Overcarbed after storage?

[7mmSTW]

Of the few batches I have made so far I've kept a few bottles to the side to taste at a later date. Seems like after 4,5,6,+ months they have gotten way overcarbed. One of these I carbed with about half a pack of priming sugar...can't remember the amount but whatever the calculator said for the correct volumes to style. All of these beers were carbed perfectly after a month or so. It was only after the extended storage they cranked up. The beer is still clear and tastes good so I'm not convinced its any kind of infection. My sanitation process is to submerge bottles in star san til full and let them sit while preparing everything else. I completely fill my bucket with star san first to fill the bottles and second after I do so...then I use my racking cane to transfer the star san solution to an empty carboy before racking into the bottling bucket. Caps are submerged in star san until they are crimped on the bottles as well...Any ideas? Each beer was left in primary for 4 weeks @ 65 F and at the correct final gravity at bottling.

Thanks

 

[honeybadger]

I find that after 3-4 weeks carbing, my beers are at the minimum carb level for drinking. Usually I drink them pretty quickly after that... but the ones that do get left around for a few months always have higher carbonation levels then the month old ones.

The 3 weeks quoted for bottle carbonation is the absolute minimum, so it stands to reason that some beers will continue carbing for some time after.

 

[Bsquared]

One thing to consider is that beer out of the fermenter will have some CO2 dissolved in it already, like 1-1.5 volumes. So if you are calculating the amount of sugar needed to go from 0 to you desired carbonation level and not accounting for this volume all ready dissolved in the beer your going to over shoot your desired volumes.

It takes longer to get there though, because as the pressure in the bottle builds the yeast become less active, and at cooler temps it can be even slower. so the beer might not become over carbonated till much later.

 

[DMartin]

Add a little less priming sugar. This will decrease the maximum carb level in the long run, but will increase the minimum wait time in the short term.

Try experimenting with 4.0 oz in a 5 gal batch (vs the usual 5.0) and increase or decrease by the .25 oz based on your results. Ultimately, it's your beer. Your personal tastes and those of your friends and family should dictate the final result.

EDIT: I also agree with the above post. The colder your bottles are, the longer it'll take to carb. On the other hand, if you let em get too much over 70, you've got entirely new issues to deal with