Yeast starter: viability/vitality

[UKSkydiver]

Hey all.

I have some CML Hog Norsk top crop. It was cropped Dec 2021. When I did the original brew it was a really healthy ferment, producing loads of yeast.

Yesterday I thought I'd make a 1200ml starter with 3-4 (or 5 I didn't count) good heaped teaspoons full of the harvested yeast to kick start it before pitching later today.

We're coming up to 24 hours on the stir plate and it looks like a muddy puddle: no krausen.

It could be I'm expecting too much too soon, but given the original ferment, I was kinda expecting it to show some signs of life.

Can I get your collective thoughts please?

Thank you.

 

[matt76]

If it was a vitality starter you were aiming for (a.k.a. shaken not stirred) then you need to put your wort in a bottle 4-5 x the volume of your starter and shake the living daylights out of it for a few minutes to oxygenate it before pitching the yeast - the whole idea is to avoid the need for a stir plate.

This has worked really well for me recently but only with dried yeast or recently harvested slurry (<4 weeks old roughly).

If you're doing it the "conventional" way using a stir plate I'd have thought you'd need longer than 24hrs, especially if the yeast has gone dormant. The clue I'd be looking for on a stir plate is it goes kinda from a strong-tea colour to milky-tea.

My guess would be your yeast will need a few more days to really get going in the starter. You could chance it and pitch it, it might work, or use a fresh pack if you have something suitable.

(Personally I'd probably chalk it up to experience and pitch something else, others may disagree)

 

[UKSkydiver]

Thanks Matt

I thought, based on the previous ferment, that this was only going to need a bit of a nudge to wake it up.

I will leave it on the stir plate for another half day and see if there are any signs. If not, I'll pitch a dry yeast from stock.

I really wanted to reuse this yeast #sadface

Cheers

 

[matt76]

Thanks Matt

I think, based on the previous ferment, that this was only going to need a bit of a nudge to wake it up.

I will leave it on the stir plate for another half day and see if there are any signs. If not, I'll pitch a dry yeast from stock.

I really wanted to reuse this yeast #sadface

Cheers

No worries

FWIW, just for a laugh I pitched a small amount of ~2yr old WY1098 slurry into some spare wort a few days ago. Little or nothing yet but I looked earlier and it might have just been showing some initial signs of waking up so there's always hope

 

[UKSkydiver]

It's still a bit murky, but there are signs of CO2.

I suspect my expectations did not match reality and I should have started this off a couple of days earlier.

With any luck I get to use this yeast though.

Cheers