Issues with Lagers & Pilsners

I have brewed multiple beers with cold-fermenting yeast strains, most recently a Maibock, Czech Pils, and a hoppy pilsner. In each case, I have followed the practice of fermenting at 52 degrees (using a chest freezer with a temperature controller) and then doing a diacetyl rest with 20-25% fermentables remaining. My rests are usually 2-3 days, and I cold crash after confirming that gravity is stable.

At each reading, I taste the sample after measuring the gravity. What I have noticed is that the hops flavor diminishes quickly over this short time, and after lagering for two months, the final beer has little hoppiness but a predominant sweetness that I would almost liken to malt liquor (although it's been over 20 years since I've tasted malt liquor). The flavor is definitely not diacetyl, and I doubt that the problem is that I'm crashing too soon - my final gravity readings have been in the 1.010-1.012 range. Can anyone think of what might be responsible for this [off] flavor?

 

Maybe dms? Do you 90 min boil or chill with the lid on? Hop flavor tends to be one of the first characteristics to age out for me, and I'm wondering if as this happens, it's allowing the off flavor to show through more.

 

Depending on what the recipe calls for - some of these recipes have been 60 minutes whereas others specify 90 minute boils.

 

DMS. Could be your boil time. As for hop aroma, it's going to fade as you lager.

 

Does the sweetness clear out with a little time? I've had one that did this, my German Pilsner that was super sweet tasting for about 3 weeks in the bottle and then cleaned up.

It wasn't DMS or diacetyl. Not sure what exactly.

As for hop chracter, it can die out pretty quickly.

It does sound like you are lagering too soon. I don't often to gravity measurements part way through, but my lagers go through about 10 days at 50F, then a 2 day rest and then 2 weeks at 38F before bottling. Nice and clean. I haven't done any hoppy varieties yet, but they've almost all come out great. The Pilsner is the only one that was off at first.

What hop varieties are you using? What kind of IBUs? My German Pilsner at 38IBU is very mild. Then again, it could be the noble hops are just clean and light in general. I do notice the hops, but more mild than most ales with a similar gravity in the high 30IBU range.

 

I'm thinking DMS or acetaldehyde (cidery). Maybe you need to either a) aerate your wort better, b) pitch more yeast or c) do both.

 

Interesting, I was feeling a bit disappointed by this summers batch of lagers and light ales. All seemed to be lacking something in the hop flavor, all are tried and true recipes I've done for years. I quickly brushed it off as being due to the "hoptimus rex" brand hops which I've never used before. Was planning to go back to hop union next brew season.

 

Post your recipe.

Maybe you just need more hops knowing they are going to fade as the beer ages.

 

Could it possibly be oxidation? I perceive that as a honey flavor (in fact it tastes exactly like honey malt to me). Seems unlikely, but it seems to fit here.

 

Post your recipe.

Maibock:
13 lbs. German Pilsner
.5 lbs. Carahell

Mash @ 152° F for 60 minutes
1 oz German Perle (60 min)
1 oz. Hersbrucker (60 min)
1 oz. Hersbrucker (15 min)
Wyeast 2124 Bohemian Lager Yeast

Czech Pilsner:
9.5 lbs. German Pilsner
.25 lbs. Carahell

Mash @ 151° F for 60 minutes
1 oz German Perle (60 min)
1 oz. Saaz (30 min)
1 oz. Saaz (15 min)
Wyeast 2278 Czech Pils