Help with light lager - Strange taste after bottling (Acetaldehyde?)

Hello,

I usually do ales without any problems. But this time, I brewed a light lager (75% 2-row + 25% flaked corn, 12 IBU hallertau at 60 minutes). Fermented at 50F for 3 weeks with WLP-940 Mexican lager, no starter 1 vial for 2 gallons of beer. It tasted really nice before bottling (I was planning to do the lagering in bottles). I did not add new yeast prior bottling.

After 1 week of bottle condition (at 66F), not a lot of carbonation, sulfur taste (the fermentation wasn't complete).

After 2 weeks in bottles (at 66F), good carbonation but a strange green/herbal taste at the end. Is it acetaldehyde?

I have never had this problem with my ales in 10 years. Is it specific to lager yeast?

For now, I stated the lagering phase with some bottles (35F) and the other bottles are kept at room temperature (66F).

Is it possible to do a good bottle carbonated lager?

Any advice?

Thanks!

Sam

Of course it's possible, your beer just isn't ready yet. As Revvy will doubtless materialize to tell you, three weeks is the low end of the carb + condition time spectrum. It will often take longer. Leave it alone for another month, and then if necessary re-lager them right in the bottles... and by that I mean, stick them in the fridge for a few weeks.

Kerin, you were right! I had 3 sets of bottles:

A - Kept in cold (33F) : the green apple taste never went away
B - Room temperature (65F) : the green apple taste faded (50% less)
C - Warm temperature (75F) : the green apple taste went away

Next time, I'll make sure to condition my lagers at warmer temperature and for a longer time (3+ weeks).

Thanks again!

Sam

Not a problem. It's actually an easy mistake to make if you lager in the bottles, which isn't uncommon: if you do this, you have to make sure to take them back out of the fridge for a few weeks before you chill to serve.

For my one lager this year (my re-birth to brewing year), I lagered in the secondary at 34*F and then left in the bottles for 5 weeks at room temperature. Once that was done they were pretty damned good if I may say so myself. There were some off flavors, but I attribute that to the water mostly.