Yeast Propogation Temperature

[jipjanneke]

I'm trying to batch up some Wyeast Kolsch yeast for an up-and-coming brew. My question relates to correct/optimal propgation temperature ... Wyeast's website recommends 75oF (24oC), however Kolsch yeast is happily fermenting at 55-64oF (13-18oC).

So, should I propgate at 75oF or 60oF to get 'best' propogation outcome? And how would you define 'best' (fastest? most healthy/viable? pitch-ready?).

Any advice and/or experience welcome...

Thanks.

[NickHorne]

I'd propigate @ 13-18* whatever the fermtemp will be or close to it.
to minimise shocking them.

[SmellsLikeBeer]

our brewery normally ferments at 64-68 degrees. However, we keep our yeast prop at 70-75 degrees. The previous brewery I worked at was similar.

I think "shocking the yeast" is over-rated. After all, every yeast harvest we do is at 30-35 degrees, it is subsequently pitched in wort of 64, perhaps 70 degrees. Talk about "shocking the yeast"........

[Sir Brewsalot]

Is the thinking here that we don't really care about the ester levels of that small prop batch, we just want lots of big ol healthy yeast, ready to eat.. right? I figure yeast would "like" to be at 75 or so, but we run it colder when it's a drinkable product we're after.

Am I even close?

[dick murton]

"however Kolsch yeast is happily fermenting at 55-64oF (13-18oC)" Wow. That is a heck of a big range for a single yeast strain. We normally aim to culture in final culture vessel at the same temperature as the main FV temperature. However up to 2 deg C gives better yeast growth, without generating too many weird flavours.

It is a balance between rapid yeast growth and off flavours if too warm. I suggest that 75 deg C is far too warm except in the conical flask step of growth , with another couple of steps to follow, each, in your case getting progressively coller by a degree or so.

Ultimately though, it is your decision based on viability, growth and flavours attributable to the culture.

Hope this helps. Cheers