High FG.....stuck fermentation?

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Shoemaker

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Brewed ten gallons of czech pilsner, hit the target OG of 1.050. Used a 1L starter for each 5 gallons.

I think my lagering process got a little haywire. After 3-4 days at 60 degrees, I brought the wort down to 45 by putting them in the store room of my garage, which is not heated but it doesn't get too cold. However, we did have some cold days so I bet it got lower than 45.

Did a diacetyl rest at 60 degrees and checked the gravity. It was at 1.020...what the hell? FG should be at 1.010. So I stirred both carboys a bit and let them sit.

My question is, is this the right thing to do? What happens if the gravity doesn't get lower? Should I put more yeast in?
 
yea i think you may of been a little off with your lagering process. every book i've seen says to start lagering at 50F then when fermentation is nearing its end ramp it up to 60F for the diacetyl rest. after fermentation is complete crank it down to 40 for lagering.

now as for your problem the yeast may of gone dormant or flocked out because of the 45F temps. i'm sure others with more experience can give you a better idea of whats going on.
 
It also looks like you underpitched. I'd suggest checking out the pitching rate calculator.

It is really hard to fix a stuck fermentation. I've been able to get an extra 3 or 5 points with champagne yeast. I'm not sure that would be such a great idea with your pilsner though. another option is to make another starter and pitch the starter at high krausen and hope that the active starter will take care of the rest.

With lagers temperature control is very important. It should be done in a fridge with a temperature probe taped to the carboy to monitor and adjust the temperature of the fermentation. Lagers don't like to just be left out in a basement or whatever. Wild temperature fluctuations are bad. etc..

Also you may want to post the recipe, mash temperature, etc...

On the bright side you still made beer. if you are confident that fermentation is complete might rack it. You beer will still probably taste just fine. Lots of times people run around chasing numbers but if the beer tastes good that all that really matters...
 
It also looks like you underpitched. I'd suggest checking out the pitching rate calculator.

It is really hard to fix a stuck fermentation. I've been able to get an extra 3 or 5 points with champagne yeast. I'm not sure that would be such a great idea with your pilsner though. another option is to make another starter and pitch the starter at high krausen and hope that the active starter will take care of the rest.

With lagers temperature control is very important. It should be done in a fridge with a temperature probe taped to the carboy to monitor and adjust the temperature of the fermentation. Lagers don't like to just be left out in a basement or whatever. Wild temperature fluctuations are bad. etc..

Also you may want to post the recipe, mash temperature, etc...

On the bright side you still made beer. if you are confident that fermentation is complete might rack it. You beer will still probably taste just fine. Lots of times people run around chasing numbers but if the beer tastes good that all that really matters...

Thanks for the advice. I doubt I underpitched because like I said, I created a 1L starter for both carboys. I think it was the temp control. I'm going to leave it around 60 for awhile and see what happens. If the gravity gets a bit lower I'll then lager it.
 
Mr. Malty says 2.7L starter per 5gallons of 1.050 if using a stirplate. It says 4L if just intermittent shaking. You have to select "Lager" under "Fermentation Type"

From Wyeast Lager Brewing Page:
Pitch Rate:
Lagers typically have a reduced ester profile and are characterized as clean with discernable malt character. It is very important to recognize that pitch rate is directly related to ester production. Increasing the quantity of yeast pitched is the most effective method of reducing the ester profile in the finished beer. A minimum of 12 million cells per milliliter is recommended to keep esters at a minimum.

One Wyeast Activator pack will deliver about 6 million cells per milliliter to 5 gallons of wort. In order to increase this rate to 12 million cells per milliliter it is necessary to either pitch two Activators or to make a 0.5 gallon (2 liter) starter with an Activator. If a starter is made using a Propagator (50ml package) then the starter needs to be 1 gallon (3.78 liters) to achieve 12 million cells per ml.

Fermentation Temperature:
One of the most common questions we field is, “should I start my lager warm or cold?” The answer depends on how much time you have for your primary fermentation and how clean you want your final beer. The best results will be achieved by pitching at least 12 million cells per milliliter into cold and well aerated wort (48 to 58°F, 9 to 15°C).

If a faster primary fermentation is desired or you are pitching less yeast, then it is best to start a little bit warmer and then cool to the desired fermentation temperature once signs of fermentation are evident.
 
no you under pitched. 1L per 5 gallons is WAY not enough for a lager. lagers typically need 1.5 to 2 times as much yeast as an ale.
 
i think that its a temp controll, you still have a some unfermented sugar there. just add more yeast and do a better temp controll and you be ok. if you rack it in to the bottles now you will have overcarbonation in the best case, in worst case you ended up with 100+ "hand grenades".
 
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