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I've been looking for a soda bread recipe to try and I notice that most of them contain buttermilk. Buttermilk is not a standard part of my pantry. Part of the appeal of soda bread is that it's quick to throw together, so having to go shopping for a specific ingredient interferes with the spontaneous aspect. I know there are lots of substitutions for buttermilk (using a bit of lemon juice in regular milk is the one I usually use), but I'm wondering what it is about buttermilk specifically that seems to be a standard part of soda bread. Is it just traditional? Or will it add a particularly noticeable flavour/texture?Edited to add: I know that its functional purpose is to provide an acid to react with the soda for rising; so is it just that it used to be the most convenient acid?
Why does soda bread call for buttermilk?