Off Flavors - Why Does Yeast Hate Me?

I've brewed for years with pretty good results, but my last two pilsners have been VERY yeasty. Something's wrong and I don't know what. Using Wyeast Czech Pils yeast, (new packets;-not re-pitching) fermenting at 41F degrees. Waiting two weeks in secondary before bottling, then 4 weeks in the bottle. Still tastes yeasty like a wheat beer. Not at all what a czech pils should be.

I'm missing something simple. Can anyone put me back on the path to great beer?

How long did you leave it in primary? I don't have any experience with lagers but I do know that a few weeks in the fridge can dramatically decrease "yeasty" flavors. Try lagering the bottles for a month or so and see if that makes a difference.

The first thing that jumped out at me is the fermentation temperature- you're about 10 degrees too cold for the yeast to work at its best. Heres the info from Wyeast's site:

Classic pilsner strain from the home of pilsners for a dry, but malty finish. The perfect choice for pilsners and all malt beers. Sulfur produced during fermentation can be reduced with warmer fermentation temperatures (58°F) and will dissipate with conditioning.

Origin:
Flocculation: Medium-High
Attenuation: 70-74%
Temperature Range: 50-58F, 10-14C
Alcohol Tolerance: 9% ABV

As you can see, you're way below the temperature range. I'm surprised it ferments very well at that temperature.

When I make lagers, I ferment them for about 10 days to 14 days in primary, check the SG, and do a diacetyl rest if needed. Then rack to secondary, and start the lagering, usually at 34 degrees for 8-12 weeks. But the lagering can be done warmer (like at 41 degrees) if you don't mind a not-quite-as-crisp result.

What have your OG and FGs been like?

Also, don't forget that lagers usually require a BIG starter- here's the pitching calculator from mrmalty.com to help you decide what sized starter you need for your lager, based on the OG:

Mr Malty Pitching Rate Calculator

Well, the first thing I'd look at is your fermenting temps. 41 degrees is pretty low, even for a lager. Wyeast suggests a temperature range of 50-58 degrees, and you're 9 degrees under the low end. 41 is just about lagering temperature.

Then I'd ask what kind of starter/pitching rate are you using? Common consensus is that the lower the temps, the bigger the starter you need. Pushing the envelope at the low end, we're talking liters worth of starters.

How long is your primary fermentation? Are you hitting your desired FG? What temps are you doing your secondary at? What's your recipe?

Just throwing a bunch of questions out there.

Chris

Ah, I type to slow. Brewing Goddess Yooper beat me to it!

My OG is 1.051 with a 1.015 final. Since the yeast is still active (but super slow) during lager, I never really thought that fermenting at 41F would be an issue. Do you think that's it? I've made nice crisp pilsners before, following the same routine. It could be that I just got lucky before, and now I'm paying my dues?

Batman said:

My OG is 1.051 with a 1.015 final. Since the yeast is still active (but super slow) during lager, I never really thought that fermenting at 41F would be an issue. Do you think that's it? I've made nice crisp pilsners before, following the same routine. It could be that I just got lucky before, and now I'm paying my dues?

Click to expand...

maybe. Or maybe the active fermentation warmed up the liquid enough to be at a perfect temperature, or maybe you used a different yeast strain, or maybe you had more yeast cells you pitched.

I really think 41 is cold- especially if you have it someplace like a basement floor where the concrete is really colder than that.

I think if you ferment in the 50s, then lager at 41 (or lower) for a longer time than two weeks, your yeasty flavors will be gone.

I'm going to jump on the "how long did you leave it in primary before racking?" bandwagon as well...

I'm with everyone else, too. Warm up your fermentation, and extend your lagering time. For lagers, I tend to go 2 weeks in the primary, usually about 2-3 weeks or so in a secondary, then keg and lager for at least a month (usually more like 2 or 3). I'll check for diacetyl when racking to the secondary.


TL

Primary is typically between 10-14 days. Sounds like I should wait longer. The CO2 production tells me when to go to 2ndary - no more bubbles in the air lock is what I look for. Secondary length is a bit different. Usually 3 weeks, but it's been a lot longer if I get busy and don't get to it. Do you think that I went to secondary to early and that's causing the off flavor? I thought the yeast would still do what it's supposed to, even if I rack too early. This could be the key thing I'm missing in my brewing - a better understanding of how critical the primary ferment time is, and understanding when to rack to secondary.

Problem solved. Many batches / tests later.... My pitch rate was waaaaay too low. Brewing quality beer again.