[philm63]

I thought this was supposed to be a vigerous fermenting strain. I did a Kolsch last Sunday and pitched at 60 F. I made a 1.3 L starter on a stirplate - YeastCalc tells me I needed around 193 B, and also told me I'd get 277 B with a 1.3 L starter on the SP so I figured it'd be a nice healthy pitch.

The activity in the fermenter was low - only about an inch or so of krausen. I even used a blow-off tube on this one thinking it would make a mess otherwise. Also, Thursday morning showed the krausen had dropped and the beer was pretty clear on top - just a few bubbles here and there. It was still putting CO2 bubbles in the flask of StarSan my blow-off tube was in - about every 5 or 6 seconds - so I know it's still fermenting.

Was the seemingly low fermentation activity normal for this strain at 60 F? Or did I miss the mark on the pitch and make too small a starter for such a low fermentation temperature? The thinking here is that as the fermentation temperature decreases, the initial cell count needs to increase... does this make sense?

[tommymorris]

It's probably just slow at 60F. If you have a krausen your good to go.

Back when I had a glass carboy there were beers that never got more than an inch or two of krausen.

Also I have used WLP029 and don't remember it being really fast to ferment.

[tommymorris]

Wait. The krausen already dropped? Are you sure it's not finished? Did you take a gravity reading?

[morticaixavier]

Yeah, that yeast is a bit finicky that low. But it sounds fine. A big giant krausen and lots of blow off isn't ideal behavior especially for a clean crisp style like kolsch. What you are seeing is good. You could safely bump the temp a couple of degrees at this point to help it finish up if you like

[philm63]

Wait. The krausen already dropped? Are you sure it's not finished? Did you take a gravity reading?

Taking the first reading tonight - fingers crossed...

Yeah, that yeast is a bit finicky that low. But it sounds fine. A big giant krausen and lots of blow off isn't ideal behavior especially for a clean crisp style like kolsch. What you are seeing is good. You could safely bump the temp a couple of degrees at this point to help it finish up if you like

Yeah, I'd already been bumping it up slowly since fermentation slowed down Wednesday - I'm at 66 F now and will let it finish out there.

Thanks for the replies.

[S. cerevisiae]

Your pitching temperature was too low for that strain.

For White Lab's website (http://www.whitelabs.com/yeast/wlp029-german-ale-k-lsch-yeast):

Optimum Ferment Temp.  65-69°F, 18-20°C (Does not ferment well less than 62°F, or 16°C, unless during active fermentation)

[morticaixavier]

Your pitching temperature was too low for that strain.

For White Lab's website (http://www.whitelabs.com/yeast/wlp029-german-ale-k-lsch-yeast):

Optimum Ferment Temp.  65-69°F, 18-20°C (Does not ferment well less than 62°F, or 16°C, unless during active fermentation)

yes and no. it gets persnickity below 62 but works and produces a very clean crisp beer at that temp. I've heard it will stall below 58 though.

[philm63]

Tell ya what, though; even at 60 F this thing fermented out completely in 5 days. Successive gravity readings on days 6 and 7 showed a consistent 1.007 - done! Dropped very clear, too. Sample tasted very good. Me happy.

[ynotbrusum]

I have used this in many Kolsch recipes over the years and it worked for me at 58F - I just left it alone for a month and kegged it from the primary.  Easy peasy good clean ales.