Yeast Rehydration and Restarting stuck Ferments

[Mash]

This subject comes up from time to time.

I thought I would share the latest thinking from my course. The process of rehydration & restarting a stuck ferment are in the attached PDF.

Best Practise Yeast rehydration- .pdf

(76.51 KiB) Downloaded 90 times

The key points for me, seemed to be that

- Yeast don't like being started - they prefer simple rehydration in water (to recover them from their dried state). Once rehydrated they can then acclimatise to their environment. if you start them, they go through the acclimatisation process (lag) twice and this can cause yeast shock (failure)

- Yeast prefer to be rehydrated in water - not high concentrate sugary/wash/wort/mash.

- Rehydrating will lead to a much greater cell count per ml than sprinkling, important for speciality yeasts. That said if using Baker's yeast it's sooo cheap, dosing at 100 g per 25 L mitigates that.

-For obvious reasons dechlorinated water (boiled) is best.

This is for dried powdered yeasts only.

[spot]

I've read this several times now and adjusted my workflow. It raises issues I hadn't known about.

[vino-tinto]

When I first read this post I thought no way would I subject beer yeast to 37C.

So I did a little research into beer yeasts and found to my amazement just what temps beer yeasts can handle.

So it seems I have been doing it wrong all this time, the only thing that's really important is the temp of the rehydrated yeast mix when pitching it.

[Mash]

When I first read this post I thought no way would I subject beer yeast to 37C.

So I did a little research into beer yeasts and found to my amazement just what temps beer yeasts can handle.

So it seems I have been doing it wrong all this time, the only thing that's really important is the temp of the rehydrated yeast mix when pitching it.

Yes indeed. Also important to rehydrate in water not is sugary water.

[Curmudgeon]

Apologies for dumb question, but what's the thinking re water from hot tap being most de-chlorinated?

[Mash]

Holding water at temperature will reduce the chlorine load.

My hot water tank is set at 60c.

[Easydrinker]

This subject comes up from time to time.

I thought I would share the latest thinking from my course. The process of rehydration & restarting a stuck ferment are in the attached PDF.

Best Practise Yeast rehydration- .pdf

The key points for me, seemed to be that

- Yeast don't like being started - they prefer simple rehydration in water (to recover them from their dried state). Once rehydrated they can then acclimatise to their environment. if you start them, they go through the acclimatisation process (lag) twice and this can cause yeast shock (failure)

- Yeast prefer to be rehydrated in water - not high concentrate sugary/wash/wort/mash.

- Rehydrating will lead to a much greater cell count per ml than sprinkling, important for speciality yeasts. That said if using Baker's yeast it's sooo cheap, dosing at 100 g per 25 L mitigates that.

-For obvious reasons dechlorinated water (boiled) is best.

This is for dried powdered yeasts only.

Has anyone thought to inform the Allinson's yeasties that this is the way that to play?
I just need to find me a use for a speciality yeast.
I don't think it will happen with stillin'

Robert.