delboy wrote:Supposedly its better to catch it during the active fermentation stage (approx two thirds of the way to terminal gravity), but i asked a similar question not so long ago and seveneer told me that he does exactly what you are suggesting for a d-rest ie wait till its fermented then leave at a warmer temp for a few days until the diaacetyl disappears, seems to work for him.
Edit: this is what seveneer said
Personally, with my limited experience of brewing lager (2 batches), I'd have left it to get down towards 1.014-12 before going of for the diacetyl rest.
With the lagers I've brewed I didn't get diacetyl until they'd been in the lager fridge for 3-4 weeks. Then it just takes over so I take the keg out and leave it at room temperature for 2-3 days and it all clears up.
Like I said though, I've only brewed a couple of batches so not a great deal of exerience.
On the bright side you can't really taste it. I'm thinking of racking it to kegs and bringing it inside overnight for a kind of late d-rest before lagering, perhaps the agitation of the yeast and warmer temps will encourage them to absorb it? Or can this only happen during active fermentation.
