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Author Topic: rehydrated dry yeast temperature shock  (Read 3549 times)

Offline Steve Ruch

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Re: rehydrated dry yeast temperature shock
« Reply #15 on: January 18, 2015, 09:14:13 am »
I'm surprised to hear a recommendation to rehydrate at 100F. While I do boil my rehydration water to help sanitize it, I do let it cool to room-temperature before adding the dry yeast.

They recommend 105 degrees in Yeast, though I think some manufacturers recommend closer to 95 degrees. 

This is interesting though: http://seanterrill.com/2011/04/01/dry-yeast-viability/
I've read both recommendations which is why I asked about the middle in my post.
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Offline archstanton

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Re: rehydrated dry yeast temperature shock
« Reply #16 on: January 18, 2015, 10:14:53 am »
I'm surprised to hear a recommendation to rehydrate at 100F. While I do boil my rehydration water to help sanitize it, I do let it cool to room-temperature before adding the dry yeast.

They recommend 105 degrees in Yeast, though I think some manufacturers recommend closer to 95 degrees. 

This is interesting though: http://seanterrill.com/2011/04/01/dry-yeast-viability/
I've read both recommendations which is why I asked about the middle in my post.

To be fair the yeast book says the most common range  is 95-105, and that you should find out from the manufacturer what temperature is ideal. They also say warmth is critical to cell membrane health and that colder temperature will cause more  of the cell to leach out. Who cares if the cell is alive if it is too weak and fragile to be of any use.  Vitality can be more important than viability.

IIRC Fermentis recommends 80 +/- 6 for s-04 and us-05