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!
Pentanedione Issue
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Smellyglove
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I'm having the same issues in pilsners with belgian malt. "honey", it tastes straight up like honey. It's a VDK just like Diacetyl but has a way higher flavor threshold. My impression from some reading was that if you can taste the penta then there's supposed to be diacetyl in there as well, but that's not the case for me. (Yes, I can taste Diacetyl, for instance I can't drink London Pride because of the amounts of diacetyl) I'm kind of stumped myself. Ss you mentioned, I've experienced that it goes away with a long lagering-period and the beer is wonderful. But like you, that's a long time.
Its definitely frustrating when you spend all the time for a lager and it doesn't turn out the way you were expecting. I have a few initial questions:
- What was the actual recipe that you brewed? (Maltster brands/varieties? Some are prone to these flavors)
- What was your mash and fermentation schedule? Boil intensity?
- Are you lagering under pressure (kegs)? In secondary?
- Most importantly, what yeast strain did you use and how much yeast did you pitch?
Honey and caramel to me suggest the initial stages of oxidation. These flavors, along with slight color darkening are generally the first symptoms of oxidation to appear. Wet cardboard and sherry only appear in the more severe cases. It would make sense that it only appears in your lagers, due to the extended aging time. Especially if you are not lagering under pressure (carbonated kegs).
It could be yeast derived, since it only appears in your lagers, but I would need to know more about the strain and the amount.
If it's oxidation, it's only going to get worse with extended aging. If it is something else, it could potentially get better with some time.
- What was the actual recipe that you brewed? (Maltster brands/varieties? Some are prone to these flavors)
- What was your mash and fermentation schedule? Boil intensity?
- Are you lagering under pressure (kegs)? In secondary?
- Most importantly, what yeast strain did you use and how much yeast did you pitch?
Honey and caramel to me suggest the initial stages of oxidation. These flavors, along with slight color darkening are generally the first symptoms of oxidation to appear. Wet cardboard and sherry only appear in the more severe cases. It would make sense that it only appears in your lagers, due to the extended aging time. Especially if you are not lagering under pressure (carbonated kegs).
It could be yeast derived, since it only appears in your lagers, but I would need to know more about the strain and the amount.
If it's oxidation, it's only going to get worse with extended aging. If it is something else, it could potentially get better with some time.
The recipe was as follows:
10 lbs Weyermann Pilsner
2 lb Light Munich (Avangard)
Just bittering hops
2 packs rehydrated Salager 34/70 (I've also used liquid yeast with a large starter and still had the same result)
Mashed at about 149 for 90 minutes.
Boiled vigorously for 90 minutes.
Fermented at about 53 degrees for a bit longer than a week, then once fermentation began to slow, started the diacetyl rest.
Lagering under pressure in keg.
10 lbs Weyermann Pilsner
2 lb Light Munich (Avangard)
Just bittering hops
2 packs rehydrated Salager 34/70 (I've also used liquid yeast with a large starter and still had the same result)
Mashed at about 149 for 90 minutes.
Boiled vigorously for 90 minutes.
Fermented at about 53 degrees for a bit longer than a week, then once fermentation began to slow, started the diacetyl rest.
Lagering under pressure in keg.
