Originally Posted by Lost
My bad, apologies for giving out bad advice.
I've never noticed my beers being over carbed but then again I'm not too picky about carb levels either. my non-temp regulated fridge probably has pretty big temp swings which also messes with carb levels.
So why exactly do kegs require less priming sugar? Less headspace? But wouldn't that be highly variable depending on batch size variations? I don't see the mechanism whereby vessel size or shape would affect carb levels. I'm not disagreeing with you, I'm just curious.
All of the books that covered the topic always attributed it to the difference in head space ratios, with the assumption that a five gallon keg would in fact be carbonated with five gallons of brew within, and a standard bottle would have 12 ounces of brew within.
Now, I do have to say that there have been many concepts universally accepted and published as gospel in my fairly extensive brewing book collection that apparently
have since been questioned if not outright refuted (see "yeast autolysis"
) so there is certainly the chance that this could turn out to be yet another case of oft-repeated brewer folklore. But the one "natural carbonation" calculator I tried yesterday definitely followed the "bottle vs keg" paradigm contained in those books.
I don't naturally carbonate my kegs, but if I did I'd consider that eventually the contents are going to be sitting for at least a couple of weeks under serving pressure anyway (12psi here) so I'd likely go with the ~30% less fermentable strategy with the assumption that it would only take a few days under pressure to bring the typical brew up to the ~2.4 volume level.
Dealing with overcarbed kegs is a distraction, I'd rather sneak up to a good level that be fighting back down...