Diacetyl/chemical flavours

[onelegout]

Hi,
I've been having problems with my all-grain batches. it seems that I get off flavours from them and not from extract batches!
I've used different hops, grains from different suppliers, different yeast strains, and I still get the same flavours: green apple/chemical taste/strong butter taste from my all-grain batches despite performing week-long diacetyl rests! Could this be infection? When I've hit my FG and it's been stable for 3 days does that mean fermentation is definitely over and waiting say, 4 days for diacetyl to be reabsorbed will be fine?
I cant see where I'm going wrong

 

[menschmaschine]

What kind of yeast are you using? Are you brewing lagers? Diacetyl rests are usually only recommended for lagers. If done, they need to be done before primary fermentation has ended, i.e. when it's winding down you raise the temp.

How many AG batches have you done that had these off-flavors? You describe three different off-flavors that could have 3 different sources. Have you seen Palmer's page on off-flavors? He describes where they can come from.

 

[Revvy]

At what point in the process are you detecting these flavors? Are you noticing them while sampling in the fermenter, or in the bottle under 3 weeks...or longer than that?

It is really difficult to figure out whether you truly have an off flavor, UNTIL it's been over 3 to 6 weeks in the bottle (or kegged) there is too many processes that that beer still have to go through, which will change the flavor (mostly cleaning up stuff like that) which won't be complete till the beer is carbed and conditioned...otherwise the beer could just be green and young...

Most of my AG beers taste grainy and somewhat nasty until the condition.

As to d-rests, this is a good thread...I even posted some stuff at the end on D-rests for ALES as well as lagers. https://www.homebrewtalk.com/f13/preventing-diacetyl-hold-butter-please-70438/

But if your beer is 8 weeks in the bottle and taste that way, then you could concerned, anytime before that, for me, I would just feel that the issue was greeness and give it more time.

 

[onelegout]

Hi guys,

Thanks for the advice. I am detecting these flavours after 10 days in primary, in a weissbier. The reason I am concerned, is my last two AG batches (an ESB and ordinary bitter) have both had the same off-flavours, which have remained in the beer even after 2 weeks secondary and 1.5 months in the bottle.

For this latest batch I'm using Weihenstephan Weizen (wyeast #3068), but I've been disappointed to find absolutely no trace of clove or banana esters in the beer after primary.

I just decided that regardless of the off-flavours, the beer was not nearly as flavoursome as I had hoped (I was going for high clove and banana esters/flavours) so I just boiled the flesh of 5 bananas with 15 cloves and two cardamom pods, cooled them and added them to the primary! I also added a dry hop addition of a very small amount of Hallertauer Hersbrucker hops (2.1%AA) and will leave for a further 3 days before bottling half the batch and kegging the other half.

How long would you recommend leaving the kegged batch before serving for a weiss?