I'm keen to get hear if any of you guys have ongoing issues with Diacetyl developing in the Keg. I have this ongoing issue once the Green beer hits the keg.
This following scenario is doing my F%&^$ head in, and I really need some advise, beyond yeast selection, sterilisation and diacetyl rests.
I recently brewed a bit of an Emersons Pilsner (Ale) Clone with NZ ADM Pils Malt and 5% Caramunich 1. To this I added 100% Riwaka hops in three additions. I also used 1469 - West Yorkshire Ale yeast.
Everything seemed perfect. Premo mash, boil and fermentation hitting every target bang on. Temp control was sweat - pitching at 18C, rising to 20C over the first 3 days. I also encouraged it to rise to 22C after a week for a wee rest. The Green beer tasted f'n fantastic straight from the fermenter. Real tropical with passionfruit aroma and taste.
After a total week and a half ferment I slowly dropped it ~4C a day till I hit 1C where it sat for a few days. Then kegged it (no finings). At this point it was still fantastic and a little less yeasty. Still a bit hazy though. I then hooked up CO2 at normal despensing pressure.
Week later couldn't resist a taste. It still tasted good, but aroma seemed to be fading. It appeared to be losing its tropicalness... (I put this down to tempurature initially.)
Another week later and I couldn't smell a thing, but caramel sweatness. And the tropical, hop character was dead in the taste also. I'm a little numb to the whole Diacetyl thing but I think that is the problem masking my once great beer. The beer doesn't otherwise seem problematic.
How can this issue be developing so badly in the keg once on tap. Has anyone else had this problem? Am I not cleaning my lines enough? Should I be dismantling my kegs every time I clean them? Is my vibrating chiller having an adverse effect on the remaining yeast? Am I just going F'n nuts?
Should I try bottling some as an experimental control group...?