Sorry for all the detail but this one one has me frustrated.
I am having repeat problems with very slow and inconsistent carbonation of my big beers. By big beers, I mean barleywines, imperial stouts, and triples. All are over 9% abv. I’ve never had a problem with lower abv beers such as IPA’s, pale ales, etc all under 7% abv.
I made a barleywine and RIS late last year. I bottled them both in February with a fresh pitch of Danstar Nottingham. I sampled both of these batches at 4 months, flat. I rolled all the bottles to redisperse the yeast, and moved them warmer area, 70F +. Over the weekend I sampled them, 6 months in the bottle. Both had just a little pressure but nowhere near carb’d. I expect the big beers to take longer to carb but in 6 months, they should be there. At this rate, it would take another year to carb them so I decided to re-yeast with Danstar CBC-1.
As I opened them, I found about the same results in both batches. At room temperature: 2-3 bottles fully carb’d, 4-5 very slight slight carbonation, and the balance were flat.
I’ve had the same problem with previous batches of barleywine, imperial porter, and imperial stout. I’ve had very slow carbonation with the triples but generally they carb up in 3-4 months. I do have have a few bottles from each batch which are flat.
Here’s what I am doing:
I use Danstar Nottingham for the barleywine and RIS. I used fresh trappist high gravity yeast for the triples. I rehydrate dry yeast before bottling.
I don’t repitch when bottling the lower abv beers.
I am visually inspect the bottles.
I spray the bottles with star san solution and then use the sanitize cycle in the dishwasher.
I stir the bottling bucket after every 6 beers to disperse the sugars and keep the yeast in suspension.
I use brewers best bottle caps soaked in star san solution.
Once all the bottles are filled I lay the caps on the bottles, then clean the area.
I use a hand capper to seal the caps about 60 minutes after filling.
I even consecutively numbered the bottles from the last 2 triples to see if the problems are related to the filling.
Cases are moved to the basement, with is usually in the low 60’s. (I generally brew these big beers in the winter.)
I can think of three possibilities (1) plan on a year or more to carb the big beers, (2) the nottingham strain is borderline alcohol tolerance, (3) the conditioning temp is too low immediately after bottling and the yeast doesn’t activate.
Thanks for taking the time to read this long post. I’ll be starting my ‘big beer brew cycle’ soon and want to put this one behind me.