Sorry ahead of time for the long post. I've been homebrewing for over a decade now, always ales, and have within the past few years begun to try my hand at lagers. Out of the dozens of brews I've made, I've yet to brew a successful lager. At first I was having huge issues with diacetyl and oxidized wort. Through tweaking my process, I feel like I've eliminated these issues, or at least reduced them to where they are not as pronounced. Recently I tried to brew a Festbier. I thought it tasted fine after performing a diacetyl rest, and went to lager it in a keg. As I began to draw samples, I noticed the beer had a distinct taste to it, but I couldn't put my finger on it. I know its not diacetyl as there is no "butter" taste and no slickness on the tongue. The finish is actually very clean. I also don't detect any wet cardboard or sherry like flavors, so I don't believe its oxidized. I then allowed my wife to try it, as she can sometimes detect things better than I can. She liked the beer, stating it had a honey aroma and strong caramel flavor. Since this is NOT what this beer is supposed to taste like, I Googled these characteristics and found that they can be caused by Pentanedione, which is created just like diacetyl. I searched for causes of this, and a possible solution, but came up mostly empty handed. I've seen posts where other brewers have mentioned having the same issue, but no one seems to know the solution. I further read that a diacetyl rest will not assist in the removal of Pentanedione. I even read one post where someone mentioned it will fade after several months of lagering, but honestly I don't want to tie up my brewing for months and hope that a possible bad batch will get any better. Anyone have any experience with this, or know where the flaw is that's creating it. Not enough yeast, water profile, fermentation temperature, oxidation somehow? I used to cool my wort overnight, but recently began cooling it faster and being able to pitch the yeast and aerate the wort within several hours rather than overnight. This hasn't really helped, so I'm stumped. Any help would be appreciated. Thanks!