Diacetyl during lagering

[paraordnance]

This is something new to me since I never delt with diacetyl before. Brewed my first pilsner few weeks ago with Wyeast 2001 Pilsner Urquell, fermented for 14 days, pulled a sample @ 1.020, could not taste any popcorn/butter, sample was clean and smooth but decided what a heck, will give it diacetyl rest anyway. Left it at room temp for couple days, than transfered to secondary and left it to lager in fridge for couple weeks. Just pulled a sample last night and it was really bad. Not sure if it's diacetyl or what? Kind of solvently/oily type of taste, doesn't reminds beer at all. Could diacetyl developed during lagering phase? It was great beer before I swear. Is it a dumper or I just need to warm it up for couple days? Could be infection I guess too but looks clear on top. Most of the yeast has settled but some still in suspension, whats my options?

 

[WildGingerBrewing]

bump. My first lager just finished the D-rest and I am dropping the temp slowly now.

 

[paraordnance]

Should I rouse the remaining yeast in secondary carboy and leave it at room temperature for couple days? I think nothing can hurt it now, I either try to salvage batch or dump it eventually

 

[WildGingerBrewing]

Obviously I'm no expert but that's what I would try.

I didn't rack mine to a secondary. IAfter 10 days in primary at 52F, I set it out and let it come up to 64F for 2 days then put it back in the fridge. I will slowly drop the temp by 5 degrees every day until I get it as cold as possible and then leave it for 3-4 weeks.

 

[indianaroller]

Diacetyl is characterized by a sweet artifical butter flavor that gives beer a fuller mouthfeel. That does not sound like what you have but solvent/oily is not a great description. Does it have an oily texture or does it taste like oil and what kind?

 

[paraordnance]

Obviously I'm no expert but that's what I would try.

I didn't rack mine to a secondary. IAfter 10 days in primary at 52F, I set it out and let it come up to 64F for 2 days then put it back in the fridge. I will slowly drop the temp by 5 degrees every day until I get it as cold as possible and then leave it for 3-4 weeks.

are you planning to lager it on yeast cake in primary? Thats not a very good idea I think.

 

[paraordnance]

Diacetyl is characterized by a sweet artifical butter flavor that gives beer a fuller mouthfeel. That does not sound like what you have but solvent/oily is not a great description. Does it have an oily texture or does it taste like oil and what kind?

I'm not sure to be honest. I never taste anything like that, I have to try it again today and report back

 

[WildGingerBrewing]

I didn't plan on racking to secondary. I have pretty much quit using secondary unless I am dry hopping or adding fruit, etc... If it was going to be a long period of time I would probably do it, but since it's only a couple of weeks, I didn't think it would hurt. I usually primary for almost that long anyway. Anyone know one way or the other?

 

[Catt22]

IMO, it takes longer than a couple of days at room temperature to do a proper diacetyl rest. It will require a day or so for the fermenter to first warm up, then you need to hold it at 65-68*F for two or three days longer before dropping to lagering temps. It's best to start the diacetyl rest slightly before the beer has completely finished out.

I'm not convinced that what you are tasting is diacetyl. I would get a second opinion from another brewer if possible before taking any action.

 

[Dawgs47]

I was listening to a Podcast on Lagering yesterday and I thought they said to allow the first stage of fermentation to complete before raising them temp for the diacetyl rest, which would increase the clean up stage of fermentation. So I think you should have keep it cool until you reached your FG, then raise the temp to increase the clean up of the flavor, then cold store.

 

[Catt22]

I was listening to a Podcast on Lagering yesterday and I thought they said to allow the first stage of fermentation to complete before raising them temp for the diacetyl rest, which would increase the clean up stage of fermentation. So I think you should have keep it cool until you reached your FG, then raise the temp to increase the clean up of the flavor, then cold store.

Palmer, in his book, "How To Brew", 2nd edition, page 122 he recommends racking to a secondary when the beer is 3/4 of the way to terminal gravity. He also states that if you let the beer completely finish out, you will have missed the opportunity for a diacetyl rest. I don't necessarily agree with this and IIRC, neither does Noonan in "New Brewing Lager Beer". FWIW, I've done it both ways and cannot discern any difference. Recently, I've been going with Palmer's method letting the beer almost, but not quite finish out, but I do the diacetyl rest in the primary on the yeast cake and not in the secondary. I begin lagering only after I rack to the secondary. My thinking is that allowing the temperature to rise before the krausen has dropped helps the yeast consume the last bit of fermentables and accomplishes the diacetyl rest at the same time. The bottom line seems to be that there are varying opinions on what is the best approach, but as I said, I've gotten excellent results doing it both ways and with some variations on each method. I've come to the conclusion that it doesn't matter which way you do the diacetyl rest. I do one whether or not I detect any diacetyl presence just as insurance figuring it can't do any harm and apparently it doesn't.

 

[sdillow]

Do you slowly bring the fermenter up to room temperature for the diacetyl rest, and if so, what increments? I'm fermenting at roughly 55 and plan on starting the rest when it's maybe 4-5 points shy of FG.

 

[Catt22]

Do you slowly bring the fermenter up to room temperature for the diacetyl rest, and if so, what increments? I'm fermenting at roughly 55 and plan on starting the rest when it's maybe 4-5 points shy of FG.

Yes, sort of. I let my lagers finish out a little beyond what Palmer suggests. Typically I wait until I only see about one bubble per minute out of the air lock or even a little less than that. I turn up the controller setting to 68*F if the ambient temps are relatively cool, but when it's hot in my garage I do it incrementally at about 4*F per day or so. It's not all that critical IMO and sometimes I forget to make the daily adjustments. Often my diacetyl rests extend to a week or so before I rack and begin lagering. I think your plan is good and it seems to be in line with what Palmer recommends. IMO, it would be very difficult to screw this up no matter how you do it. Obviously, it might not be good to keep the beer at very warm temperatures for very long periods, but I don't think any of us would go there anyway, so it's a moot point.