We have brewed a number of ales, but recently tried our hand at a pilsner.
After 8 days of fermenting at around 52 degrees F, we brought the pilsner up for a 2-day diacetyl rest at around 68 degrees. At this point we proved our inexperience by moving the carboy back into the cooler to crash without racking over. Unsurprisingly, we discovered off flavors, most notably strong diacetyl, when we were preparing to rack over into kegs to serve.
What would be the impact of bringing the carboys up for a second d-rest at this stage?
Will the yeast have enough left in them to dispose of the diacetyl? Are we inviting autolysis?
Any suggestions to salvage the beer?
We are trying to avoid repitching yeast, but if that's the only way, we're open.
Another technique we've read about is bubbling CO2 through the beer and purging the gas repeatedly. Has anyone tried this?