did a diacetyl rest and still buttery

Did some searching but didn't a great answer so here it goes...
Brewed a lager, everything went great. OG was 1.058 threw it in the fridge at about 48 and krausen was formed by the next morning. Fermented in the fridge for 2 weeks and then pulled out for a diacetyl rest at 66-72ish left it for about 2 1/2 days took a gravity, 1.015 and it tasted good, maybe a slight buttery taste but not bad and since the gravity was pretty close to FG i transfered to the lager keg and cooled to about 40. that was about 2 weeks ago.

Anyway just tried a sample last night and it seems to have a stronger buttery flavor, should i let it finish lagering or take another course of action? I saved the yeast for the next lager, its wyeast 2053 and is in a bottle in the fridge so i could add a bit of that and hope it cleans it up. just a thought, thanks in advance!!

Let the carbed keg sit at room temperature for a week or two?

Kraeusen it. Make a ~1L starter and add it to the keg once it starts fermenting.

cool, i'll try moving it to room temp for a bit and try it, if its still buttery then i'll pitch some more yeast. It helps i have the yeast that came from this batch. I'm stumped how it got the diacetyl taste as it started fermenting cold and I did a rest and the gravity seems about right

I've had the same problem with a couple of my lagers. Krausening works. I've heard that small amounts of oxidation during transfer from fermenter to keg can cause diacetyl precursors to convert to diacetyl. The result is the presence of diacetyl in the keg/bottle that was not in the fermenter.

Do what 944 said; also for future reference you want to do your d-rest when SG is about 8-10 points above target FG. Your yeast must still be active for your d-rest to be effective. It's too late once you hit FG. Your hydrometer, not your calendar, is your guide for when it's time for a d-rest.

My experience fixing diacetyl: https://www.homebrewtalk.com/f14/will-work-205761/

out of 6 lagers I brewed 5 had diacetyl showed up in a keg after lagering. Including my last batch of pilsner which sits right now for over a week @ room temp and diacetyl almost gone completely! Krausening does work but I had mixed results from it. Before you attempt to mess with krausening I suggest you let your keg to sit at room temperature for at least a week, better two. Turn it upside down couple of times to agitate yeast. It worked for me!! I cannot believe it

I was worried that I did the rest a tad too late, Also when i transferred to the keg I carbed it and vented the oxygen out, it was only at about 3 psi. So right now its at room temp and i shook it up a bit, should i take it off the gas or leave it?

Also i tasted the beer that had separated from the yeast i collected, It didn't have a buttery taste at all. I hope the rest of it turns out that good

BierStreet said:

I was worried that I did the rest a tad too late, Also when i transferred to the keg I carbed it and vented the oxygen out, it was only at about 3 psi. So right now its at room temp and i shook it up a bit, should i take it off the gas or leave it?

Also i tasted the beer that had separated from the yeast i collected, It didn't have a buttery taste at all. I hope the rest of it turns out that good

Click to expand...

You don't want the yeast under excessive pressure. It will kill them pretty quickly and then the processing of diacetyl will grind to a hault. Pressurize enough to seat the gaskets and no more. No need to shake the keg either, whatever active yeast that's there is there.

bigbeergeek said:

You don't want the yeast under excessive pressure. It will kill them pretty quickly and then the processing of diacetyl will grind to a hault. Pressurize enough to seat the gaskets and no more. No need to shake the keg either, whatever active yeast that's there is there.

Click to expand...

pressure will not kill yeast. My keg was already fully crabed (set & forget 12 psi) when I discovered diacetyl in keg. All I did is pulled keg out of freezer and left at room temperature shaking it once in a while to resuspend yeast. It worked. I just placed that keg back to serving freezer, no more diacetyl

paraordnance said:

pressure will not kill yeast.

Click to expand...

According to the seminal book Yeast by Chris White (of White Labs Yeast) and Jamil Zainasheff (one of the most notable homebrewers of our time), pressure does kill yeast.

Pg. 157: "...pressures as low as 20 pounds per square inch can prove fatal to yeast."

20 psi might be a bit higher than normal for a regulator on a homebrew keg, but if the yeast are active and the keg is shaken, more pressure could build up in a room temperature free-standing keg. I would vent off pressure and keep the yeast unstressed to clean up the beer.

In the future, to really check for diacetyl (usually before reaching FG as above) you should heat a small sample of it and then smell it. There are several posts about testing for diacetyl this way on this site. If you have diacetyl in the beer, there will be no hiding it after running this test.

bigbeergeek said:

According to the seminal book Yeast by Chris White (of White Labs Yeast) and Jamil Zainasheff (one of the most notable homebrewers of our time), pressure does kill yeast.

Pg. 157: "...pressures as low as 20 pounds per square inch can prove fatal to yeast."

20 psi might be a bit higher than normal for a regulator on a homebrew keg, but if the yeast are active and the keg is shaken, more pressure could build up in a room temperature free-standing keg. I would vent off pressure and keep the yeast unstressed to clean up the beer.

Click to expand...

I meant the pressure we usually deal with. Never seen my yeast die in already carbed kegs. Obviously anything will die at 5000 psi

I originally had pressurized the keg to force the oxygen out, then i turned off the gas. I Carbed it to 3ish psi just to test taste it and thats when i noticed the diacetyl. Now it sits at room temp with no gas, i'll leave it for a week or so and hope it does the trick. Thanks for all the replies, It almost seems that you could ferment two batches the exact same (yeast, temp, time) and one would have diacetyl and the other one wouldn't

ayoungrad said:

In the future, to really check for diacetyl (usually before reaching FG as above) you should heat a small sample of it and then smell it. There are several posts about testing for diacetyl this way on this site. If you have diacetyl in the beer, there will be no hiding it after running this test.

Click to expand...

Ditto. Use a forced-diacetyl test to see whether you have precursors in your beer.

Take a sample of beer (w/ ales, before you crash them; lagers, use the earlier poster's goal of making sure you rest before your yeast goes totally dormant) and:

1. pour it back and forth between two cups to oxygenate and decarbonate the beer.
2. pour it into a bottle and shake it up. the goal here is to provide plenty of O2 to oxidize the beer and covert the vicinal diketone precursors into diacetyl if they are there.
3. heat it in a water bath for about 90 minutes at 130 degrees F. then let it cool and taste. you're looking for that butterscotch smell/taste.

Just an update, I left the keg at room temp for about 8 days then put it back in the fridge at about 40 to lager, I tried a taste the other day and it is much improved!! still has a little of the buttery smell but its not really in the taste. thanks for the suggestions