Suck fermentation Dopplebock 1.029 target 1.018

[Steve b]

I have a dopplebock in the fermentor been in for 11 days fermentation stopped about 4-5 days ago I have been taking gravity readings with refractometer been 1.029 now for 3 days target 1.018 is this a stuck fermentation what shall I do , help??

[Ralph]

What temperature is is sitting at?

Have you tried "rousing" the yeast by picking up the fermentor and giving it a good shake around?

It does sounds like a pretty suck fermentation...

[Dougal]

Provided you pitched enough yeast, and depending on temperature, lager yeast are usually pretty good at slowly chewing through the sugars. On a big beer like a Doppelbock I'd still raise the fermentation temp a few degrees toward the end to help it finish out. Which yeast are you using, how much did you pitch, and what was the pitching temp?

[Steve b]

Hi there thanks for reply it was a souther German larger yeast wlp838 , said on package to flitch at 70-75 f roughly 21-25 c I pitched at 21c but got bubbling day after but not alot of it compared to my pilsner next to it which needed a blow off valve , I'm alittle confused now just looked here http://www.brewshop.co.nz/southern-german-yeast-wlp838.html
It says Optimum Fermentation Temperature: 10-13°C different to the label

[Dougal]

Sounds like you're fermenting too hot for a lager if you're still at 21C. I usually pitch at 8 and ferment at 10C for a really clean flavour profile, and other folks pitch around 18C and ferment at 10-12C, which makes for a slightly longer conditioning time. Did you make a starter or just throw the vial in? If you didn't make a starter to grow up the yeast in the vial, there probably aren't enough yeast cells to finish fermenting a big beer like that.

Rehydrate a package of dry yeast and throw that in to finish the beer, and definitely use this pitching calculator next time for working out how big a starter you need.