I was about to make a second step to my lager yeast and started to wonder if temperature is an issue with this. I fermented at room temp on the stir plate, chilled to 40, decanted. Will pouring room temp wort on top of “cooler” yeast stress the yeast out or cause a reduction in reproduction of cells? I know lager yeast prefers cooler temps but i assume that’s only to prevent off flavors and has little to do with increasing cell count. Am I correct in this thinking?
You are correct. Fermenting beer and building yeast counts are totally different. That doesn’t mean to go crazy with heat but room temps are just fine as long as you plan ahead and decant the starter liquid.
This is my understanding as well – I’ve used the procedure you outlined as standard practice for a while now (usually stepping up from 1 to 2 liters after decanting) with no ill effects. I also decant and pitch straight from the refrigerator into primary (for both lagers and ales) and have never had a problem with off flavors in the final product.