lager fermentation problem

[bionicbrew]

well, i'm stuck. or my beer fermentation seems to be. i brewed a Munich Dunkel 2 weeks ago. i did a partial mash, but it dropped 18*, so it was more of a soak. 158* down to 140* over 60 mins. I didn't expect much out of the mash anyway besides some color. everything else went to plan. 7lbs of amber syrup and 1 lb of wheat syrup(left over from a previous brew the week before). I hit 1.050 for the OG. pitched it at 66* with Wyeast 2206-Bavarian lager. package didn't rise as much as it probably should have. it's been sitting at 52* for the last 2 weeks and is now 1.047.

any suggestions on how to diagnose if i just need to pitch with more yeast, or if something else is going on? it looks like yeast is making a cake on the bottom and some sticking to the low sides of the fermenter. i made this beer many years ago and it was excellent and no problems. i did have an ale a few years ago that did this, but was a high gravity doppel bock.

thanks for any help.

 

[Yooper]

How many packages of yeast did you pitch? Or did you do a starter?

 

[bionicbrew]

i used the 125ml pack. one of them.

 

[Yooper]

That's an issue, but if it fermented a little, there must have been some yeast reproduction going on. Or, maybe the OG when it's temperature corrected is exactly the same.

At this point, I'd buy another package of yeast and make the correct sized starter (consult mrmalty.com for the exact pitching rate, but it looks like depending on yeast age, a 12L starter would be appropriate). A 1.050 lager calls for 350 billion yeast cells, and there are 100 billion in one package. Alternately, you could buy three packages and throw them in there.

If your sanitation was good, there shouldn't be any reason why repitching wouldn't work.

 

[bionicbrew]

I did temp correct the gravities. of course those 2 #'s are very close and variation could occur. i'll try the repitching.
what could cause non fermentation in the sanitation department? i've had very few problems over the last many years, but i know it can happen anytime. thanks for your help!

 

[petep1980]

I have had some slow ass ferments with some older wyeast lager yeast packs recently. Once I couldn't even get the starter started.

Your pitch rate was obviously too low (I did this too once), so you'll need to step up a starter or pitch a couple packs. Don't worry though as long as you maintain sanitation pitching late isn't going to kill you.

 

[bionicbrew]

well, thanks again for the suggestions. i went to my LHBS and they didn't have the yeast i wanted, or much for good substitutes, but i found something i can live with. of course they only sell the little 50ml propagator packs. i did a 2 step starter to try and boost it as much as possible. and today after about 12 hours there is a nice big foam head in the fermenter! whew!

 

[michael.berta]

Good job! The lesson learned here is that you way under pitched. Using the pitching rate calculator from now on would be a great idea.

Mr Malty Pitching Rate Calculator