Author Topic: Cold Wort - Warm Yeast  (Read 3633 times)

Offline davidgzach

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Re: Cold Wort - Warm Yeast
« Reply #15 on: January 19, 2013, 10:49:36 AM »
I don't think there's much, if any, negative effect of pitching cold yeast into warm wort. I pull my starters out of the fridge, decant, and pitch immediately as my standard method. So you're taking about roughly a 30 degree temp difference. The yeast always perform great.

Yeah, same method for me.

Learn something new every day!  Thanks for saving me valuable yeast warming time.... ;)
Dave Zach

Offline tschmidlin

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Re: Cold Wort - Warm Yeast
« Reply #16 on: January 21, 2013, 05:37:04 PM »
First, let me say there are strain to strain variations and the research I am familiar with was done on S. cerevisiae strains.

It really depends on how cold the wort is.  If it is under 50F then you can induce the near-freezing response, which will have the cells doing all kinds of useless things (from a fermentation perspective) which just sucks energy out of them.  Since it is already at 66, dumping it into something at 55-60F should be more or less harmless.  There is the tendency to flocculate at colder temperatures, but the presence of glucose represses flocculation so I'm not sure which would win out - probably temp and strain dependent.  You can cold shock the yeast, but virgin cells (half of your culture) don't recover as well as mother cells.

Prudence would say to avoid it if you can.  If you can't, then RDWHAHB.
Tom Schmidlin