Krausening to rid of diacetyl

I recently brewed my first lager, a Vienna, and it's kind of a diacetyl bomb. I raised the temp for a diacetyl rest about 7 days after fermentation kicked in, and am now being told that was too soon. One guy in my club suggested I make a small starter with any lager yeast and pitch it at high kruasen, and that should get rid of the diaceyl. Anyone have any experience, or thoughts on this method? What temp should I do that at?

I am really (but not really) surprised that no one has replied to you on this.

I think it wa probably premature for you to do a diacetyl rest so soon also especially since it's a lager...it was probably not done fermenting yet.

If you've already added the extra yeast then just let it ferment out. After the brew is done fermenting (the projected FG is reached) then it's time for the DR. In which case you would let the brew come to room temp (about 70) for a couple of days. This will allow the yeast to clean up after itself and eat up any diacetyl.

Lagers usually take longer to ferment since the temp is so low.

After that it's time to bottle/keg.

Thanks for the response. Everything I had read (granted, it wasn't much) was to do the rest 75% through fermentation. So I did. Oh well, live and learn. I just pitched a 1/2 gallon active starter with saflager yeast in to the keg last night so we'll see what happens. I'll post results.

It worked to a degree. It certainly reduced the amound of diacetyl a lot, but it's still present, mostly in the nose. I'm pretty pleased with the results, though, and would recommend them to anyone looking for a similar solution.

I have the same problem with a Czech pilsner I recently brewed. It's racked and lagering now, but it's also a diacetyl bomb. I've thought about putting together a 2L starter (extra light DME and lager yeast), letting it get to high krausen, and pitching it in the secondary. Then leaving it lager for a month prior to bottling. I've heard that krausening is typically done with 20% of the total volume (5.5 gals. volume means 1 gal. of starter), but that's for carbonation. I wonder if I need as much just to clean up the diacetyl.

jgourd said:

I have the same problem with a Czech pilsner I recently brewed. It's racked and lagering now, but it's also a diacetyl bomb. I've thought about putting together a 2L starter (extra light DME and lager yeast), letting it get to high krausen, and pitching it in the secondary. Then leaving it lager for a month prior to bottling. I've heard that krausening is typically done with 20% of the total volume (5.5 gals. volume means 1 gal. of starter), but that's for carbonation. I wonder if I need as much just to clean up the diacetyl.

Click to expand...

I split 1 qt starter with W34/70 at high krausen between two batches with good results. Definitely cleans it up