Buffering capacity of finished beers?

Does anybody have an idea of the buffering capacity of various beers. This weekend I'm going to do some testing of how various salt additions affect the flavor of finished beers and I thought it might be nice to examine what changes in pH do to the taste as well. If I have a ballpark idea of the buffering capacity, then I could calculate how much acid (phosphoric) and how much base (calcium hydroxide) I need to add before it affects the pH.

I can of course just set up my pH meter and titrate the beer, which is probably what I'll end up doing, but it is always nice to have a ballpark idea of how much titrant will be needed (and also how strong/weak to make up the titrant).

I'll probably test this on a Porter and a CAP. I'm particularly curious to see how salts and pH affect the porter.

I have this: http://braukaiser.com/blog/blog/2010/11/25/wort-and-beer-titration/

I'd just take a pH meter and add base or acid until you have the desired pH. I actually did this a few days ago on a Schwarzbier using Ca(OH)2. I created samples with a pH of 4.4, 4.5, 4.5 and 4.7. They did not taste as different as I expected them to taste.

Kai

Thanks Kai, that gives me a starting point. I did this before in a very unscientific way with some sour beer, and I did notice a change, but then again, I don't know what the final pH was. I'll be more careful this time.