Wed Jun 08, 2011 9:15 am
It is important that the beer contain a fair amount of yeast when it is first put down for lagering and the continued activity of those yeast in the early phases of lagering (which are resposible for the benefits) will continue to generate gas, albeit at a much reduced rate. Based on this you are more likely to have an excess pressure in the lagering vessel than to need to add gas. Gas is not necessary for lagering but it does speed it somewhat by sweeping out stinky young beer volatiles. For this reason you may wish to carbonate artificially, bleed, and then repeat.
As an example, it is my usual practice to condition in the unitank for about 3 weeks and then transfer to kegs. The kegs are filled against counter pressure so there is some pressure on the beer when the kegs go into the cooler. There they lager and the gas buildup is sufficient that the beer is nicely carbonated when it is ready. My experience has shown that in my particular way of doing things neither supplemental gas nor venting is necessary but this may not be the case for you. You really have to see what your particular process does in this regard and pressurize or not as needed.
