Pilsener Help!

[Hops-and-Dreams]

Ok...I brewed a Pilsener on Feb 1. The Pilsener yeast called for 50-55 degree fermentation temps. So I tucked the carboy in the back room that has no heating vent so it was nice and cold. Over the month the average temp of the room was actually below 50, sometimes even close to 40. I know that fermentation will continue albeit at a much slower rate. But I was told to let it ferment for 4 weeks then let it rest for a minimum of 6 weeks before bottling or kegging. Well the temp is now coming up and the Pilsener is showing signs of life again. The airlock is going about 3 times per minute which means it's still fermenting...so how long can/should I keep it on the yeast? It has been 5 weeks since I brewed and pitched the yeast. Yeast is White Labs Pilsener Lager Yeast WLP800.

 

[JonM]

Have you taken a hydrometer reading?

Also, did you use a starter with that yeast?

 

[RM-MN]

Ok...I brewed a Pilsener on Feb 1. The Pilsener yeast called for 50-55 degree fermentation temps. So I tucked the carboy in the back room that has no heating vent so it was nice and cold. Over the month the average temp of the room was actually below 50, sometimes even close to 40. I know that fermentation will continue albeit at a much slower rate. But I was told to let it ferment for 4 weeks then let it rest for a minimum of 6 weeks before bottling or kegging. Well the temp is now coming up and the Pilsener is showing signs of life again. The airlock is going about 3 times per minute which means it's still fermenting...so how long can/should I keep it on the yeast? It has been 5 weeks since I brewed and pitched the yeast. Yeast is White Labs Pilsener Lager Yeast WLP800.

I don't do lagers so take this advice for what it is but a brewer that I converse with said he kept an ale in the fermenter for 8 months with no ill effects. Being kept cooler, I would suspect that a lager could go even longer.

With the temperature rising, your airlock may be fooling you because your beer cannot hold as much CO2 and that coming out of suspension in your beer may be making your airlock bubble. Airlocks are nothing but a method to vent excess gas and should not be taken as a proof of fermentation. Use your hydrometer. Sample today, sample next Wednesday and if the readings match, fermentation it over.

 

[Hops-and-Dreams]

Have you taken a hydrometer reading?

Also, did you use a starter with that yeast?

I have not taken a hydrometer reading since pitching...and yes, used a starter yeast.

 

[Yooper]

I have not taken a hydrometer reading since pitching...and yes, used a starter yeast.

Grab a hydrometer reading. Some lager yeast strains will go dormant below about 48 degrees, so you may have had a stalled fermentation that is now starting up, or maybe not. No way to know without a reading.

 

[duboman]

Grab a hydrometer reading. Some lager yeast strains will go dormant below about 48 degrees, so you may have had a stalled fermentation that is now starting up, or maybe not. No way to know without a reading.

+1
If the hydrometer reading is close to what you expect it to finish at you can let it warm up for a D-rest and let it simply finish, then crash it to near freezing to lager a few weeks

 

[Hops-and-Dreams]

So I took a hydrometer reading and it was at 1.016. My target is 1.012. Leaving it on the cake for another week won't hurt right? Then I will transfer and let it rest for a while. I was told 4 weeks fermentation then a minimum of 6 weeks resting, but I will be at 6 weeks on the cake so do I still need 6 weeks of rest after transfer? Should I wait longer than the 6 weeks? What is the general recommendation?

 

[McKnuckle]

I would warm it up a bit to the low 60s for a couple of days if possible to encourage the yeast to finish and clean up any diacetyl. Then cold crash near freezing, rack to secondary once it looks clear, and keep in that cold environment as long as you can stand it. If you keg you can use the keg as your secondary/lagering/serving vessel all at the same time, and carbonate while you lager. Otherwise, lager in the secondary as just stated.

After 4-6 weeks*, bottle with priming sugar, and move the bottles to a 70F environment for about 4 more weeks to carbonate.

*This is recommended, but if you cheat and sample sooner, it will still be good! You can save the extended lagering for the bottles once they are carbed up. The flavor and mouthfeel do change for the better with longer time in the cold, but it's not like night and day IMHO.