Adding mroe yeast after long Lagering?

My last lager batch was Lagered for 2 months at 4 degrees C. I used Beersmith 2 to calculate the amount of priming sugar to give me 2.6 Vols of CO2 and primed. 6 weeks later and the beer is great, but to me is well under carbonated - more like 1.8 or 1.9 volumes of CO2 if I were to take a guess.

Is it possible that the lagering process is resulting in the yeast being less effective in eating the priming sugar to give me the right level of carbonation? I currently have a few other batches lagering that I plan to bottle at the end of July and need some advice on what I should be doing to ensure that I get the right level of carbonation in my bottled beer? Any advice welcome.

I use this priming sugar calculator.

http://www.northernbrewer.com/learn/resources/priming-sugar-calculator/

You should be weighing your priming sugar and not measuring.

You want to use the warmest temperature the beer has been at. Not the current temperature the beer is at. So if you did a Diacetyl rest at 65 degrees than that would be the temperature you put in the priming sugar calculator.

That said, I have noticed that with my lagers I usually prime to 3 volumes and it comes out about right even though they are supposed to be primed at a lower rate. You may have to do some adjusting similar to what I do.


I have also started rehydrating a few grams of champagne yeast at bottling to ensure I get good timely bottle conditioning.

Yes, it's quite possible that the yeast is sluggish after lagering.

It should still carb up (assuming you used about 4 ounces of priming sugar) but it might be slow.

What many people do (including me) is add about 1/3 package of dry ale yeast to the cooled priming solution when bottling lagers. You don't need more than about 3 grams, and once the priming solution is cooled to under 80 degrees, you just stir that yeast in and then rack the beer into it. It ensures even and quicker carbonation.