Has anyone used this process to remove diacetyl?

[Alex4mula]

I brewed this Vienna Lager which fermented fine to FG and about 5 points before I raised the temp to 65-67F for proper Drest. Left is there one week. When I kegged it the beer tasted fine and nothing funny. But about 3 days later I took a small sample (is carbed and on tap lagering) and for the first time ever I got that butterscotch taste that brewers dread. I found this simple process to add more yeast to keg to make its magic. Has anyone done this and worked? Thanks.

Procedure: How to Fix Diacetyl - Online Beer Scores

 

[VikeMan]

Yes, that's called krausening and it does (can) work. Personally, I would try just raising the temperature first, essentially another diacetyl rest.

If you do decide to krausen it, make sure you have a way to relieve keg pressure, unless you've done the math on carbonation already present and what you'll get from the new wort.

 

[twd000]

I hate that- sample tastes great then two days later it's full on slick butterscotch candy!

Yes krausening and warmth works great. I make a little starter with some kveik yeast and set the kegs in front of my woodstove

 

[Alex4mula]

Thanks. Well, I tasted it again (with two beer buddies also) last Friday and the flavor seem to went away. I'll taste it again this next Friday. Hopefully I'll have to do nothing. Fingers crossed!

 

[Miraculix]

I hate that- sample tastes great then two days later it's full on slick butterscotch candy!

Yes krausening and warmth works great. I make a little starter with some kveik yeast and set the kegs in front of my woodstove

Whatever you do, don't use kveik for this unless you want your Vienna lager taste like a kveik.

I once brewed a Vienna lager with a starter of wlp800 that got infected with the kveik that was in the starter flask before (bad cleaning routine...). The Vienna lager tasted great first and then sloooowly changed into full blown Voss flavour after bottling, although fg was reached. Every week, the kveik take come through more and more...

Use the yeast that you fermented the net with initially.

 

[dmtaylor]

Krausening isn't needed IMO as long as the yeast wasn't filtered out. All you really need to do is warm up the beer again for a week or three, then the yeast will eat the diacetyl and it will be gone, about 90-95% of the time. Time heals a lot of stuff.

 

[Alex4mula]

As mentioned beer was transferred to keg so no more yeast. That's why I asked.

 

[VikeMan]

As mentioned beer was transferred to keg so no more yeast. That's why I asked.

There are plenty of yeast still in suspension when kegging. They're the reason your diacetyl has now disappeared (decreased to below threshold level).

 

[dmtaylor]

As mentioned beer was transferred to keg so no more yeast. That's why I asked.

As @VikeMan alluded, you actually still have billions of live cells in the beer, unless you have expensive filtration apparatus to filter them all out, and/or kill them with pasteurization. Commercial breweries sometimes do this but homebrewers rarely do.

 

[Alex4mula]

Ok. Then good because I think they did their job Thanks!