Originally Posted by CaptYesterday
Turbodog would be an example of a beer that tastes completely different when served in bottle as opposed to on tap.
This is a great example. Turbodog on tap is great, fresh at the brewery it is fantastic, but in the bottle it is not as good. I know for a fact that Abita pasteurizes the beer that goes into bottles and does not pasteurize the beer that goes into kegs.
Other than the pasteurize/not pasteurized reason, I think there are a couple other reasons draft tends to be better:
-The beer in the kegs has never seen light (even though brown bottles help this cause a lot).
-It is easier to handle kegs correctly. In my experience (at package stores, etc.) kegs are almost always stored cold, not on shelf under lights at room temperature.
-Kegs are a bigger investment for stores/distributors, they do not order pallets and let them sit around for months (or years) like bottles.
-It is also very possible that breweries have ways of purging kegs of oxygen better than bottles and depending on the headspace in the keg, there is a lot less room for oxygen exposure. Oh, and caps don't always keep all oxygen out.
I think recipe differences between draft and bottle are very much the exception, not the rule. You need to have a much larger capacity and demand (like SN) to be able to do this, it is essentially like having to brew 2 different beers.