ounces of wort in there). Then keep it at room temp to warm the yeast back up. Give the flask a swirl to get the yeast off the bottom, and pitch.

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I meant if I don't put them in the fridge, what will happen then? But will they maybe just overpopulate? Or will some of them die due to the small size of the wort?

Smellyglove said:

I meant if I don't put them in the fridge, what will happen then? But will they maybe just overpopulate? Or will some of them die due to the small size of the wort?

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Nothing will happen to them in 48 hours. Nothing at all.

Yooper said:

Nothing will happen to them in 48 hours. Nothing at all.

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I'm really starting to like these one-celled little guys.

You should be good. I made 2 starters last Wednesday for a planned brew day of Saturday. I gave myself the extra time because they were both British yeasts and I'd had some trouble with slow starts in the past.

Both vials turned out to be fresh enough that my starters had fermented out and dropped clear by Thursday night.

I left both on the starter wort, unrefrigerated, until Saturday. While chilling my beer, I decanted all but about 150ml of the starter beer. Pitched into chilled wort at 6 pm.

Both had positive pressure in the airlock when I went to bed at 11. When I woke up at 630, I had active fermentation with about an inch of krausen in each.

If you think about it, even if you're using a secondary, you let a beer sit a few days after active fermentation before racking. Allowing a starter to sit for a couple of days is essentially doing the same thing on a smaller scale.

winvarin said:

If you think about it, even if you're using a secondary, you let a beer sit a few days after active fermentation before racking. Allowing a starter to sit for a couple of days is essentially doing the same thing on a smaller scale.

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Yeah, I know I shouldn't be worried after the answers I got. Now my brewday has been postponed another day, but I guess I'll be alright. But I'm still unsure about what happes to my yest in general. Which isn't a question you guys should feel to take your time to answer. I just have to read YEAST one more time or two.

Smellyglove said:

Friday night I made a 1L starter with a vial of WLP001. My plan was to brew today, monday, but now it turns out I can't brew until wednesday.

I don't want to overpitch, how should I do this? Can i make them go to sleep, and then wake them up again?

Click to expand...

Smellyglove said:

I meant if I don't put them in the fridge, what will happen then? But will they maybe just overpopulate? Or will some of them die due to the small size of the wort?

Click to expand...

You seem to think the yeast will keep multiplying ad infinitum. Yeast don't work like that. After 2 days on the stir plate, they're done multiplying.

Second thing: by all means turn your stirplate OFF! Don't want to keep beating up your poor yeasties 2-3 extra days for no reason. This will also allow you to decant off some of the starter beer if desired.

I always decant the starter culture and resuspend the yeast in wort (~.5 L) from the beer I'm brewing and let it go until I'm done brewing. I don't like the idea of "old beer" in my fresh beer